ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Inorganic Chemistry  (8,886)
  • Life and Medical Sciences  (1,555)
  • Aircraft Design, Testing and Performance  (75)
  • Insekten  (20)
  • Humans
  • SPACE SCIENCES
  • 1940-1944  (2,302)
  • 1935-1939  (3,968)
  • 1930-1934  (4,266)
Collection
Keywords
Publisher
Years
Year
  • 1
    facet.materialart.
    Unknown
    In:  Anz. Schädl.kunde 20: 16ff
    Publication Date: 1944
    Description: Beziehung zwischen Klima und Insektenbiologie KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: Deutschland, teilw. einzelne Regionen ; 1936-1941 ; Insekten ; Luftfeuchte ; Forst ; Klima ; Niederschlag ; Pflanzenschädling ; Temperatur
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    facet.materialart.
    Unknown
    In:  Schweiz Ztschr. Forstwes. 93: 330-332
    Publication Date: 1942
    Description: Beschreibung über das außergewöhnliche Massenauftreten der Buchenblattgallmücke im Kanton Glaurus, fast jedes Blatt war befallen, bereits am 1. August war große Zahl der Blätter dürr KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: Schweiz ; 1942 ; Insekten ; Buche ; Pflanzenschädling
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    facet.materialart.
    Unknown
    In:  Ann. ent. fenn. 10: 181-183
    Publication Date: 1944
    Description: Beschreibung des Überwinterungsverhaltens des Kiefernspinners KATASTER-BESCHREIBUNG: Zusammenhang zwischen geografischer Breite, Temperatur und dem Überwinterungsverhalten des Kiefernspinners KATASTER-DETAIL: Delta T-, dann zweimaliges Überwintern der Larven bei Versuchen in Finnland
    Keywords: Finnland ; 1940-44 ; Insekten ; Kiefer ; Pflanzenschädling ; Temperatur
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    facet.materialart.
    Unknown
    In:  Tharandter forst. Jahrb. 93: 681-687
    Publication Date: 1942
    Description: Auswertung der in Sachsen durchgeführten Anlockversuche und des Abfaltens über die Biologie der Nonne KATASTER-BESCHREIBUNG: Verschiebung der Hauptflugzeit des Falters, Unterschiede um bis 10-20 Tage feststellbar KATASTER-DETAIL:
    Keywords: Sachsen ; 1937-1942 ; Insekten ; Forst ; Pflanzenschädling
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    facet.materialart.
    Unknown
    In:  Ztschr. Forst-, Jagdwesen 73: 201-246
    Publication Date: 1941
    Description: Beschreibung des Zusammenhangs zwischen der Eizahl und der Kokonzahl der Kiefernhornblattwespe auf das Massenauftreten KATASTER-BESCHREIBUNG: Betimmung der kritischen Anzhal Eier und der kritischen Anzahl Winter- und Sommerkokons für das Massenauftreten KATASTER-DETAIL:
    Keywords: Sachsen, Brandenburg, Mecklenburg-Vorpommern ; 1939-40 ; Insekten ; Kiefer ; Pflanzenschädling
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    facet.materialart.
    Unknown
    In:  Ztschr. Pfl.krankh. 51: 257-278
    Publication Date: 1941
    Description: Beschreibung der Massenvermehrung der Kiefernblattwespe, Hauptgrung ist die Umwandlung von ursprünglich Laubwaldgesellschaften in reine Kieferngesellschaften, Bedeutung der Temperatur für das Überliegen der Larven KATASTER-BESCHREIBUNG: Temperatur und Luftfeuchte für das Überliegen der Larven entscheidend und damit auch für ein Massenauftreten im darauffolgenden Jahr, Begünstigung der Parasitierung der Kieferblattwespe KATASTER-DETAIL: Delta T- (Juli-August und im Winter), dann Geschlechterfolge von Diprion pini stark dezimiert
    Keywords: Slowakei ; 1939-40 ; Insekten ; Luftfeuchte ; Kiefer ; Pflanzenschädling ; Temperatur ; Parasit
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    facet.materialart.
    Unknown
    In:  Ztschr. angew. Ent. 29: 412-441 u. 601-635
    Publication Date: 1942
    Description: Beschreibung der Biologie der Buschhornblattwespe vom Schlüpfen, über die Entwicklung bis hin zum Überliegen und die abiotischen Sterlichkeitsursachen, u.a. witterungsbedingt KATASTER-BESCHREIBUNG: Beginn der Frühjahrsgeneration ist klima- und wetterbedingt, unter günstigen Bedingungen (milder Winter) bereits im Januar Beginn der Entwicklung und Schlupfbeginn ab Anfang April KATASTER-DETAIL: Tmit- (Spätfrühjahr und Frühwinterwitterung) , dann Schlupfbeginn später und Anteil der Überlieger höher
    Keywords: Mecklenburg-Vorpommern ; 1937-1940 ; Insekten ; Kiefer ; Pflanzenschädling ; Temperatur ; Vegetationsperiode ; Wachstum ; Witterung
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 1941
    Description: Beobachtungen über das vermehrte Auftreten der Kiefernschonungs-Gespinstblattwespe KATASTER-BESCHREIBUNG: Durch Massenvermehrung der Kiefernschonungs-Gespinstblattwespe und Fraß an Nadeln des Maitriebes bei Kieferen kommt es zum Absterben der Bäume, vorwiegend auf Kuppen und sandigen Standorten, weniger in Mulden und Senken KATASTER-DETAIL: Massenauftreten der Kiefernschonungs-Gespinstblattwespe führte bis 1939 zu Absterben von mindestens 5% der Kiefernbestände, nach 1940 noch höhere Schäden
    Keywords: Mecklenburg-Vorpommern ; 1920-40 ; Insekten ; Kiefer ; Pflanzenschädling
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    facet.materialart.
    Unknown
    In:  Mitt. Biol. Reichsanst. H. 63: 46-48
    Publication Date: 1941
    Description: Beschreibungen zum Gesundheitszustand einer Population von Nonnen, ihrer Lebens- und Vermehrungsfähigkeit im Zusammenhang mit dem Massenauftreten, aber auch dem Zusammenbrechen der Population KATASTER-BESCHREIBUNG: Verringerung der Populationssichte durch Räuber kann bei 95% liegen KATASTER-DETAIL:
    Keywords: Deutschland ; 1900-1940 ; Insekten ; Forst ; Pflanzenschädling
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    facet.materialart.
    Unknown
    In:  Dtsch. Forstztg. 10: 307-308
    Publication Date: 1941
    Description: Beschreibung der großen Frassschäden der letzten Jahrzehnte, bezug der Temperatur und des Niederschlages auf die Entwicklungsmöglichkeit einer Population KATASTER-BESCHREIBUNG: Ziiterte Untersuchungen zur Entwicklung der Nonnenraupe KATASTER-DETAIL: Delta T+ (Temperaturoptimum von 21.5°C, Ende April-Anfang Mai), dann günstige Entwiclungsbedingungen Delta Nied- (relative Feuchte schwankt zwischen 50-100%), dann Absterben großer Zahl futtersuchender Raupen
    Keywords: Deutschland, teilw. einzelne Regionen ; 1850-1940 ; Insekten ; Luftfeuchte ; Fichte ; Forst ; Kiefer ; Niederschlag ; Pflanzenschädling ; Temperatur
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    facet.materialart.
    Unknown
    In:  Ann. Ent. fenn. 8: 49-71
    Publication Date: 1942
    Description: Schadinsekten und Pilze der Espe, Beschreibung und Beziehung verschiedener Insekten und Pilze an dem Vertrockungsprozess KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: Finnland ; 1939-1940 ; Insekten ; Forst ; Pflanzenschädling
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    facet.materialart.
    Unknown
    In:  Rev. canad. Biol. 2: 149-167
    Publication Date: 1943
    Description: Studien über die Schlupftermine der Europäischen Fichtenbuschhornblattwespe, Übertragbarkeit von Entwicklungstadien bei gleicher klimatischen Bedingungen KATASTER-BESCHREIBUNG: Durch Einteilung in klimatische Zonen konnte die Unterschiede in Tagen des Ausschlüpfen aus den Eiern der Fichtenbuschhornblattwespe für Kanada und die USA dargestellt werden. KATASTER-DETAIL:
    Keywords: Kanada und USA ; 1940-42 ; Insekten ; Fichte ; Pflanzenschädling ; Temperatur
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Publication Date: 1942
    Description: Beobachtungen zur Massenvermehrung des Kiefernspanners in gleichaltrigem, umgleichaltrigem und Kiefern-Eichenbestand und der Bezug zu abiotischen Faktoren KATASTER-BESCHREIBUNG: Beziehung zwischen Kiefernspanner und belebter Umwelt, im Mischwaldbeständen ist Dynamik höher, Anteil des Wetters an der Mortalität liegt bei ca. 12% (mit sehr starken Schwankungen), stark abhängig von der Lebensbedingungen für die natürlichen Feinde des Spinners KATASTER-DETAIL:
    Keywords: Sachsen-Anhalt ; 1936-1937 ; Insekten ; Kiefer ; Pflanzenschädling
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    facet.materialart.
