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Effect of Propeller Operation on the Pitching Moments of Single-Engine Monoplanes

Description: Report presenting an investigation of the effects of propeller operation on pitching moments with particular reference to the effect of propeller forces, the field of flow in the slipstream, and the increments of lift on the wing and the tail. A procedure, directly applicable only to single-engine monoplanes without flaps, has been set up for predicting the effect of propeller operation on pitching moments as well.
Date: May 1941
Creator: Goett, Harry J. & Pass, H. R.
Item Type: Refine your search to only Report
open access

The Effect of Streamlining the Aterbody of an N.A.C.A. Cowling

Description: Report presenting an investigation of the drag and power cost associated with the changing of the nose of a nacelle from a streamline shape to a conventional cowling shape. Full-scale propellers and nacelles were used. The results of the tests showed that the streamline afterbody drag approached that of an airship form and that the added drag due to the open-nose cowling was only a quarter of the drag increase obtained with the other afterbody.
Date: December 1939
Creator: Stickle, George W.; Crigler, John L. & Naiman, Irven
Item Type: Refine your search to only Report
open access

Effect of the Lift Coefficient on Propeller Flutter

Description: Report presenting flutter of propellers at high angles of attack and flutter data obtained in connection with tests of models of large wind-tunnel propellers. The stall flutter speed was found to be much lower than the calculated classical flutter speed. That flutter speed is only obtainable if the propeller operates at the ideal angle of zero twist.
Date: July 1945
Creator: Theodorsen, Theodore & Regier, Arthur A.
Item Type: Refine your search to only Report
open access

Effect of tilt of the propeller axis on the longitudinal-stability characteristics of single-engine airplanes

Description: Report presenting the results of tests of a model of a single-engine airplane with two different tilts of the propeller axis. The results indicate that on a typical design, a 5 degree downward tilt of the propeller axis will considerably reduce the destabilizing effects of power.
Date: November 1944
Creator: Goett, Harry J. & Delany, Noel K.
Item Type: Refine your search to only Report
open access

Effect of Wing Modifications on the Longitudinal Stability of a Tailless All-Wing Airplane Model

Description: Report presenting an investigation of the power-off longitudinal stability characteristics of a tailless all-wing airplane model with various wing modifications in the free-flight tunnel. The results indicated that changes in the tip plan form or rotation of the wing tips did not appreciably reduce the instability at high lift coefficients.
Date: September 1945
Creator: Seacord, Charles L., Jr. & Ankenbruck, Herman O.
Item Type: Refine your search to only Report
open access

The Effect on Stability and Control of a Pusher Propeller Behind Conventional Tail Surfaces as Determined by Tests of a Powered Model in the Free-Flight Tunnel

Description: Report presenting an investigation of the effects on stability and control of a pusher propeller behind conventional horizontal and vertical tail surfaces in the free-flight tunnel by tests of a scale model of a submerged-engine pusher airplane. The investigation consisted of flight and balance tests at windmilling and high-power conditions with a partial-span Zap extensible flap extended and retracted. Results regarding the longitudinal stability, longitudinal control, stalling characteristics… more
Date: January 1943
Creator: Campbell, John P. & Hollingworth, Thomas A.
Item Type: Refine your search to only Report
open access

Effects of Compressibility on the Maximum Lift Characteristics and Spanwise Load Distribution of a 12-Foot-Span Fighter-Type Wing of NACA 230-Series Airfoil Sections

Description: Lift characteristics and pressure distribution for a NACA 230 wing were investigated for an angle of attack range of from -10 to +24 degrees and Mach range of from 0.2 to 0.7. Maximum lift coefficient increased up to a Mach number of 0.3, decreased rapidly to a Mach number of 0.55, and then decreased moderately. At high speeds, maximum lift coefficient was reached at from 10 to 12 degrees beyond the stalling angle. In high-speed stalls, resultant load underwent a moderate shift outward.
Date: November 1945
Creator: Pearson, E. O., Jr.; Evans, A. J. & West, F. E., Jr.
Item Type: Refine your search to only Report
open access

Effects of Direction of Propeller Rotation on the Longitudinal Stability of the 1/10-Scale Model of the North American XB-28 Airplane With Flaps Neutral

Description: "The effects of direction of propeller rotation on factors affecting the longitudinal stability of the XB-28 airplane were measured on a 1/10-scale model in the 7- by 10-foot tunnel of the Ames Aeronautical Laboratory. The main effect observed was that caused by regions of high downwash behind the nacelles (power off as well as power on with flaps neutral). The optimum direction of propeller rotation, both propellers rotating up toward the fuselage, shifted this region off the horizontal tail a… more
Date: June 1942
Creator: Delany, Noel K.
Item Type: Refine your search to only Report
open access

The effects of hub drag, solidity, dual rotation, and number of blades upon the efficiency of high-pitch propellers

Description: Report presenting an investigation of the effects of hub drag, solidity, dual rotation, and number of blades on the efficiency of high-pitch propellers. Testing occurred with two, three, four, and six-blade single propellers and four and six-blade dual-rotating propellers equipped with spinners and tested at a range of blade angles from 35 to 65 degrees. Results regarding a comparison of the large and small spinners, effects of spinners, comparison of constant-speed propellers, characteristics … more
Date: October 1941
Creator: Reid, Elliott G.
Item Type: Refine your search to only Report
open access

Effects of Mean-Line Loading on the Aerodynamic Characteristics of Some Low-Drag Airfoils

