16 Matching Results

Search Results

Effect of Orifice Length-Diameter Ratio on Spray Characteristics

Description: "The effect of variations of orifice length to diameter ratio on spray characteristics was determined for a 0.014-inch and a 0.040-inch orifice for ratio of 0.5 to 4.0. The nozzles containing the orifices were mounted in an injection valve and tested with a plan stem and with a helically grooved stem. The injection pressure was varied from 4000 to 8000 pounds per square inch. The air density into which the fuel was sprayed was varied from the density obtained with a pressure of 60 pounds per square inch to the density obtained with a pressure of 250 pounds per square inch at room temperature" (p. 1).
Date: October 1930
Creator: Gelalles, A. G.
Partner: UNT Libraries Government Documents Department

Methods for the Identification of Aircraft Tubing of Plain Carbon Steel and Chromium-Molybdenum Steel

Description: The survey of the possibilities for distinguishing between plain carbon and chromium-molybdenum steel tubing included the Herbert pendulum hardness, magnetic, sparks, and chemical tests. The Herbert pendulum test has the disadvantages of all hardness tests in being limited to factory use and being applicable only to scale-free, normalized material. The small difference in the range of hardness values between plain carbon and chromium-molybdenum steels is likewise a disadvantage.
Date: October 1930
Creator: Mutchler, W. H. & Buzzard, R. W.
Partner: UNT Libraries Government Documents Department

Analytical Determination of the Load on a Trailing Edge Flap

Description: From Summary: "This report presents a theoretical analysis of the lift on a trailing edge flap. An analytical expression has been derived which enables the computation of the flap load coefficient. The theoretical results seem to show a fair agreement with the meager experimental results which are available."
Date: October 1930
Creator: Pinkerton, Robert M.
Partner: UNT Libraries Government Documents Department

An Accurate Method of Measuring the Moments of Inertia of Airplanes

Description: From Summary: "This note contains a description of an improved apparatus and procedure used by the NACA for determining the moments of inertia of airplanes. The method used, based on the pendulum theory, is similar to that previously used, but a recent investigation of its accuracy has resulted in the improvements described herein. The error, when using the new apparatus and procedure, has been found to be of the order of 1 per cent."
Date: October 1930
Creator: Miller, M. P.
Partner: UNT Libraries Government Documents Department

The Behm Acoustic Sounder for Airplanes With Reference to Its Accuracy

Description: Relative altimetry is of great importance for increasing the safety in aerial transportation, because it makes possible safe flying at night, by poor visibility, and when landing. Among the instruments of this type is the Behm sounder, which operates on an acoustic principle. Acoustic altimetry in general and the Behn sounder, in particular, are covered in this report.
Date: October 1930
Creator: Schreiber, Ernest
Partner: UNT Libraries Government Documents Department

Counter-Propeller

Description: A counter-propeller is a fixed propeller smaller than the main propeller, mounted either fore or aft of the latter and performing the function of changing the direction of motion of the fluid filaments, which naturally tend to adopt a helicoidal form. This paper presents a consideration of the real advantage of counter-propellers on aircraft and the best shape of the blades. First, the author determines the possible energy absorption by the tangential increments. This process will be facilitated by the examination of the polygons of the relative velocities fore and aft of the generic section, of radius r, of one of the blades of the propeller.
Date: October 1930
Creator: de Caria, Ugo
Partner: UNT Libraries Government Documents Department

Present Status of Aircraft Instruments

Description: This report gives a brief description of the present state of development and of the performance characteristics of instruments included in the following group: speed instruments, altitude instruments, navigation instruments, power-plant instruments, oxygen instruments, instruments for aerial photography, fog-flying instruments, general problems, summary of instrument and research problems. The items considered under performance include sensitivity, scale errors, effects of temperature and pressure, effects of acceleration and vibration, time lag, damping, leaks, elastic defects, and friction.
Date: October 9, 1930
Creator: Subcommittee on Instruments
Partner: UNT Libraries Government Documents Department

A method of flight measurement of spins

Description: A method is described involving the use of recording turn meters and accelerometers and a sensitive altimeter, by means of which all of the physical quantities necessary for the complete determination of the flight path, motion, attitude, forces, and couples of a fully developed spin can be obtained in flight. Data are given for several spins of two training type airplanes which indicate that the accuracy of the results obtained with the method is satisfactory.
Date: October 7, 1930
Creator: Soulé, Hartley A. & Scudder, Nathan F.
Partner: UNT Libraries Government Documents Department

Static, Drop, and Flight Tests on Musselman Type Airwheels

Description: The purpose of this investigation was to obtain quantitative information on the shock-reducing and energy-dissipating qualities of a set of 30 by 13-6 Musselman type airwheels. The investigation consisted of static, drop, and flight tests. The static tests were made with inflation pressures of approximately 0, 5, 10, 15, 20, and 25 pounds per square inch and loadings up to 9,600 pounds.
Date: October 8, 1930
Creator: Peck, William C. & Beard, Albert P.
Partner: UNT Libraries Government Documents Department

Comparison of full-scale propellers having R.A.F.-6 and Clark Y airfoil sections

Description: In this report the efficiencies of two series of propellers having two types of blade sections are compared. Six full-scale propellers were used, three having R. A. F.-6 and three Clark Y airfoil sections with thickness/chord ratios of 0.06, 0.08, and 0.10. The propellers were tested at five pitch setting, which covered the range ordinarily used in practice. The propellers having the Clark Y sections gave the highest peak efficiency at the low pitch settings. At the high pitch settings, the propellers with R. A. F.-6 sections gave about the same maximum efficiency as the Clark Y propellers and were more efficient for the conditions of climb and take-off.
Date: October 8, 1930
Creator: Freeman, Hugh B.
Partner: UNT Libraries Government Documents Department

Elastic Instability of Members Having Sections Common in Aircraft Construction

Description: "Two fundamental problems of elastic stability are discussed in this report. In part one formulas are given for calculating the critical stress at which a thin, outstanding flange of a compression member will either wrinkle into several waves or form into a single half wave and twist the member about its longitudinal axis. In part two the lateral buckling of beams is discussed" (p. 373).
Date: October 15, 1930
Creator: Trayer, George W. & March, H. W.
Partner: UNT Libraries Government Documents Department

Velocity Distribution in the Boundary Layer of a Submerged Plate

Description: This report deals with the measurement of the velocity distribution of the air in the velocity of a plate placed parallel to the air flow. The measurements took place in a small wind tunnel where the diameter of the entrance cone is 30 cm and the length of the free jet between the entrance and exit cones is about 2.5 m. The measurements were made in the free jet where the static pressure was constant, which was essential for the method of measurement used.
Date: October 1930
Creator: Hansen, M.
Partner: UNT Libraries Government Documents Department

Westland "Wessex" Commercial Airplane (British): A High-Wing Semicantilever Monoplane

Description: Circular presenting a description of the Westland Wessex, which differs from other airplanes of its class because of the mounting of the outboard engines on outriggers from the fuselage and the placing of the engines in such a way that the slipstream does not interfere with the movement of the wing. A description of the design, flight characteristics, blueprints, and photographs are provided.
Date: October 1930
Partner: UNT Libraries Government Documents Department