    Unknown
    In:  Ann. Ent. fenn., Helsinki, 8: 143-163
    Publication Date: 1942
    Description: Vertrockungnung der Eberesche, der Salweide durch den Befall mit Kleinschmetterlingen, bzw. Käfern und sekundär Pilzen, Bescchreibung der Prozesse und Auswirkungen KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: Finnland ; 1939-40 ; Insekten ; Forst ; Pflanzenkrankheit ; Pflanzenschädling
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    facet.materialart.
    Unknown
    In:  Mitt. Forstwirtsch. u. -wissensch. 12: 25-68
    Publication Date: 1941
    Description: Auswertung verschiedener Parameter (Nonnenraupen, Falterflug) in unterschiedlichen Überwachungsbereichen der Forstentomologischen Dienststellen, Befallsermittlungsverfahren nach der Wellensteinschen Methode KATASTER-BESCHREIBUNG: Rhytmische Schwankungen der plötzlichen Übervermehrung, 10 oder 12 jährige Perioden, Bezug zu Schwankungen der Umweltbedingungen KATASTER-DETAIL:
    Keywords: Nord- und Mitteldeutschland ; 1939-40 ; Insekten ; Fichte ; Forst ; Kiefer ; Pflanzenschädling
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Publication Date: 1943
    Description: Untersuchungen über die Wirkung von Schnee, Eis und Kälte auf die Eigelege des Schwammspinners KATASTER-BESCHREIBUNG: Niedrige Temperaturen (Januar-März) von bis zu -11.4°C hatte keine nachhaltige Auswirkungen auf die Vitalität der Eigelege, eher waren mechanische Beschädigungen z.B. durch Abkratzen der Eigelege Ursachen für das Nichtschlüpfen der Tiere KATASTER-DETAIL:
    Keywords: Kroatien, Europa ; 1938-40 ; Insekten ; Eiche ; Pflanzenschädling ; Temperatur ; Frost
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Publication Date: 1942
    Description: Zusammenhang zwischen dem Abgang von Puppen der Kieferneule und abiotischen Faktoren KATASTER-BESCHREIBUNG: Zusammenhang zwischen der Überlebensrate der Puppen der Kieferneule und der Feuchtikeit in einzelnen Monaten, Optimum der relativen Feuchte für die Entwicklung bei 91% Luftfeuchte, günstigste Puppenlager sind trockene Standorte KATASTER-DETAIL: Nied+ (Mittelfeuchte und feuchte Lagen sowie in Mischlagen im Frühjahr), dann höherer Abgang von Puppen
    Keywords: Mecklenburg-Vorpommern ; 1939-1941 ; Insekten ; Luftfeuchte ; Kiefer ; Pflanzenschädling
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    facet.materialart.
    Unknown
    In:  Ztschr. angew. Ent. 28: 357-365
    Publication Date: 1941
    Description: Vertrocknungsprozess der Espe, Beschreibung und Beziehung verschiedener Insekten und Pilze an diesem Prozess KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: Finnland ; 1936-1941 ; Insekten ; Forst ; Pflanzenschädling
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    facet.materialart.
    Unknown
    In:  Anz. Schädl.kunde 20: 13-16
    Publication Date: 1944
    Description: Beschreibung zum Befall von kanadischen Pappeln mit dem Prachtkäfer KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: Rheinland-Pfalz ; 1934-1943 ; Insekten ; Forst ; Pflanzenschädling
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    facet.materialart.
    Unknown
    In:  In U. S. Department of Agriculture, (ed.) A Selected and Annotated Bibliography, Washington.
    Publication Date: 1931
    Description: Kompendium zum Zusammenhang Wetter und Pflanzen, landwirtschaftlich, gärtnerische und forstwirtschaftliche Kulturen, Schädlinge und Gesundheit, 2324 Literaturstellen mit kurzer Zusammenfassung KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: weltweit ; 1650-1930 ; Insekten ; Umweltmedizin ; Zuckerrüben ; Kartoffeln ; Anbautermine ; Infektionskrankheiten ; Boden ; Botanik ; Buche ; Eiche ; Ertrag ; Fichte ; Forst ; Getreide ; Hafer ; Kiefer ; Klima ; Korrelationsmethode ; Landwirtschaft ; Mais ; Niederschlag ; Pflanzenkrankheit ; Pflanzenschädling ; Phänologie ; Rangordnungsmethode ; Roggen ; Roterle ; Temperatur ; Trockenheit ; Vegetationsperiode ; Verdunstung ; Wachstum ; Waldbrand ; Waldwachstum ; Wassermangel ; Weizen ; Wetterbeobachtung ; Wind ; Witterung ; Witterungsextreme ; Düngung ; Globalstrahlung ; Hackfrüchte ; Erbsen ; Wein
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Publication Date: 2013-08-31
    Description: Development work on an arrangement using ailerons and spoilers for lateral control was carried out by the Vought-Sikorsky Aircraft Division of the United Aircraft Corporation on a small commercial airplane in flight and on an airfoil in a wind tunnel. Spoiler hinge moments were reduced by aerodynamic balance. The arrangement was then built into an experimental airplane and further improvements were adopted as the result of flight and tunnel tests. The use of ailerons for lateral control with flaps up, spoilers with flaps full down, and gradual transition as the flaps are lowered was found to provide lateral control under the flight conditions for which they were best suited. The ailerons were of short span, permitting the use of long-span flaps, and were drooped to a relatively large angle when the flaps were deflected. A high maximum lift coefficient was thus attained. With large control deflections in the intermediate flap-angle range and spoiler effectiveness near neutral improved by "ventilating" the spoiler, the lateral control was satisfactory for the experimental airplane and was a definite improvement over that of a conventional control arrangement.
    Keywords: Aircraft Design, Testing and Performance
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Publication Date: 2018-06-05
    Description: An investigation has been conducted on a full-scale model of the proposed XP-46 airplane in the N. A. C. A. full-scale wind tunnel pursuant to the request of the Amy Air Corps, Materiel Division. The primary purpose of the investigation was to determine the optimum arrangement of the various component parts to obtain the maximum high speed and to provide adequate engine cooling. Additional tests included a determination of the stalling characteristics and the effectiveness of ailerons and elevators. The profile drag of the wing was ascertained by the momentum method; the location of the transition point on the wing and the critical compressibility velocities of the various airplane components were determined from surface pressure surveys.
    Keywords: Aircraft Design, Testing and Performance
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Publication Date: 2019-06-28
    Description: Seamless steel tubing is today the principal material of construction for aircraft. The commercial grade of tubing containing about 0.10 to 0.20% carbon at first used is being superseded by two grades which are approved by the army and navy, and which are also becoming standard for commercial airplanes.
    Keywords: Aircraft Design, Testing and Performance
    Type: AD-B204801 , NASA-TM-111285 , NACA-TN-342 , NAS 1.15:111285
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Publication Date: 2018-06-05
    Description: An extensive series of wind-tunnel tests on a half-scale conventional, nacelle model were made by the United Aircraft Corporation to determine and correlate the effects of many variables on cooling air flow and nacelle drag. The primary investigation was concerned with the reaction of these factors to varying conditions ahead of, across, and behind the engine. In the light of this investigation, common misconceptions and factors which are frequently overlooked in the cooling and cowling of radial engines are considered in some detail. Data are presented to support certain design recommendations and conclusions which should lead toward the improvement of present engine installations. Several charts are included to facilitate the estimation of cooling drag, available cooling pressure, and cowl exit area.
    Keywords: Aircraft Design, Testing and Performance
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Publication Date: 2018-06-05
    Description: Experience has shown that the determination of the take-off and. landing characteristics of airplanes requires specialized, equipment of a high degree of precision and reliability and demands great care in the evaluation and interpretation of data. It is believed, therefore, that a description of the apparatus and methods that have been developed by the NACA for these measurements might be of considerable interest, particularly to flight-test groups that have had little experience with landing and. take-off measurements. The basic principles and essential details of the Committee's equipment are described, the methods of utilizing the apparatus and of reducing the data are explained, and sample test results are presented.
