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Critical shear stress of an infinitely long flat plate with equal elastic restraints against rotation along the parallel edges

Description: Report presenting a chart for the values of the coefficient in the formula for the critical shear stress at which buckling may be expected to occur in an infinitely long flat plate with parallel edges. An approximate method for the evaluation of the critical shear stress when the elastic restraints on the two parallel edges are not equal is also presented.
Date: November 1943
Creator: Stowell, Elbridge Z.
open access

Full-scale tunnel investigation of the pressure distribution over the tail of the P-47B airplane

Description: Report presenting measurements made of the pressures of the tail surfaces of the Republic Aviation Corporation P-47B airplane in the full-scale tunnel. Pressures were measured over the horizontal and vertical tail surfaces for several angles of attack and angles of yaw with numerous control-surface deflections to provide a check on the design loads. Results regarding the normal-force coefficients and predictions of forces on horizontal tail surfaces are provided.
Date: May 1943
Creator: Dingeldein, Richard C.
open access

Limitations of lifting-line theory for estimation of aileron hinge-moment characteristics

Description: Report presenting hinge-moment parameters for several typical ailerons, which were calculated from section data with the aspect-ratio correlation as usually determined from lifting-line theory. The calculations showed that the agreement between experimental and calculated results was unsatisfactory.
Date: December 1943
Creator: Swanson, Robert S. & Gillis, Clarence L.
open access

Vibration Surveys of the P-40 Rudder and Fin-Rudder Assembly

Description: "The following surveys on the vibration response of the P-40 rudder and fin-rudder assembly were conducted during the fall of 1942 for the purpose of obtaining information on the flutter characteristics of high-speed airplanes of known performance. The tests on the rudder alone were made with the rudder suspended in a floating condition; the tests on the fin-rudder unit were made with the fin rigidly fastened to a concrete base" (p. 1). A variety of figures and diagrams for the assembly are pro… more
Date: April 1943
Creator: Theodorsen, Theodore & Regier, Arthur A.
open access

Preliminary Vibration and Flutter Studies on P-47 Tail

Description: Report presenting a report illustrated by photographs and vibration records on the failure of the P-47 rudder in the high-speed tunnel at a true speed of 468 miles per hour and a density corresponding to 9000 feet altitude. The fin-rudder unit was tested as being at least representative of the tail design of the P-47 airplane.
Date: August 1943
Creator: Theodorsen, Theodore
open access

Vibration Surveys of the P-47-B Rudder and Fin-Rudder Assembly

Description: Report presenting a study of the flutter characteristics of the P-47 tail assembly, which included replacing the original fabric-covered rudder with a metal-covered rudder and reinforcing the fin. Figures are provided for different configurations and the cycles per second under the same conditions are provided.
Date: April 1943
Creator: Theodorsen, Theodore & Regier, Arthur A.
open access

Wind-tunnel tests of ailerons at various speeds 2: ailerons of 0.20 airfoil chord and true contour with 0.60 aileron-chord sealed internal balance on the NACA 66,2-216 airfoil

Description: Report presenting hinge-moment, lift, pressure difference across the balance, and pressure-distribution measurements in the two-dimensional test section of the stability tunnel on a 0.60 aileron-chord sealed internal-balance aileron on a specified NACA airfoil. The primary test objective was to determine the effect of speed on the action of the aileron.
Date: June 1943
Creator: Denaci, H. G. & Bird, J. D.
open access

Wind-Tunnel Tests of Ailerons at Various Speeds 3: Ailerons of 0.20 Airfoil Chord and True Contour With 0.35-Aileron-Chord Frise Balance on the NACA 23012 Airfoil

Description: Report presenting hinge moment, lift, and pressure-distribution measurements made on a Frise aileron on an NACA 23012 airfoil in the two-dimensional test section of the stability tunnel. Speeds up to 360 miles per hour corresponding to a Mach number of about 0.470 were used.
Date: September 1943
Creator: Letko, W. & Kemp, W. B.
open access

Wind Tunnel Tests of Ailerons at Various Speeds 4: Ailerons of 0.20 Airfoil Chord and True Contour With 0.35 Aileron-Chord Extreme Blunt-Nose Balance on the NACA 23012 Airfoil

Description: Report presenting tests made on an NACA 23012 airfoil fitted with a 20-percent-chord, true-contour aileron with 35-percent-chord, extreme blunt-nose balance. The primary purpose of the investigation was to determine the variation of the aerodynamic characteristics of this type of aileron with airspeed; the effect of variations of gap width and balance-nose radii was also investigated. Results regarding hinge moments, lift, and pitching-moment coefficients are provided.
Date: August 1943
Creator: Anderson, R. A.
open access

