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The effect of the slipstream on an airplane wing

Description: The conditions which must be met at the slipstream boundary are developed, after which it is shown with the aid of the reflection method how these limiting conditions may be complied with in the case of an airfoil in a propeller slipstream in horizontal flow as well as for the propeller in yaw and with allowance for the slipstream rotation. In connection herewith, it is shown how the effective angles of attack and the circulation distribution with due regard to slipstream effect can be predicte… more
Date: November 1939
Creator: Franke, A. & Weinig, F.
Partner: UNT Libraries Government Documents Department
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Effect of Transition in Cross-Sectional Shape on the Development of the Velocity and Pressure Distribution of Turbulent Flow in Pipes

Description: With regard to the change in shape of the cross section while the area remains constant, no investigation results are as yet available. Such an investigation will be the subject of the present paper. For this purpose it is necessary to consider the velocity and pressure relations over each entire cross section so that we are confronted with a three-dimensional problem.
Date: August 1939
Creator: Mayer, Edwin
Partner: UNT Libraries Government Documents Department
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Effective Gust Structure at Low Altitudes as Determined From the Reactions of an Airplane

Description: "Measurements of gust structure and gust intensity were made in the lower levels of the atmosphere (0 to 3,500 ft.). An Aeronca C-2 airplane was used as the measuring instrument, the gust structure being derived from the recorded motions of the airplane. Data were also obtained on wind velocities and temperatures as functions of altitude for use in attempting to correlate the gust-structure data with various meteorological quantities" (p. 263).
Date: October 19, 1939
Creator: Donely, Philip
Partner: UNT Libraries Government Documents Department
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Effects of elevator nose shape, gap, balance, and tabs on the aerodynamic characteristics of a horizontal tail surface

Description: Results are presented showing the effects of gap, elevator, nose shape, balance, cut-out, and tabs on the aerodynamic characteristics of a horizontal tail surface tested in the NACA full-scale tunnel.
Date: April 27, 1939
Creator: Goett, Harry J. & Reeder, J. P.
Partner: UNT Libraries Government Documents Department
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The effects of partial-span slotted flaps on the aerodynamic characteristics of a rectangular and a tapered N.A.C.A. 23012 wing

Description: An investigation was made in the N.A.C.A. 7- by 10-foot wind tunnel to determine the aerodynamic characteristics of tapered and rectangular wings with partial-span slotted flaps. Two N.A.C.A. 23012 airfoils equipped with center-section and tip-section flaps were tested. The results showed that the changes in lift and drag due to changes in flap span for both rectangular and tapered wings having partial-span slotted flaps were similar to those for corresponding wings having partial-span split or… more
Date: July 1939
Creator: House, Rufus O.
Partner: UNT Libraries Government Documents Department
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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
Partner: UNT Libraries Government Documents Department
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The Effects of Some Surface Irregularities on Wing Drag

Description: "The N.A.C.A. has conducted tests to provide more complete data than were previously available for estimating the effects of common surface irregularities on wing drag. The irregularities investigated included: brazier-head and countersunk rivets, spot welds, several types of sheet-metal joints, and surface roughness. Tests were also conducted to determine the over-all effect of manufacturing irregularities incidental to riveted aluminum alloy and to spot-welded stainless-steel construction" (p… more
Date: March 1939
Creator: Hood, Manley J.
Partner: UNT Libraries Government Documents Department
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The Effects of Surface Waviness and of Rib Stitching on Wing Drag

Description: "Surface waviness and rib stitching have been investigated as part of a series of tests to determine the effects on wing drag of common surface irregularities. The tests were made in the N.A.C.A. 8-foot high-speed wind tunnel at Reynolds Numbers up to 17,000,000. The results of the tests showed that the waviness common to airplane wings will cause no serious increase in drag unless the waviness exists on the forward part of the wing, where it may cause premature transition or premature compress… more
Date: August 1939
Creator: Hood, Manley J.
Partner: UNT Libraries Government Documents Department
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An Electrical-Type Indicating Fuel Flowmeter

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 mete… more
Date: September 1939
Creator: Tozier, Robert E.
Partner: UNT Libraries Government Documents Department
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Engine Knock and Combustion Chamber Form