    Keywords: Aircraft Design, Testing and Performance
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    Publication Date: 2019-06-28
    Description: A study was made of the performance of a jet-propulsion system composed of an engine-driven blower, a combustion chamber, and a discharge nozzle. A simplified analysis is made of this system for the purpose of showing in concise form the effect of the important design variables and operating conditions on jet thrust, thrust horsepower, and fuel consumption. Curves are presented that permit a rapid evaluation of the performance of this system for a range of operating conditions. The performance for an illustrative case of a power plant of the type under consideration id discussed in detail. It is shown that for a given airplane velocity the jet thrust horsepower depends mainly on the blower power and the amount of fuel burned in the jet; the higher the thrust horsepower is for a given blower power, the higher the fuel consumption per thrust horsepower. Within limits the amount of air pumped has only a secondary effect on the thrust horsepower and efficiency. A lower limit on air flow for a given fuel flow occurs where the combustion-chamber temperature becomes excessive on the basis of the strength of the structure. As the air-flow rate is increased, an upper limit is reached where, for a given blower power, fuel-flow rate, and combustion-chamber size, further increase in air flow causes a decrease in power and efficiency. This decrease in power is caused by excessive velocity through the combustion chamber, attended by an excessive pressure drop caused by momentum changes occurring during combustion.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-WR-E-212 , NACA-ACR-E4E06
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Publication Date: 2019-06-28
    Description: Flights were made in natural icing conditions at the NACA Ice Research Project, Minneapolis, Minn. to test several designs of thermal-electric propeller de-icing blade shoes and a hub-generator design. It was found that a minimum average unit power of 2.5 watts per square inch of blade-shoe area would protect the propeller blades at the test conditions. The most satisfactory blade shoe of the three designs tested extended to the 20-percent-chord point and to 90 percent of the blade radius. A concentration of heat in the leading-edge region of this shoe was found to reduce the power input necessary for satisfactory de-icing. A satisfactory thermal design of blade shoe and a hub generator of sufficient capacity were developed.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-WR-A-47 , NACA-ARR-4A20
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Publication Date: 2019-06-28
    Description: The effects of changes in aileron rigging between 2 deg up and 2 deg down on the stick forces were determined from wind-tunnel data for a finite-span wing model. These effects were investigated for ailerons deflecting equally in both directions and linearly with stick deflection. Data were analyzed for a Frise, a sealed internally balanced, and a beveled-trailing-edge aileron. The results of the analysis showed that only ailerons having linear hinge-moment characteristics are unaffected by changes in rigging and indicated that ailerons having decidedly nonlinear hinge-moment-coefficient curves, particularly for deflections near 0 deg, are very sensitive to changes in rigging.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-WR-L-289 , NACA-RB-L4E11
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Publication Date: 2019-06-28
    Description: Aerodynamic characteristics of a tapered NACA 23012 airfoil with single and double perforated split flaps have been determined in the NACA 7- by 10-foot wind tunnel. Dynamic pressure surveys were made behind the airfoil at the approximate location of the tail in order to determine the extent and location of the wake for several of the flap arrangements. In addition, computations have been made of an application of perforated double split flaps for use as fighter brakes. The results indicated that single or double perforated split flaps may be used to obtain satisfactory dive control without undue buffeting effects and that single or double perforated split flaps may also be used as fighter brakes. The perforated split flaps had approximately the same effects on the aerodynamic and wake characteristics of the tapered airfoil as on a comparable rectangular airfoil.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-WR-L-373
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Publication Date: 2019-06-28
    Description: Cooling tests were made of a Northrop A-17A attack airplane successively equipped with a conventional.NACA cowling and with a wing-duct cooling system. The method of cooling the engine by admitting air from the propeller slipstream into wing ducts, passing it first through the accessory compartment and then over the engine from rear to front, appeared to offer possibilities for improved engine cooling, increased cooling of the accessories, and better fairing of the power-plant installation. The results showed that ground cooling for the wing duct system without cowl flap was better than for the NACA cowling with flap; ground cooling was appreciably improved by installing a cowl flap. Satisfactory temperatures were maintained in both climb and high-speed flight, but, with the use of conventional baffles, a greater quantity of cooling air appeared to be required for the wing duct system.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TN-813
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Publication Date: 2019-06-28
    Description: NACA model 11-C was tested according to the general method with the angle of afterbody keel set at five different angles from 2-1/2 degrees to 9 degrees, but without changing other features of the hull. The results of the tests are expressed in curves of test data and of non-dimensional coefficients. At the depth of step used in the tests, 3.3 percent beam, the smaller angles of afterbody keel give greater load-resistance ratios at the hump speed and smaller at high speed than the larger angles of afterbody keel. Comparisons are made of the load-resistance ratios at several other points in the speed range. The effect of variation of the angle of afterbody keel upon the take-off performance of a hypothetical flying boat of 15,000 pounds gross weight having a hull of model 11-C lines is calculated, and the calculations show that the craft with the largest of the angles of afterbody keel tested, 9 degrees, takes off in the least time and distance.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TN-541
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    Publication Date: 2019-06-28
    Description: A survey of methods and equipment used in the riveting of German aircraft. Includes descriptions and illustrations.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TM-596
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2019-06-28
    Description: This report describes the Bucharest wind tunnel and presents numerous photographs and diagrams. The wind tunnel is of the closed- circuit type, the return being symmetrical with respect t o the longitudinal axis of the tunnel. Th e tunnel is of the horizontal type with a diameter of 3. 2 m (10. 5-ft.) a t the beginning of the entrance cone, and 1.5 m ( 4,92 ft.) at the entrance to the test chamber. The latter, 2 m (6.56 ft.) long, may be either of the open-jet type or enclosed in a cylindrical housing.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TM-651
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    Publication Date: 2019-06-28
    Description: In open box beams subjected to torsion, secondary stresses arise owing to lateral bending of the spar caps. The present paper outlines a simple method for estimating the magnitude of these stresses and gives the results of tests of an open box beam in the neighborhood of a discontinuity where the cover changed from the top to the bottom of the box.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-WR-L-14 , NACA-ARR-L4I23
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    Publication Date: 2019-06-28
    Description: An investigation was carried out in the NACA low-turbulence tunnel to develop low-drag airfoil sections suitable for admitting air at the leading edge. A thickness distribution having the desired type of pressure distribution was found from tests of a flexible model. Other airfoil shapes were derived from this original shape by varying the thickness, the camper, the leading-edge radius, and the size of the leading-edge opening. Data are presented giving the characteristics of the airfoil shapes in the range of lift coefficients for high-speed and cruising flight. Shapes have been developed which show no substantial increases in drag over that of the same position along the chord. Many of these shapes appear to have higher critical compressibility speeds than plain airfoils of the same thickness. Low-drag airfoil sections have been developed with openings in the leading edge as large as 41.5 percent of the maximum thickness. The range of lift coefficients for low drag in several cases is nearly as large as that of the corresponding plain airfoil sections. Preliminary measurements of maximum lift characteristics indicate that nose-opening sections of the type herein considered may not produce any marked effects on the maximum lift coefficient.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-WR-L-694
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    Publication Date: 2019-06-28
    Description: No abstract available
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-WR-L-577 , AD-A801579
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    Publication Date: 2019-06-28
    Description: A correlation of what are believed to be the most reliable data available on duct components of aircraft power-plant installations is presented. The information is given in a convenient form and is offered as an aid in designing duct systems and, subject to certain qualifications, as a guide in estimating their performance. The design and performance data include those for straight ducts; simple bends of square, circular, and elliptical cross sections; compound bends; diverging and converging bends; vaned bends; diffusers; branch ducts; internal inlets; and an angular placement of heat exchangers. Examples are included to illustrate methods of applying these data in analyzing duct systems. (author)
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-WR-L-208 , NACA-ARR-L4F26
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    Publication Date: 2018-06-05
    Description: The available test results of internally balanced ailerons have been correlated and summarized herein. Although several variables have yet to-be-investigated, the results presented will be useful in the preliminary design of internally balanced ailerons and in the determination of the most promising modifications to unsatisfactory ailerons.
    Keywords: Aircraft Design, Testing and Performance
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Publication Date: 2018-06-05
    Description: The Army Air Force has made available several pursuit-type airplanes for quantitative investigation of their flying and handling qualities. One Item of special interest obtained from the results of the investigation is a comparison of the aileron control characteristics of the P-36, P-40, Hawker Hurricane, and Supermarine Spitfire airplanes. Figure 1 shows the design characteristics of the ailerons and the control sticks of the four airplanes. Aileron effectiveness may be expressed in terms of the helix angle generated by the wing tip in a steady roll. This angle is given by the expression pb/2V, where p is the rolling velocity, b the wing span, and V the true airspeed, expressed in consistent units. This quantity is convenient to use because, although it does not rep resent directly the rolling velocity of airplanes of different spans or airplanes operating at different speeds, it provides a satisfactory basis for computing the rate of roll and the time required to bank a given amount under any given set of conditions. The ratio of pb/2V obtained in any roll to the maximum value reached with full aileron deflection indicates the fraction of the maximum aileron travel that was reached. A complete discussion of this criterion for aileron effectiveness is given in reference 1. The aileron effectiveness of the various airplanes is compared in the following table on the basis of the response obtained with stick forces of 30 and 5 pounds. A force of 30 pounds is somewhat less than the greatest stick force exerted by the pilot. Repeated flight measurements have shown, however, that this force is a reasonable upper limit for maneuvering at high speeds.