Wind-Tunnel Investigation of a Plain Aileron with Various Trailing-Edge Modifications on a Tapered Wing 3: Ailerons with Simple and Spring-Linked Balancing Tabs

Description: Aerodynamics data are obtained for the design of linked balancing tabs and effect of varied tab span and location to produce suitable lateral control characteristics with reasonable stick pressures for high-speed aircraft. Simple and spring-linked balancing tabs may considerably reduce control pressures if aileron system is designed for low maximum aileron deflection. Spring-linked tabs also decrease variation of stick pressure with speed and impart better controlllability at low speeds.
Date: January 1943
Creator: Purser, Paul E. & Rogallo, F. M.
open access

A Study of the Effects of Radii of Gyration and Altitude on Aileron Effectiveness at High Speed

Description: "The variation in the necessary aileron control and in the time required to bank to 45 degrees and 90 degrees with altitude and radii of gyration for a typical fighter or a pursuit airplane have been computed and are presented herein." The lateral motions and impact pressure for several conditions of flight are provided. The report concludes that "the aileron system...should be designed for rolling-moment requirements at high altitude and the hinge-moment limitations at low altitude".
Date: April 1943
Creator: Fehlner, Leo F.
open access

Wind Tunnel Tests of Ailerons at Various Speeds 1: Ailerons of 0.20 Airfoil Chord and True Contour With 0.35 Aileron-Chord Extreme Blunt Nose Balance on the NACA 66,2-216 Airfoil

Description: "Hinge-moment, lift, and pressure-distribution measurements were made in the two-dimensional test section of the NACA stability tunnel on a blunt-nose balance-type aileron on an NACA 66,2-216 airfoil at speeds up to 360 miles per hour corresponding to a Mach number of 0.475. The tests were made primarily to determine the effect of speed on the action of this type of aileron. The balance-nose radii of the aileron were varied from 0 to 0.02 of the airfoil chord and the gap width was varied from 0… more
Date: June 1943
Creator: Letko, W.; Denaci, H. G. & Freed, C.
open access

Wind-tunnel investigation of a plain aileron with thickened and beveled trailing edges on a tapered low-drag wing

Description: Report presenting an investigation in the 7- by 10-foot tunnel of various modifications of the trailing-edge portion of a 0.20-chord plain aileron on a partial-span model of a tapered low-drag wing. The modifications tested included various amounts of symmetrical and unsymmetrical thickening and beveling of the aileron trailing edge. Results regarding coefficients and corrections, characteristics with ailerons neutral, characteristics with ailerons deflected, aileron trim characteristics, and e… more
Date: January 1943
Creator: Purser, Paul E. & McKee, John W.
open access

Wind-Tunnel Investigation of the Characteristics of Blunt-Nose Ailerons on a Tapered Wing

Description: Characteristics are determined for various modifications of 0.155-chord blunt-nose aileron on semispan model of tapered fighter plane wing. Ailerons with 40 percent nose balance reduced high-speed stick forces. Increased balance chord increases effectiveness and reduces high-speed stick forces. Increased balance chord increases effectiveness and reduces adverse effects of gap at aileron hose. Increase of nose radii increased negative slope of curve hinge-movement coefficient plotted against def… more
Date: February 1943
Creator: Purser, Paul E. & Toll, Thomas A.
open access

NACA Procedure for Flight Tests of Aileron Characteristics of Airplanes

Description: Report describes the standard procedure that NACA used for evaluating the aileron characteristics of airplanes. The variables measured in the testing are rolling velocity, aileron positions, aileron stick forces or tangential wheel force, indicated airspeed, altitude, free-air temperature, and rudder position. The step-by-step flight procedure is described and information regarding evaluation of the control data and general suggestions is included.
Date: July 1943
Creator: Johnson, Harold I.
open access

Some Systematic Model Experiments of the Bow-Spray Characteristics of Flying-Boat Hulls Operating at Low Speeds in Waves

Description: Report discusses the results of testing on several models of flying boats, the XPB2M-1, the XPBB-1, the JRM-1, and 11 other models to determine the effect of bow form on the amount of spray thrown onto the windshield of a flying boat in rough water. Several recommendations for reducing the height and volume of spray are provided. Any change in the hull form that softens the impact between the hull and waves seems to reduce the spray.
Date: December 1943
Creator: Locke, F. W. S., Jr.
open access