Description: The present report is confined to the effect of the combustion chamber shape on engine knock from three angles, namely: 1) The uniformity of flame-front movement as affected by chamber design and position of the spark plug; 2) The speed of advance of the flame as affected by turbulence and vibrations; 3) The reaction processes in the residual charge as affected by the walls.
Date: October 1939
Creator: Zinner, Karl
Partner: UNT Libraries Government Documents Department
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Engine Operation in Flight for Minimum Fuel Consumption

Description: "Engine and airplane performance data have been gathered from various sources and analyzed to determine indications of the most economical methods of flight operation from a consideration of fuel expenditure. The analysis includes the influence of such facts as fuel-air ratio, engine speed, engine knock, altitude, cylinder cooling, spark timing, and limits of cruising brake mean effective pressure. The results indicate that the cheapest power is obtained with approximately correct mixture at lo… more
Date: November 1939
Creator: Reuter, George
Partner: UNT Libraries Government Documents Department
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The Enlarged N.A.C.A. Tank, and Some of Its Work

Description: The most conspicuous of the features of the enlarged N.A.C.A. tank are derived directly from those of the original tank and owe their present form not only to the reasons for their first use but also to the experience obtained with them. As in the original tank, there are: 1) A basin of great length (new 2,880 feet); 2) Rails made of structural H beams, without machining; 3) A towing carriage of very high speed (now 80 mph maximum); 4) Rubber tires on all the wheels, pneumatic on the running wh… more
Date: November 1939
Creator: Truscott, Starr
Partner: UNT Libraries Government Documents Department
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Experimental and Analytical Investigation of a Monocoque Wing Model Loaded in Bending

Description: "Bending tests with transverse loads and with pure bending were undertaken on a double-web monocoque wing model in order to establish the relation between the state of stress and the results from the elementary bending theory. The longitudinal stresses in the stiffeners were measured with tensiometers and the shear stresses in the sheet were calculated from them. The measurements were made at both moderate loads with no buckles in the covering and at loads with which the critical stress in the … more
Date: October 1939
Creator: Schapitz, E.; Feller, H. & Köller, H.
Partner: UNT Libraries Government Documents Department
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Experimental Investigation of the Momentum Method for Determining Profile Drag

Description: Report presents the results of an experimental investigation conducted in the full-scale tunnel to determine the accuracy of the Jones and the Betz equations for computing profile drag from total and static pressure surveys in the wake of wings. Surveys were made behind 6 by 8-foot airfoils of the NACA 0009, and 0018 sections at zero lift and behind the NACA 0012 at positive lifts. The surveys were made at various spanwise positions and at distances behind the airfoil ranging from 0.05c to 3.00… more
Date: 1939
Creator: Goett, Harry J.
Partner: UNT Libraries Government Documents Department
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An Experimental Investigation of the Normal Acceleration of an Airplane Model in a Gust

Description: Note presenting an investigation in the gust tunnel to determine the influence of airplane wing loading, forward velocity, wing plan form, and the fuselage on the reaction of the airplane to a known gust. Tests were made for four values of gust velocity and for two gust gradients, specifically the sharp-edge gust and a gust rising linearly to full strength in a distance of several chord lengths.
Date: May 1939
Creator: Donely, Philip
Partner: UNT Libraries Government Documents Department
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Experimental study of deformation and of effective width in axially loaded sheet-stringer panels

Description: From Summary: "The deformation of two sheet-stringer panels subjected to end compression under carefully controlled end conditions was measured at a number of points and at a number of loads, most of which were above the load at which the sheet had begun to buckle. The two panels were identical except for the sheet, which was 0.70-inch 24st alclad for specimen 1 and 0.025-inch 24st aluminum alloy for specimen 6. A technique was developed for attaching Tuckerman optical strain gauges to the shee… more
Date: February 1939
Creator: Ramberg, Walter; McPherson, Albert E. & Levy, Sam
Partner: UNT Libraries Government Documents Department
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Experimental Study of Torsional Column Failure