    Keywords: Aircraft Design, Testing and Performance
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    Publication Date: 2018-06-05
    Description: The present trend is toward faster and larger pursuit airplanes. Because both speed and size increase the aileron control forces, the design of ailerons for manual operation is becoming increasingly difficult. In order to obtain a clearer picture of the future problem of balancing ailerons, and inspection has been made of the effects of airplane size and speed on the control forces. Computations were made of the aileron control forces required to meet specified rolling conditions for plain ailerons on wings with spans from 40 to 80 feet and for speeds up to 500 miles per hour. The rolling conditions were specified by two alternative criterions. One was the rolling criterion pb/2V of reference 1. For reasons, which will be discussed later, a value of 0.09 rather than the recommended value of 0.07 was assigned to this criterion. For the criterion pb/2V, the required value of the rolling velocity p varies inversely with the airplane span b. There is some question as to whether the rolling velocity of a pursuit airplane can be permitted to decrease simply because its size is increased. For the second criterion, therefore, the rolling velocity is independent of span (p/V is a constant). The value assigned to this criterion was so chosen that for a wing of 40-foot span the value of pb/2V would be 0.09. The computations neglected compressibility effects. Available experimental data and the results of tests given in reference 2 indicate that the effect of compressibility is to increase the control force. Recent flight tests have indicated that, with certain types of aileron, serious compressibility effects may cause discontinuity at speeds of approximately 400 miles per hour in the aileron control force curves.
    Keywords: Aircraft Design, Testing and Performance
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    Publication Date: 2019-06-28
    Description: An investigation has been made in the Langley free-flight tunnel to obtain an experimental verification of the theoretical rudder-free stability characteristics of an airplane model equipped with conventional rudders having negative floating tendencies and negligible friction. The model used in the tests was equipped with a conventional single vertical tail having rudder area 40 percent of the vertical tail area. The model was tested both in free flight and mounted on a strut that allowed freedom only in yaw. Tests were made with three different amounts of rudder aerodynamic balance and with various values of mass, moment of inertia, and center-of-gravity location of the rudder. Most of the stability derivatives required for the theoretical calculations were determined from forced and free-oscillation tests of the particular model tested. The theoretical analysis showed that the rudder-free motions of an airplane consist largely of two oscillatory modes - a long-period oscillation somewhat similar to the normal rudder-fixed oscillation and a short-period oscillation introduced only when the rudder is set free. It was found possible in the tests to create lateral instability of the rudder-free short-period mode by large values of rudder mass parameters even though the rudder-fixed condition was highly stable. The results of the tests and calculation indicated that for most present-day airplanes having rudders of negative floating tendency, the rudder-free stability characteristics may be examined by simply considering the dynamic lateral stability using the value of the directional-stability parameter Cn(sub p) for the rudder-free condition in the conventional controls-fixed lateral-stability equations. For very large airplanes having relatively high values of the rudder mass parameters with respect to the rudder aerodynamic parameters, however, analysis of the rudder-free stability should be made with the complete equations of motion. Good agreement between calculated and measured rudder-free stability characteristics was obtained by use of the general rudder-free stability theory, in which four degrees of lateral freedom are considered. When this assumption is made that the rolling motions alone or the lateral and rolling motions may be neglected in the calculations of rudder-free stability, it is possible to predict satisfactorily the characteristics of the long-period (Dutch roll type) rudder-free oscillation for airplanes only when the effective-dihedral angle is small. With these simplifying assumptions, however, satisfactory prediction of the short-period oscillation may be obtained for any dihedral. Further simplification of the theory based on the assumption that the rudder moment of inertia might be disregarded was found to be invalid because this assumption made it impossible to calculate the characteristics of the short-period oscillations.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-WR-L-184 , NACA-ARR-L4J05A
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    Publication Date: 2019-06-28
    Description: Two graphical methods are presented for determining the stick-free neutral point, and they are extensions of the methods commonly used to determine the stick-free neutral point. A mathematical formula for computing the stick-free neutral point is also given. These methods may be applied to determine approximately the increase in tail size necessary to shift the neutral point (stick fixed or free) to any desired location on an airplane having inadequate longitudinal stability.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-WR-L-251 , NACA-RB-4B21
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Publication Date: 2019-06-28
    Description: No abstract available
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-MR-A4L14
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    Publication Date: 2019-07-13
    Description: The extent of agreement of the theoretical impact computations with the actual phenomenon has not as yet been fully clarified. There is on the one hand a certain imperfection in the theory (simplifying assumptions made) and on the other an insufficiency in the experimental data available. The object of our present paper is to show how far test results agree with the available approximate computation methods, to investigate in greater detail the physical nature of impact on water, and to perfect the experimental method of studying the phenomenon.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TM-1046 , ; 438
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2019-07-12
    Description: Investigations with a view to increasing the lift coefficient of a wing, without greatly increasing the C(sub x min), are chiefly related to the important question of the maximum speed range.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA Misc. Paper No. 37
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    Publication Date: 2019-07-12
    Description: The effect of several armament installations on the drag of a 1/8 scale model of the B-32 airplane was determined. Turrets in the following positions were tested: nose, tail, upper forward, upper aft, and lower. The nose and tail turrets were each equipped with two.50-caliber guns. Upper turrets were of three types: two.50-caliber guns, four.50-caliber guns, and 20-millimeter cannon. Lower turrets were of two types: two.50-caliber guns and four.50-caliber guns. The effect of streamlining the upper two- and four-gun turrets and of extending the lower two-gun turret was determined. The tests were conducted in the Langley 19-foot. pressure tunnel at a Reynolds number of approximately 2,960,000 and a Mach number of 0.13. Large increases in drag coefficient were caused by the complete armament installations. At a lift coefficient of 0. 4 the installations with nonstreamlined upper turrets and the lower turret retracted increased the drag coefficient by 0.0022 and 0.0027 for the two-gun and four-gun turret installations, respectively. Streamlining the upper turrets reduced the drag of these installations by approximately 40 percent with the upper turrets streamlined, the drag increase was about the same for either the two- or four-gun turret installation. The streamlined two-cannon upper turrets increased the drag about the same amount as the two-gun upper turrets that were not streamlined. Extension of the lower turret. increased the drag slightly more than the whole streamlined gun-turret installation.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-MR-L4L30a
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Publication Date: 2019-07-12
    Description: At the request of the Materiel Division, Wright Field, the National Advisory Committee for Aeronautics is conducting a program of flight tests on a Kellett YG-1B autogiro equipped with a new type of rotor blade. The new blades are tapered in both plan form. and thickness and are designed to avoid periodic blade twist. One phase of the investigation, involving determination of the moments of the resultant rotor force about the trunnions on which the hub is pivoted for control, has been completed. The results obtained are reported herein.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-MR-X-1939
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    Publication Date: 2019-07-11
    Description: For computing the critical flutter velocity of a wing among the data required are the position of the line of centers of gravity of the wing sections along the span and the mass moments and radii of inertia of any section of the wing about the axis passing through the center of gravity of the section. A sufficiently detailed computation of these magnitudes even if the weights of all the wing elements are known, requires a great deal of time expenditure. Thus a rapid competent worker would require from 70 to 100 hours for the preceding computations for one wing only, while hundreds of hours would be required if all the weights were included. With the aid of the formulas derived in the present paper, the preceding work can be performed with a degree of accuracy sufficient for practical purposes in from one to two hours, the only required data being the geometric dimensions of the outer wing (tapered part), the position of its longerons, the total weight of the outer wing, and the approximate weight of the longerons, The entire material presented in this paper is applicable mainly to wings of longeron construction of the CAHI type and investigations are therefore being conducted by CAHI for the derivation of formulas for the determination of the preceding data for wings of other types.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TM-1052 , Report of the Central Aero-Hydrodynamical Institute, Moscow; Rept-452
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2019-07-11
    Description: The few available test data on the heat dissipation of wholly or partly heated airfoil models are compared with the corresponding data for the flat plate as obtained by an extension of Prandtl's momentum theory, with differentiation between laminar and turbulent boundary layer and transitional region between both, the extent and appearance of which depend upon certain critical factors. The satisfactory agreement obtained justifies far-reaching conclusions in respect to other profile forms and arrangements of heated surface areas. The temperature relationship of the material quantities in its effect on the heat dissipation is discussed as far as is possible at tk.e present state of research, and it is shown that the profile drag of heated wing surfaces can increase or decrease with the temperature increase depending upon the momentarily existent structure of the boundary layer.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TM-1044 , Jahrbuch 1938 der Deutschen Luftfahrtforschung; 245-256
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2019-08-17
    Description: The writer sets out to prove by calculation and experiment that by extensive utilization of the skin to carry axial load (reduction of stringer spacing) the stringer sections can be made small enough to afford a substantial saving in structural weight. This saving ranges from 5 to about 40 percent.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TM-1031 , Luftfahrtforschung; 18; 9; 331-337
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    Publication Date: 2019-08-13
    Description: An experimental investigation concerned primarily with the extension of test data on the drag of revolving disks, cylinders, and streamline rods to high Mach numbers and Reynolds numbers is presented.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TR-793
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Publication Date: 2019-08-13