An investigation of aircraft heaters 13: performance of corrugated and noncorrugated fluted type exhaust gas-air heat exchangers

Description: Report presenting thermal and static pressure-drop performance data on three fluted-type heat exchangers. Two of the heaters used corrugated surfaces along the fluid passages and the third one was constructed with non-corrugated surfaces. Results regarding a comparison of results on the noncorrugated heater using two different air shrouds, heat transfer, isothermal static pressure drop, nonisothermal static pressure drop, and heater surface temperatures are provided.
Date: August 1943
Creator: Boelter, L. M. K.; Guibert, A. G.; Miller, M. A. & Morrin, E. H.
open access

Aerodynamic and Hydrodynamic Tests of a Family of Models of Flying-Boat Hulls Derived From a Streamline Body: NACA Model 84 Series

Description: Report presenting a series of related flying-boat hull forms with various combinations of aerodynamic and hydrodynamic requirements that were tested in an NACA tank and high-speed tunnel. Effects explored included varying the height of the bow, varying the height of the stern, increasing the angle of dead rise at the bow, decreasing the angle of dead rise on the afterbody, increasing the depth of step, increasing the angle of afterbody keel, adding chine flare, adding a third planing surface, a… more
Date: September 1943
Creator: Parkinson, John B.; Olson, Roland E.; Draley, Eugene C. & Luoma, Arvo A.
open access

Wind-tunnel tests of four full-scale seaplane floats

Description: Report presenting wind tunnel testing of four full-scale seaplane floats to determine the aerodynamic characteristics of the floats and to evaluate several drag-reducing refinements. Four floats were investigated; two differed only in external details like flush rivets, while one was the type used on twin-float installations. The variation of lift, drag, and pitching moment with pitch angle are presented for each float.
Date: July 1943
Creator: Conway, Robert N. & Maynard, Julian D.
open access

An investigation of aircraft heaters 10: measured and predicted performance of a fluted-type exhaust gas and air heat exchanger

Description: Report presenting performance data on a small exhaust gas and air heat exchanger. The heat transfer rates were measured using about 8000 pounds per hour of exhaust gas and 4300 pounds per hour of ventilating air. The thermal performance of heater no. 2 can be estimated to 3 to 17 percent by use of the method described in the report.
Date: March 1943
Creator: Boelter, L. M. K.; Dennison, H. G.; Guibert, A. G. & Morrin, E. H.
open access

An investigation of aircraft heaters 11: measured and predicted performance of a slotted-fin exhaust gas and air heat exchanger

Description: Report presenting the thermal and pressure drop performance data of a slotted-fin Stewart-Warner exhaust gas and ventilating air heat exchanger. Three different crossflow air shrouds were used in testing. The rate of heat transfer was about the same for each shroud, but the static pressure drops varied greatly.
Date: April 1943
Creator: Boelter, L. M. K.; Miller, M. A.; Sharp, W. H. & Morrin, E. H.
open access

An Investigation of Aircraft Heaters 8: A Simplified Method for the Calculation of the Unit Thermal Conductance Over Wings

Description: Report presenting a simplified approximate method of calculating the unit thermal conductance along an airfoil as a function of distance from the leading edge, by use of heat transfer data for smooth cylinders and smooth flat plates. Several examples are used in order to show the effectiveness of the method.
Date: March 1943
Creator: Martinelli, R. C.; Guibert, A. G.; Morrin, E. H. & Boelter, L. M. K.
open access

Wind-Tunnel Tests of a Piston-Type Control Booster on an Airfoil and Aileron Model

Description: "Measurements of control moments were made in the NACA stability tunnel to determine the operational characteristics of a piston-type control booster on an aileron. The booster was so constructed and installed that pressures picked up from the air stream below the wing acted on a pair of pistons. The data are presented in the form of curves of pressure coefficients acting on the pistons, hinge-moment coefficients, and booster coefficients plotted against aileron deflection" (p. 1).
Date: November 1943
Creator: Bird, J. D. & Mendelsohn, Robert A.
open access

Flight tests of beveled-trailing-edge ailerons with various modifications on a North American XP-51 airplane (AAF No.41-38)

Description: Report presenting flight testing using a North American XP-51 airplane with several arrangements of beveled-trailing-edge ailerons to determine the most satisfactory arrangement. Results regarding the aileron configuration, trimming tabs, and factors affecting symmetry of aileron characteristics are provided.
Date: December 1943
Creator: White, Maurice D. & Hoover, Herbert H.
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