Description: "Thirty-three 24ST aluminum-alloy 2- by 2- by 0.10-inch channels, with lengths ranging from 10 to 90 inches were tested at Stanford University in compression to obtain an experimental verification of the theoretical formulas for torsional failure developed by Eugene E. Lundquist of the N.A.C.A. The observed critical loads and twist-axis locations were sufficiently close to the values obtained from the formulas to establish the substantial validity of the latter. The differences between observed… more
Date: October 1939
Creator: Niles, Alfred S.
Partner: UNT Libraries Government Documents Department
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Experimental Verification of the Theory of Oscillating Airfoils

Description: "Measurements have been made of the lift on an airfoil in pitching oscillation with a continuous-recording, instantaneous-force balance. The experimental values for the phase difference between the angle of attack and the lift are shown to be in close agreement with theory" (p. 619).
Date: April 24, 1939
Creator: Silverstein, Abe & Joyner, Upshur T.
Partner: UNT Libraries Government Documents Department
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Experiments on a Slotted Wing

Description: The results of pressure distribution measurements that were made on a model wing section of a Fieseler F 5 R type airplane are presented. Comparison of those model tests with the corresponding flight tests indicates the limitations and also the advantages of wind tunnel investigations, the advantages being particularly that through the variety of measuring methods employed the more complicated flow conditions may also be clarified. A fact brought out in these tests is that even in the case of "… more
Date: March 1939
Creator: Ruden, P.
Partner: UNT Libraries Government Documents Department
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Experiments on the Recovery of Waste Heat in Cooling Ducts, Special Report

Description: Tests have been conducted in the N.A.C.A. full-scale wind tunnel to investigate the partial recovery of the heat energy which is apparently wasted in the cooling of aircraft engines. The results indicate that if the radiator is located in an expanded duct, a part of the energy lost in cooling is recovered; however, the energy recovery is not of practical importance up to airplane speeds of 400 miles per hour. Throttling of the duct flow occurs with heated radiators and must be considered in des… more
Date: May 1939
Creator: Silverstein, Abe
Partner: UNT Libraries Government Documents Department
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Flame Speeds and Energy Considerations for Explosions in a Spherical Bomb

Description: "Simultaneous measurements were made of the speed of flame and the rise in pressure during explosions of mixtures of carbon monoxide, normal heptane, iso-octane, and benzene in a 10-inch spherical bomb with central ignition. From these records, fundamental properties of the explosive mixtures, which are independent of the apparatus, were computed. The transformation velocity, or speed at which flame advances into and transforms the explosive mixture, increases with both the temperature and the … more
Date: September 28, 1939
Creator: Fiock, Ernest F.; Marvin, Charles F., Jr.; Caldwell, Frank R. & Roeder, Carl H.
Partner: UNT Libraries Government Documents Department
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A flight investigation of the distribution of ice-inhibiting fluids on a propeller blade

Description: Report presenting an investigation of the flow of ice-inhibiting fluids over the blade surfaces of a 12.5-foot-daimeter propeller in flight by discharging dyed fluids at various stations along the leading edges of the blades. The effects on the distribution of varying the fluid composition, the blade-surface roughness, and the orifice design were also observed.
Date: September 1939
Creator: Rodert, Lewis A.
Partner: UNT Libraries Government Documents Department
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Flight Tests of N.A.C.A. Nose-Slot Cowlings on the BFC-1 Airplane

Description: "The results of flight tests of four nose-slot cowling designs with several variations in each design are presented. The tests were made in the process of developing the nose-slot cowling. The results demonstrate that a nose-slot cowling may be successfully applied to an airplane and that it utilizes the increased slipstream velocity of low-speed operation to produce increased cooling pressure across the engine" (p. 1).
Date: August 1939
Creator: Stickle, George W.
Partner: UNT Libraries Government Documents Department
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Flight Tests of Retractable Ailerons on a Highly Tapered Wing

Description: "A flight investigation was conducted to determine the lateral-control characteristics of retractable ailerons installed on a highly tapered wing. The effectiveness of the ailerons in producing roll was measured at various air speeds with full-span plain flaps both neutral and deflected 45 degrees. The direction of the yawing moment created by the ailerons was also noted. The lateral control provided by the retractable ailerons used in this investigation was approximately the same as that obtai… more
Date: June 1939
Creator: Wetmore, J. W.
Partner: UNT Libraries Government Documents Department
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