    Description: This note discusses the limitations of the conventional tank test of a seaplane model. The advantages of a complete test, giving the characteristics of the model at all speeds, loads, and trim angles in the useful range are pointed out. The data on N.A.C.A. Model No.11, obtained from a complete test, are presented and discussed. The results are analyzed to determine the best trim angle for each speed and load. The data for the best angles are reduced to non-dimensional form for ease of comparison and application. A practical problem using the characteristics of model no.11 is presented to show the method of calculating the take-off time and run of a seaplane from these data.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TN-464
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    Publication Date: 2019-08-13
    Description: The interpretation of the take-off resistance of seaplane floats by model test involves a problem in mechanics, the solution of which forms the basis of this report. The comparison of three float forms is confined to an angle = 5 degree trim run in order to preserve the clearness of the arrangement. But for complete comparison the corresponding curves for several trim runs should be included.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TM-621 , Zeitschrift fur Flugtechnik und Motorluftschiffahrt; 22; 8-12; 1
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2019-08-15
    Description: Unduly high diving speeds can be effectively controlled by diving brakes but their employment involves at the same time a number of disagreeable features: namely, rotation of zero lift direction, variation of diviving moment, and, the creation of a potent dead air region.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TM-1033
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    Publication Date: 2019-11-26
    Description: No abstract available
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-ACR-3I30 , NACA-WR-W-6
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2019-08-13
    Description: Preliminary information on the complex subject of the fatigue strength of fabricated structural members for aircraft is presented in the test results obtained on several different types of airship girders subjected to axial tension and compression in a resonance fatigue machine. A description of this machine as well as numerous photographs of the fatigue failures are given. There is also presented an extended bibliography on the subject of fatigue strength.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TN-637
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2019-07-11
    Description: The report presents a method for the computation of axial fan characteristics. The method is based on the assumption that the law of constancy of the circulation along the blade holds, approximately, for all fan conditions for which the blade elements operate at normal angles of attack (up to the stalling angles). Pressure head coefficient K(sub a) and power coefficient K(sub u) for the force components in the axial and tangential directions, respectively, and analogous to the lift and drag coefficients C(sub y) and C(sub x) are conveniently introduced.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TM-1042 , Report of the Central Aero-Hydrodynamical Institute, Moscow; Rept-295
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    Publication Date: 2019-07-11
    Description: The present paper is devoted to the theoretical and experimental investigation of one of the stationary elements of a fan, namely, the vaneless diffuser. The method of computation is based on the principles developed by Pfleiderer (Forschungsarbeiten No. 295). The practical interest of this investigation arises from the fact that the design of the fan guide elements - vaneless diffusers, guide vanes, spiral casing - is far behind the design of the impeller as regards accuracy and. reliability. The computations conducted by the method here presented have shown sufficiently good agreement with the experimental data and indicate the limits within which the values of the coefficient of friction lie.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TM-1038 , Report of the Central Aero-Hydrodynamical Institute, Moscow; Rept-224
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2019-07-11
    Description: An approximate theory of buffeting is here presented, based on the assumption of harmonic disturbing forces. Two cases of buffeting are considered: namely, for a tail angle of attack greater and less than the stalling angle, respectively. On the basis of the tests conducted and the results of foreign investigators, a general analysis is given of the nature of the forced vibrations the possible load limits on the tail, and the methods of elimination of buffeting.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TM-1041 , Report of the Central Aero-Hydrodynamical Institute, Moscow; Rept-395
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    Publication Date: 2019-07-12
    Description: The drag of several types of gunner's turrets, windshields, blisters, and other protuberances, including projecting guns, was investigated at speeds from 75 to 440 miles per hour in the NACA 8-foot high-speed wind tunnel. The various gunner's enclosures were represented by 1/10 and 1/7 full-size models on a midwing-fuselage combination representative of bomber types. Most of the usual types of retractable turrets are very poor aerodynamically; they caused wind drag increments, dependent upon the size of the turret relative to the fuselage and upon the speed, up to twice the drag of the fuselage alone. A large streamline blister sufficient to enclose completely one type of rotating cylindrical turret caused a drag increment of approximately one-half that of the turret and at the same time provided space adequate for two gunners rather than for one gunner. A large portion of the drag increments for some types of turret appeared to be due to adverse effects on the fuselage flow caused by the turret rather than by the direct drag of the turret.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-202
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Publication Date: 2019-07-12
    Description: A method that utilizes the Doppler effect on radio signals for determining the speed of an airplane and the distance traveled by the airplane has been developed and found to operate satisfactorily. In this method, called the NACA radio ground-speed system, standard readily available radio equipment is used almost exclusively and extreme frequency stability of the transmitters is not necessary. No complicated equipment need be carried in the airplane, as the standard radio transmitter is usually adequate. Actual flight tests were made in which the method was used and the results were consistent with calibrated air speed indications and stop-watch measurements. Inasmuch as the fundamental accuracy of the radio method is far better than either of the checking systems used, no check was made on the limitations of the accuracy.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-ACR-256 , NACA-SR-256
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    Publication Date: 2019-07-12
    Description: Wing ducts for liquid-cooled engine radiators have been investigated in the N.A.C.A. full-scale wind tunnel on a large model airplane. Th e tests were made to determine the relative merits of several types of duct and radiator installations for an airplane of a particular des ign. In the test program the principal duct dimensions were system atically varied, and the results are therefore somewhat applicable to the general problems of wing duct design, although they should be co nsidered as preliminary and only indicative of the inherent possibil ities.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-88
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Publication Date: 2019-07-12
    Description: The relative efficiencies of various engine-propeller combinations were the subject of a study that covered the important flight conditions, particularly the take-off. Design charts that graphically correlate the various propeller parameters were prepared to facilitate the solution of problems and also to c1arify the conception of the relationships of the various engine-propeller design factors. It is shown that, among the many methods for improving the take-off thrust, the use of high-pitch, large-diameter controllable propellers turning at low rotational speeds is probably the most generally promising. With such a combination the take-off thrust may be further increased, at the expense of a small loss in cruising efficiency, by compromise designs wherein the pitch setting is slightly reduced and the diameter is further increased. The degree of compromise necessary to accomplish the maximum possible take-off improvement depends on such design factors as overspeeding and overboosting at take-off as well as depending on the design altitude. Both overspeeding and designing for altitude operation have the same effect on the take-off thrust as compromising in that the propulsive efficiency is increased thereby; boosting the engine, however, has the reverse effect on the propulsive efficiency, although the brake horsepower is increased.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-55
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    Publication Date: 2019-07-12
    Description: Wind-tunnel tests were conducted on a model wing-nacelle combination to determine the practicability of cooling radial engines by forcing the cooling air into wing-duct entrances located in the propeller slipstream, passing the air through the engine baffles from rear to front, and ejecting the air through an annular slot near the front of the nacelle. The tests, which were of a preliminary nature, were made on a 5-foot-chord wing and a 20-inch-diameter nacelle. A 3-blade, 4-foot-diameter propeller was used. The tests indicated that this method of cooling and cowling radial engines is entirely practicable providing the wing of the prospective airplane is sufficiently thick to accommodate efficient entrance ducts , The drag of the cowlings tested was definitely less than for the conventional N.A.C.A. cowling, and the pressure available at low air speed corresponding to operation on the ground and at low flying speeds was apparently sufficient for cooling most present-day radial engines.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-101
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    Publication Date: 2019-07-12
    Description: This report covers a study of the generally available data on load distribution on slots and flaps. The study was made by the National Advisory Committee for Aeronautics at the request of the Material Division, Army Air Corps to furnish information applicable to design criteria for slots and flaps of various types. The data are presented in three main sections: slots (Handley page type), auxiliary airfoils (fixed), and flaps.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-19
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Publication Date: 2019-07-12
    Description: Adjustable cowling flaps, an adjustable-length cowling skirt, and a bottom opening with adjustable flap were tested as means of controlling the rate of cooling-air flow through an air-cooled radial-engine cowling. The devices were tested in the NACA 20-foot tunnel on a model wing-nacelle-propeller combination, through an airspeed range of 20 to 80 miles per hour, and with the propeller blade angle set 23 degrees at 0.75 of the tip radius. The resistance of the engine to air flow through the cowling was simulated by a perforated plate. The results indicated that the adjustable cowling flap and the bottom opening with adjustable flap were about equally effective on the basis of pressure drop obtainable and that both were more effective means of increasing the pressure drop through the cowling than the adjustable-length skirt. At conditions of equal cooling-air flow, the net efficiency obtained with the adjustable cowling flaps and the adjustable-length cowling skirt was about 1% greater than the net efficiency obtained with the bottom opening with adjustable flap.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-144
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Publication Date: 2019-07-12
    Description: One disadvantage that has been apparent in the operation of split flaps as used to date is the time and effort required to operate them. In this communication an investigation is being made of possible means for balancing them aerodynamically to make their operation easier. Several arrangements have been tested in the 7 by 210 foot wind tunnel, and the results of the wind-tunnel tests as well as preliminary flight tests on one of the more promising forms are given in this paper.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-23
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Publication Date: 2019-07-12