Description: "The effect of variations in the type of mean line on the section characteristics of several representative NACA low-drag airfoils was investigated. The test results are compared with theoretical predictions and indicate trends that facilitate the choice of mean line in the absence of tests" (p. 1).
Date: September 1943
Creator: Davidson, Milton & Turner, Harold R., Jr.
Item Type: Refine your search to only Report
open access

Effects of Propellers and of Vibration on the Extent of Laminar Flow on the NACA 27-212 Airfoil

Description: Report presenting an investigation of the effects of propellers and of vibration on the extent of laminar flow on the NACA 27-212 airfoil by testing the airfoil in conjunction with a tractor and a pusher propeller and with a mechanical vibrator. The results show that neither the pusher propeller nor vibration with amplitudes up to 0.094 inch and with a frequency of 1650 cycles per minute had any consequential effect on the extent of laminar flow but that the tractor propeller had a very pronoun… more
Date: October 1939
Creator: Hood, Manley J. & Gaydos, M. Edward
Item Type: Refine your search to only Report
open access

The Effects of Roughness at High Reynolds Numbers on the Lift and Drag Characteristics of Three Thick Airfoils

Description: "In connection with studies of airfoils applicable to large high-speed aircraft, the effects of roughness on three 22-percent-thick airfoils were investigated. The tests were made over a range of Reynolds number from about 6 to 26 x 10(exp 6) for the airfoils smooth and with roughness strips applied to the surfaces. The results indicated that for the roughened models the scale effect was generally favorable" (p. 1).
Date: August 1944
Creator: Abbott, Frank T., Jr. & Turner, Harold R., Jr.
Item Type: Refine your search to only Report
open access

Effects of Simulated Ice Formation on the Aerodynamic Characteristics of an Airfoil

Description: Report presenting an investigation of the size and distribution of ice particles on the wings of aircraft and how they affect the aerodynamic characteristics. A simulated ice formation was generated from survey information received from aircraft pilots and was tested to determine the impact on the lift characteristics.
Date: May 1938
Creator: Gulick, Beverly G.
Item Type: Refine your search to only Report
open access

Effects on Low-Speed Spray Characteristics of Various Modifications to a Powered Model of the Boeing XPBB-1 Flying Boat

Description: Report presenting tests of a powered model of the Boeing XPBB-1 flying boat in order to observe the effects of trim and powered propellers, of lengths of forebody and afterbody, and of various spray strips on the low-speed spray characteristics. The effects of powering the propellers were to lower the trim and to pick up spray that would not strike the propeller disks when the propellers were windmilling. Results regarding the effects of trim and powered propellers, effect of length of forebody… more
Date: June 1945
Creator: King, Douglas A. & Mas, Newton A.
Item Type: Refine your search to only Report
open access

Efficiency tests of a single-stage impulse turbine having an 11.0-inch pitch-line diameter wheel with air as the driving fluid

Description: Report presenting efficiency tests on a single-stage impulse turbine with an 11.0-inch pitch-line diameter wheel and a fabricated nozzle diaphragm with air at moderate temperature as the driving fluid. Results regarding the variation of turbine efficiency with blade-to-jet speed ratio over a range of turbine pressure ratios and maximum efficiency are provided.
Date: April 1945
Creator: Gabriel, David S. & Carman, L. Robert
Item Type: Refine your search to only Report
open access

An Electron and X-Ray Diffraction Investigation of Surface Changes on Nitrided-Steel Piston Rings During Engine Operation in Nitrided-Steel Cylinders Barrels

Description: Report presenting an examination of new and used nitrided-steel piston rings by electron and X-ray diffraction in a study of the surface changes produced during engine operation. Both new and used rings, examined after degreasing, gave an electron-diffraction pattern consisting of diffuse bands: those from used rings fell at the usual positions of the bands from polished metal surfaces.
Date: March 1945
Creator: Good, J. N. & Brockway, L. O.
Item Type: Refine your search to only Report
open access

An Electron-Diffraction Examination of Cast-Iron Piston Rings From Single-Cylinder Aircraft Engine Tests

Description: Report presenting an electron-diffraction examination of cast-iron piston rings used in a single-cylinder test engine, which showed the presence of a layer of graphite covering the surface. The wear curves from the rings studied had shown variation from high rates to very low rates of wear.
Date: February 1945
Creator: Nowick, A. S. & Brockway, L. O.
Item Type: Refine your search to only Report
open access

Engine and inspection tests of methyl tert-butyl ether as a component of aviation fuel

Description: Report presenting an investigation of the suitability of methyl tert-butyl ether as a component of aviation fuel from considerations of knock-limited performance tests and laboratory inspection tests. Data were obtained from testing on the 17.6 engine under supercharged conditions with fuel blends containing 10 and 20 percent methyl tert-butyl ether. Results regarding small-scale-engine data, full-scale-engine data, and inspection data are provided.
Date: August 1944
Creator: Barnett, Henry C.; Meyer, Carl L. & Jones, Anthony W.
Item Type: Refine your search to only Report
open access

Estimation of Critical Speeds of Airfoils and Streamline Bodies

Description: Report presenting methods and charts for estimating the critical compressibility speeds of a large number of airfoils and streamline bodies. The systematic effects of thickness, thickness distribution, camber, camber location, leading-edge radius, and lift coefficient are considered. The results indicate that with a given lift coefficient, the thickness of the airfoil or of the body is the primary factor controlling its critical speed.
Date: March 1940
Creator: Robinson, Russell G. & Wright, Ray H.
Item Type: Refine your search to only Report
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