    Description: It is shown that on the basis of existing high-speed airfoil data, propeller efficiencies appreciably in excess of 40% do not appear possible at speeds above 500 miles per hour at 20,000 feet. The assumption that present propeller-blade thicknesses cannot be reduced radically, is implied. Until the reliability and applicability of the airfoil data are established, this conclusion must not be regarded as infallible. Dive tests with airplanes equipped with thrust meters and torque meters are proposed to provide an urgently needed check. The design of high-speed propellers is dictated wholly by compressibility considerations. The blade width, thickness, and pitch distribution; also the airfoil sections, the lift coefficient, the propeller diameter, and rpm must all be adjusted if reasonable efficiencies are to be maintained at airplane speeds that are now being approached. Research is urgently needed on: 1) airfoils at subsonic, sonic, and supersonic speeds; 2) propellers at high forward speeds in wind tunnels; 3)propellers in free flight at high speeds; and 4) jet propulsion and related devices. The breakdown of propeller efficiency indicated by airfoil data, should serve as an incentive for accelerated research on jet propulsion. This device may extend the attainable speed of current airplanes to the neighborhood of 550 miles per hour at 20,000 feet.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-187
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Publication Date: 2019-07-12
    Description: An investigation was made in the NACA 5-foot vertical wind tunnel of a large variety of duct inlets and outlets to obtain information relative to their design for the cooling or the ventilation systems on aircraft. Most of the tests were of openings in a flat plate but, in order to determine the best locations and the effects of interference, a few tests were made of openings in an airfoil. The best inlet location for a system not including a blower was found to be at the forward stagnation point; for one including a blower, the best location was found to be in the region of lowest total head, probably in the boundary layer near the trailing edge. Design recommendations are given, and it is shown that correct design demands a knowledge of the external flow and of the internal requirements in addition to that obtained from the results of the wind tunnel tests.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-95
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    Publication Date: 2019-07-12
    Description: The systematic investigation of wing cooling ducts at the NACA laboratory has been continued with tests in the full-scale wind tunnel on ducts of finite span. These results extend the previous investigation on section characteristics of ducts to higher Reynolds numbers and indicate the losses due to the duct ends. The data include comparisons between ducts completely within the ring and the conventional underslung ducts. Methods of flow regulation were studied and data were obtained for a wide range of internal duct resistance. The results show satisfactory correlation between the finite span and the previously measured section characteristics obtained with full-span ducts. The effects of the various design parameters on the duct characteristics are discussed. The cooling power required for the internal duct installation is shown to be only a small percentage of the engine power.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-94
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    Publication Date: 2019-07-12
    Description: The effects of the geometrical arrangement of tricycle landing gears on various characteristics of an airplane equipped with such landing gear is discussed. The characteristics discussed include directional stability, overturning tendencies, steering and ground handling, shimmy, takeoff, and porpoising. The conclusions are summarized in a table.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-63
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Publication Date: 2019-07-12
    Description: A chart is presented for the values of the coefficient in the formula for the critical compressive stress at which buckling may be expected to occur in flat rectangular plates supported along all edges and, in addition, elastically restrained against rotation along the unloaded edges. The mathematical derivations of the formulas required in the construction of the chart are given.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-189
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2019-07-12
    Description: An electrical-type meter has been developed for measuring mass rates of flow of gasoline or other nonconducting fluids. Its temperature dependence is small over a large range and it has no known vibrational or viscosity errors. The maximum temperature rise is less than 5 C. The rates of flow, measurable within 1% with the present instrument, are approximately 100 to 1,000 or more pounds of gasoline per hour when a potentiometer is used, or 100 to 300 pounds per hour when a deflection-type meter is used.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-12
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    Publication Date: 2019-07-12
    Description: Present designs for large flying boats are characterized by high wing loading, high aspect ratio, and low parasite drag. The high wing loading results in the universal use of flaps for reducing the takeoff and landing speeds. These factors have an effect on takeoff performance and influence to a certain extent the design of the hull. An investigation was made of the influence of various factors and design parameters on the takeoff performance of a hypothetical large flying boat by means of takeoff calculations. The parameters varied in the calculations were size of hull (load coefficient), wing setting, trim, deflection of flap, wing loading, aspect ratio, and parasite drag. The takeoff times and distances were calculated to the stalling speeds and the performance above these speeds was studied separately to determine piloting technique for optimum takeoff. The advantage of quick deflection of the flap at high water speeds is shown.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-119
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2019-07-12
    Description: The fundamental principles of fluid flow, pressure losses, and heat transfer have been presented and analyzed for the case of a smooth tube with fully developed turbulent flow. These equations apply to tubes with large length-diameter ratios where the f1ow is at a high Reynolds Number. The error introduced by using these equations increases as the magnitude of the tube length and the air-flow Reynolds Number approaches the values encountered in modern radiator designs. Accordingly, heat-transfer tests on radiator sections were made and the results are presented in nondimensional form to facilitate their use and for comparison with other heat-transfer data. In addition, pressure losses were measured along smooth tubes of circular, square, and rectangular cross section and the results were also correlated and are presented in nondimensional form. The problem of a radiator design for a particular installation is solved, the experimental heat-transfer and pressure-loss data being used, on a basis of power chargeable to the radiator for form drag, for propelling the weight, and for forcing the air through the radiator. The case of an installation within a wing or an engine nacelle is considered. An illustration of radiator design is carried through for an arbitrary set of conditions. Sufficient detail is given to enable the reader to reproduce the analysis for any given case.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-112
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    Publication Date: 2019-07-12
    Description: The drag of closed-cockpit and transport-type windshields was determined from tests made at speeds from 200 to 440 miles per hour in the NACA 8-foot high-speed wind tunnel. This speed range corresponds to a test Reynolds number range of 2,510,000 to 4,830,000 based on the mean aerodynamic chord of the full-span model (17.29 inches). The shapes of the windshield proper, the hood, and the tail fairing were systematically varied to include common types and a refined design. Transport types varied from a reproduction of a current type to a completely faired windshield. The results show that the drag of windshields of the same frontal area, on airplanes of small to medium size, may account for 15% of the airplane drag or may be reduced to 1%. Optimum values are given for windshield and tail-fairing lengths; the effect, at various radii is shown. The longitudinal profile of a windshield is shown to be most important and the transverse profile, to be much less important. The effects of retaining strips, of steps for telescoping hoods, and of recessed windows are determined. The results show that the drag of transport-type windshields may account for 21% of the fuselage drag or may be reduced to 2%.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-114
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    Publication Date: 2019-07-12
    Description: A preliminary investigation of a number of duct entrances of rectangular shape installed in the leading edge of a wing was conducted in the NACA 20-foot tunnel to determine the external drag, the available pressure, the critical Mach numbers, and the effect on the maximum lift. The results showed that the most satisfactory entrances, which had practically no effect on the wing characteristics, had their lips approximately in the vertical plane of the leading edge of the wing. This requirement necessitated extending the lips outside the wing contour for all except the small entrances. Full dynamic pressure was found to be available over a fairly wide range of angle of attack. The critical Mach number for a small entrance was calculated to be as high as that for the plain wing but was slightly lower for the larger entrances tested.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-154
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    Publication Date: 2019-07-12
    Description: Test of 10-foot diameter, 4- and 6-blade single- and dual-rotating propellers were conducted in the 20-foot propeller-research tunnel. The propellers were mounted at the front end of a streamline body incorporating spinners to house the hub portions. The effect of a symmetrical wing mounted in the slipstream was investigated. The blade angles investigated ranged from 20 degrees to 65 degrees; the latter setting corresponds to airplane speeds of over 500 miles per hour. The results indicate that dual-rotating propellers were from 0 to 6% more efficient than single-rotating ones; but when operating in the presence of a wing the gain was reduced about one-half. Other advantages of dual-rotating propellers were found to include greater power absorption and greater efficiency at the low V/nD operating range of high pitch propellers.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-157
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    Publication Date: 2019-07-12
    Description: Since the recent more or less extensive adoption of high-lift flaps on airplane wings, the problem of providing satisfactory lateral control without sacrificing a part of the span of the flaps has become one of some importance. The difficulties have been largely a matter of obtaining satisfactory rolling moments with a smoothly graduated action, together with sufficiently small control forces throughout the entire speed range. As part of an investigation including several different lateral-control arrangements to be used with split flaps, the tests reported in this paper were made on one arrangement in which conventional ailerons of narrow chord are used, and a split flap is retracted into the under surface of th wing forward of th ailerons. When the flap is retracted, the arrangement is as sketched in figure 1(a). If a simple form of split flap were used, hinged at its forward edge, the appearance when deflected would be as shown in figure 1(b). The flap if deflected with its leading edge remaining in this forward position would give somewhat less than three fourths of the lift increase of the same flap in the usual rear position. (See reference 1.). If, as shown in figure 1(c), the split flap ahead of th aileron is moved to the rear as the trailing=edge portion is deflected downward, a double advantage is obtained. The deflected flap can be located in the most effective region for high lift (reference 1), and the force required to deflect the flap is reduced. This is the arrangement used in the present tests.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-14
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    Publication Date: 2019-07-12
    Description: When an airplane is operating at high altitude, it is necessary to use a supercharger to maintain ground pressure at the carburetor inlet. This maintenance and high intake-manifold pressure tends to keep the power output of the engine at ground-level value. The air, being compressed by the supercharger, however, is heated by adiabatic compression and friction to a temperature that seriously affect the performance of the engine. It is thus necessary to use an intercooler to reduce the temperature of the air between the supercharger outlet and the carburetor inlet. The amount of cooling required of the intercooler depend on the efficiency of the supercharger installation. In this investigation, several types of intercoolers were compared and a design procedure that will give the best intercooler for a given set of conditions is indicated. The figure of merit used for the selection of the best design was the total power consumed by the intercooler. This value includes the power required to transport the weight of the intercooler as well as the power used to force the charge air and the cooling air through the intercooler. The cost, size and practicality of construction were not considered, inasmuch as it was thought that a survey of possibilities of improvement in design would be of interest, regardless of whether the improvement could be immediately realized. Three types of intercoolers are included in this survey: a counterflow intercooler with indirect cooling surface in the form of fins, a counterflow intercooler with direct cooling surfaces, and a cross-flow, tube-type intercooler.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-124
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    Publication Date: 2019-07-12
    Description: An investigation was undertaken to determine the character and importance of the transition phase between the ground run and steady climb in the takeoff of an airplane and the effects of various factors on this phase and on the airborne part of the takeoff as a whole. The information was obtained from a series of step-by-step integrations, which defined the motion of the airplane during the transition and which were based on data derived from actual takeoff tests of a Verville AT airplane. Both normal and zoom takeoffs under several loading and takeoff speed conditions were considered. The effects of a moderate wind with a corresponding wind gradient and the effect of proximity of the ground were also investigated. The results show that, for normal takeoffs, the best transition was realized at the lowest possible takeoff speed. Moreover, this speed gave the shortest overall takeoff distance for normal takeoffs. Zoom takeoffs required a shorter overall takeoff run than normal takeoffs, particularly with a heavy landing, if the obstacle to be cleared was sufficiently high (greater than 50 feet); no advantage was indicated to the airplane with a light loading if the height to be cleared was less. The error resulting from the neglect of the transition in the calculation of the airborne distance of takeoff was found to vary from 4% with the heaviest loading considered to -4% with the lightest loading for normal takeoffs over a 100-ft obstacle; the percentage error was twice as great for a 50-foot obstacle. For zoom takeoffs the error attained much greater values. The average wind gradient corresponding to a 5-mile-per-hour surface wind reduced the airborne distance required to clear a 50-foot obstacle by about 9% with the lightest loading and 16% with the heaviest loading; for both cases. The overall reduction due to this wind was approximately twice that resulting from the wind gradient alone. A simple expression for the reduction of observed takeoff performance to no-wind conditions is presented. Ground effect is shown to reduce the airborne distance to attain a height of 50 foot by 10% with the lightest loading and 16% with the heaviest loading; for a 100-foot obstacle the percentage reduction was about 1/2 as great.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-70
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    Publication Date: 2019-07-12
    Description: An investigation was made in the NACA 7- by 10-foot wind tunnel of a large-chord wing model with a duct to house a simulated radiator suitable for a liquid-cooled engine. The duct was expanded to reduce the radiator losses, and the installation of the duct and radiator was made entirely within the wing to reduce form and interference drag. The tests were made using a two-dimensional flow set-up with a full-span duct and radiator. Section aerodynamic characteristics of the basic airfoil are given and also curves showing the characteristics of the various duct-radiator combinations. An expression for efficiency, the primary criterion of merit of any duct, and the effect of the several design parameters of the duct-radiator arrangement are discussed. The problem of throttling is considered and a discussion of the power required for cooling is included. It was found that radiators could be mounted in the wing and efficiently pass enough air for cooling with duct outlets located at any point from 0.25c to 0.70c from the wing leading edge on the upper surface. The duct-inlet position was found to be critical and, for maximum efficiency, had to be at the stagnation point of the airfoil and to change with flight attitude. The flow could be efficiently throttled only by a simultaneous variation of duct inlet and outlet sizes and of inlet position. It was desirable to round both inlet and outlet lips. With certain arrangements of duct, the power required for cooling at high speed was a very low percentage of the engine power.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-93
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    Publication Date: 2019-07-12
    Description: The torsional deflection of the blades of three full-scale duralumin propellers operating under various loading conditions was measured by a light-beam method. Angular bending deflections were also obtained as an incidental part of the study. The deflection measurements showed that the usual present-day type of propeller blades twisted but a negligible amount under ordinary flight conditions. A maximum deflection of about 1/10th of a degree was found at V/nD of 0.3 and a smaller deflection at higher values of V/nD for the station at 0.70 radius. These deflections are much smaller than would be expected from earlier tests, but the light-beam method is considered to be much more accurate than the direct-reading transit method used in the previous tests.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-84
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    Publication Date: 2019-07-12
    Description: A 1/3.5 full-size model of the Mark V float of the Bureau of Aeronautics, Navy Department, was tested in the NACA tank both with smooth painted bottom surfaces and with roundhead rivets, plate laps, and keel plates fitted to simulate the actual bottom of a metal float. The augmentation in water resistance due to the added roughness was found to be from 10-12% at the hum speed and from 12-14% at high speeds. The effect of the roughness of the afterbody was found to be negligible except at high trims. The model data were extrapolated to full size by the usual method which assumes the forces to vary according to Froude's law, and in the case of the smooth model by a method of separation that takes into account the effect of scale on the frictional resistance. It was concluded that the effect of rivet heads on the takeoff performance of a relatively high-powered float seaplane is of little consequence but that it may be of greater importance in the case of more moderately powered flying boats.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-51
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    Publication Date: 2019-07-12
    Description: In many installations of castering rubber-tired wheels there is a tendency for the wheel to oscillate violently about the spindle axis. This phenomenon, popularly called 'shimmy,' has occurred in some airplane tail wheels and has been corrected in two ways: first by the application of friction in the spindles of the tail wheels; and, second, by locking the wheels while taxiing at high speeds. Shimmy is common with the large wheels used as nose wheels in tricycle landing gears and, since it is impossible to lock the wheels, friction in the nose-wheel spindle has been the sole means of correction. Because the nose wheel is larger than the conventional tail wheel and usually carries a greater load, the larger amounts of spindle friction necessary to prevent shimmy are objectionable. the present paper presents a theoretical and experimental study of the problem of the stability of castering wheels for airplane landing gears. On the basis of simplified assumptions induced from experimental observations, a theoretical study has been made of the shimmy of castering wheels. The theory is based on the discovery of a phenomenon called 'kinematic shimmy' and is compared quantitatively with the results of model experiments. Experimental checks, using a model having low-pressure tires, are reported and the applicability of the results to full scale is discussed. Theoretical methods of estimating the spindle viscous damping and spindle solid friction necessary to avoid shimmy - lateral freedom - is introduced.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-67
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    Publication Date: 2019-07-12
    Description: A chart is presented for the values of the coefficient in the formula for the critical compressive stress at which buckling may be expected to occur in outstanding flanges. These flanges are flat rectangular plates supported along the Loaded edges, supported and elastically restrained along one unloaded edge, and free along the other unloaded edge. The mathematical derivations of the formulas required for the construction of the chart are given.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-188
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    Publication Date: 2019-07-12
    Description: This report describes and gives the results of tests made to determine the effect of lateral inclination of the propeller thrust axis to the direction of flight. A wing-nacelle-propeller combination with the nacelle axis located successively parallel to and at 15 degrees to the perpendicular to the leading edge of a wing was tested with the combination at several angles of yaw. Tests of the wing alone at the same angles of yaw were also made. The data are presented in the usual graphic form. An increase in propulsive efficiency with increase in angle of the thrust axis was found. The change in net efficiency, found by charging the whole nacelle drag to the power unit, was negligible, however, within the range of the tests.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-28
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    Publication Date: 2019-07-11
    Description: Detail calculations are presented of the shifts in stick-fixed neutral point of the Republic XF-12 airplane due to the windmilling propellers and to the fuselage. The results of these calculations differ somewhat from those previously made for this airplane by Republic Aviation Corporation personnel under the direction of Langley flight division personnel. Due to these differences the neutral point for the airplane is predicted to be 37.8 percent mean aerodynamic chord, instead of 40.8 percent mean aerodynamic chord as previously reported.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-CMR-L4J16
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    Publication Date: 2019-08-15
    Description: Pressure distribution and spray measurements were carried out on rectangular flat and V-bottom planing surfaces. Lift, resistance, and center of pressure data are analyzed and it is shown how these values may be computed for the pure planing procees of a flat or V-bottom suface of arbitrary beam, load and speed, the method being illustrated with the aid of an example.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-TM-1061 , Jahrbuch 1937 der Deutschen Luftfahrtforschung; 320-339
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Publication Date: 2019-08-26
    Description: An investigation has been made of the effect of aerodynamic heating on propeller-blade temperatures. The blade temperature rise resulting from aerodynamic heating was measured and the relation between the resulting blade temperatures and the outer limit of the iced-over region was examined. It was found that the outermost station at which ice formed on a propeller blade was determined by the blade temperature rise resulting from the aerodynamic heating at that point.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-153
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    facet.materialart.
    Unknown
    In:  CASI
    Publication Date: 2019-08-26
    Description: With some airplanes the approach to the stall is accompanied by changes in the behavior, such as tail buffeting or changes in the control characteristics of the airplane so that the pilot obtains a warning of the impending stall. Vith other airplanes it is possible to approach the stall without any perceptible warning other than the reading of the air-speed meter, in which case the danger of inadvertent stalling is considerably greater. Although it is not within the scope of this paper to discuss stalling characteristics, it is desired to point out that in general the danger of inadvertent stalling is greatest with those airplanes that behave worse when the stalling occurs; that is, with airplanes in which the stall starts at the wing tips. A warning of the impending stall is desirable in any case, but is particularly desirable with airplanes of the latter type.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-80
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    Publication Date: 2019-08-26
    Description: The pressure distribution on the fuselage of a midwing airplane model was measured in the NACA 8-foot high speed wind tunnel at speeds from 140 to 440 miles per hour for lift coefficients ranging from -0.2 to 1.0. The primary purpose of the tests was to provide data showing the air pressures on various parts of the fuselage for use in structural design. The data may also be used for the design of scoops and vents. The results show that the highest negative pressures occurred near the wing and were more dependent on the wing than on the fuselage. At high speeds, the magnitude of the pressure coefficients as predicted from pressure coefficients determined experimentally at low speeds by application of the theoretical factor 1/(square root)1-M(exp 2) (where M is the ratio of the air speed to the speed of sound in air) may misrepresent the actual conditions. At the points where the maximum negative pressures ocurred, however, the variation of the pressure coefficients was in good agreement with the theoretical factor, indicating that this factor may afford satisfactory predictions of critical speed, at least for fuselages similar to the shape tested.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-133
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    Publication Date: 2019-08-26
    Description: Force tests were made of a 1/8-scale model of a twin-engine low-wing transport airplane in the NACA 8-foot high-speed wind tunnel to investigate compressibility and interference effects at speeds up to 450 miles per hour. In addition to tests of the standard arrangement of the model tests were made with several modifications designed to reduce the drag and to increase the critical speed. The results show serious increases in drag at critical speeds below 450 miles per hour due to the occurrence of compressibility burbles on the standard radial-engine cowlings, on sections of the wing as a result of wing-nacelle interference, and on the semi-retracted main landing wheels. The critical speed at which the shock occurred on the standard cowlings was 20 miles per hour lower in the presence of the fuselage than in the presence of the wing only. The drag of the complete model was reduced 25% at 300 miles per hour by completely retracting the landing gear, fairing the windshield irregularities, and substituting streamline nacelles (with allowance made for the proper amount of cooling-air flow) for the standard nacelle arrangement. The values of the critical Mach number were extended from 0.47 to 0.60 as a result of the aforementioned improvements. The principal purpose of the reported tests was to investigate the effect of compressibility on the drag of the component parts of a representative large airplane and on the overall drag of such an airplane. The influence of interference on compressibility effects was also studied. In addition, it was proposed to test several modifications of the standard component parts that gave promise of an improvement in aerodynamic characteristics.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-143
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    Publication Date: 2019-08-16
    Description: An analysis is made of the stability of an airplane with ailerons free, with particular attention to the motions when the ailerons have a tendency to float against the wind. The present analysis supersedes the aileron investigation contained in NACA Report No. 709. The equations of motion are first written to include yawing and sideslipping, and it is demonstrated that the principal effects of freeing the ailerons can be determined without regard to these motions. If the ailerons tend to float against the wind and have a high degree of aerodynamic balance, rolling oscillations, in addition to the normal lateral oscillations, are likely to occur. On the basis of the equations including only the rolling motion and the aileron deflection, formulas are derived for the stability and damping of the rolling oscillations in terms of the hinge moment derivatives and other characteristics of the ailerons and airplane. Charts are also presented showing the oscillatory regions and stability boundaries for a fictitious airplane of conventional proportions. The effects of friction in the control system are investigated and discussed. If the ailerons tend to trail with the wind, the condition for stable variation of stick force with aileron deflection is found to determine the amount of aerodynamic balance that may be used. If the ailerons tend to float against the wind, the period and damping of the rolling oscillations are found to be satisfactory (in a mass-balanced system) so long as the restoring moment is not completely balanced out. Unbalanced mass behind the hinge, however, has an unfavorable effect on the damping of the oscillations and so shifts the boundary that close aerodynamic balance may not be attainable.
    Keywords: Aircraft Design, Testing and Performance
    Type: AD-A301275 , NACA-TR-787 , NASA-TM-111361 , NAS 1.15:111361
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    Publication Date: 2019-07-13
    Description: This paper presents a series of tables for the simple and more common types of girders, similar to the tables given in handbooks under the heading "Strength of Materials," for determining the moments, deflections, etc., of simple beams. Instead of the uniform cross section there assumed, the formulas given here apply only to girders of "uniform strength," i.e., it is assumed that a girder is so dimensioned that a given load subjects it to a uniform stress throughout its whole length. This principle is particularly applicable to very strong structures. Girders of uniform strength are the lightest girders conceivable, because any girder, all of whose members are stressed to the limit, can not be surpassed by a lighter girder, if the two girders have the same form. The weight G of a member of length l, cross section F and specific gravity gamma is: G = Flgamma.
    Keywords: Aircraft Design, Testing and Performance
    Type: NACA-SR-3B , Zeitschrift fur Flugtechnik und Motorluftechiffahrt (Magazine for Aeronautical Engineering and Motorluftechniffahrt); 22; 15; 456-463
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 49 (1930), S. 385-413 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The structure of the living blood cells is described and the cells are classified in the following species of ascidians: Phallusia nigra, Ecteinascidia turbinata, Clavelina oblongata, Symplegma viride. Evidence for the genetio relationship of the various types of cells is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 49 (1930), S. 455-507 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: The history of the cytoplasmic components in the spermatogenesis of Gerris is, in general, like that which has been described in the Pentatomidae. The observations of fixed material have been checked by extensive studies of freshly teased preparations. During the spermatocyte growth period the chondriosomes undergo considerable increase in mass. During the maturation divisions the chondriosomes are remarkably constant in orientation with respect to the centrioles. The nebenkern arises by fusion of chondriosomes differentiated into chromophilic and chromophobic portions. The Golgi bodies of the earlier spermatocytes are vesicular bodies, the peripheries of which are osmiophilic. These are not visible in fresh preparations, but the masses resulting from their fusion in the late prophase of the first division are visible in the unfixed cells. The non-osmiophilic material inside these masses stains with neutral red in fresh preparations. Only the osmiophilic part of the Golgi masses is involved in the fragmentation to form dictyosomes. There is very suggestive evidence that the process of acrosome synthesis largely takes place inside the sac-like acroblast (Golgi apparatus). In the spermatid, material which stains, in fresh preparations, like the acroblast is never seen, except inside or attached to the acroblast, where it appears in the form of small spheres of ‘pro-acrosomic’ material, which fuse to form the acrosome.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 49 (1930), S. 579-619 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Haemichromis bimaculata is a tropical teleost fish which will produce eggs practically throughout the year at intervals of from three to four weeks. These eggs are of suitable size and character for embryological study, the features of special interest so far discovered being as follows: (1) The egg is oval; (2) it is attached to a substratum by its side, the blastopore being at one end; (3) the embryo always tends to develop along the side opposite that originally next to the substratum.Results obtained by reorienting the eggs previous to cleavage, and by centrifuging them, seem to show that the relation of the embryonic axis to the egg is determined either previous to laying or very soon afterward, possibly by the relation to the substratum, and is not subsequently affected by gravity or other known factors. There may be some tendency for the first cleavage plane and the sagittal plane of the embryo to coincide, but such coincidence is not at all constant or exact.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 50 (1930), S. 127-142 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Color changes in Palaemonetes had been found to be inhibited in the whole abdomen by occluding the dorsal abdominal artery. Inasmuch as these chromatic responses are brought about by means of circulating hormones, it should be possible, in view of early anatomical findings, for specific substances to reach the abdomen by way of the ventral abdominal artery which has been described for so many decapod crustaceans. This paper reports a degenerate ventral abdominal artery and a ventral continuation of the dorsal abdominal artery, the latter thus being distributed to practically the entire abdomen and therefore chiefly responsible for abdominal color-change phenomena.A method is given for injecting the arteries of small crustaceans, and the entire arterial system of Palaemonetes is described and figured. Several hitherto unreported vascular structures are noted: a plexus of blood vessels surrounding the supra-oesophageal ganglion, certain branches of the ophthalmic artery leading to the eyes, and various branches of the dorsal abdominal artery in the region of the telson and uropods. The forward flow of blood in the ventral portion of the abdomen in decapod crustaceans is held to be unique.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Journal of Morphology 50 (1930) 
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...