116 Matching Results

Search Results

prev Results: 73 - 96 next
open access

Variation of Hydrodynamic Impact Loads With Flight-Path Angle for a Prismatic Float at 12 Degree Trim and With a 22-1/2 Degree Angle of Dead Rise

Description: Report discusses the results of testing "to determine the relationship between impact normal acceleration and flight-path angle for seaplanes landing on smooth water" (from Summary). The tests were performed at 12 degrees trim, 22.5 degree angle of dead rise, and a total weight of 1100 pounds. The effect on the maximum impact normal acceleration and the effects of immersion on acceleration are described.
Date: February 1946
Creator: Batterson, Sidney A.
Partner: UNT Libraries Government Documents Department
open access

Preliminary Tank Experiments With a Hydrofoil on a Planing-Tail Seaplane Hull

Description: Report describes exploratory testing to determine the feasibility of using a hydrofoil with a type of flying boat afterbody called a planing tail. Several hydrofoil locations were examined, including no hydrofoil, and the effects of resistance characteristics were charted. The researchers concluded that it is possible to add a single hydrofoil to that type of afterbody to provide additional hydrodynamic lift without introducing instability.
Date: March 1944
Creator: Wadlin, Kenneth L.
Partner: UNT Libraries Government Documents Department
open access

Landing Characteristics of a Model of a Flying Boat With the Depth of Step Reduced to Zero by Means of a Retractable Planing Flap

Description: "A model of a flying boat was tested to determine the landing characteristics when the depth of the step was reduced to zero by means of a retractable planing flap on the forebody" (p. 4). The results of stability and resistance testing are presented.
Date: February 1944
Creator: Benson, James M. & Freihofner, Anton
Partner: UNT Libraries Government Documents Department
open access

A Description of the Ju 88 Airplane Anti-Icing Equipment

Description: Bulletin presenting an examination of a part of the anti-icing equipment for a Ju 88 airplane, including exhaust-air heat exchangers, control valves, air duct system, and air-heated wing panels. Testing was performed on the components and indicated that the thermal ice-prevention equipment can maintain the outer-wing panel free from ice.
Date: September 1942
Creator: Rodert, Lewis A. & Jackson, Richard
Partner: UNT Libraries Government Documents Department
open access

Static-Pressure Error of an Airspeed Installation on an Airplane in High-Speed Dives and Pullouts

Description: "Tests were made in high-speed dives and pull-outs to determine, by combined radar-optical tracking equipment, the static-pressure error of an airspeed-head installation on a P-51B airplane." The equipment used and testing procedure are described. The variation of static-pressure error is provided for several ranges of airplane lift coefficient.
Date: February 1946
Creator: Zalovcik, John A. & Wood, Clotaire
Partner: UNT Libraries Government Documents Department
open access

Flight investigation of a stall-warning indicator for operation under icing conditions

Description: Report presenting an investigation to determine whether some characteristic of the boundary layer could be used to provide warning of the increase in stalling speed of a wing caused by ice formations on the leading edge. Results were analyzed by referring the total pressures at the rake to the free-stream total pressure, static pressure at the rake, free-stream static pressure, and static pressure from wind-tip swiveling head.
Date: July 1942
Creator: Jones, Alun R. & Zalovcik, John A.
Partner: UNT Libraries Government Documents Department
open access

Determination of Iron Contamination of Used Lubricating Oil for Use in Measuring Rates of Wear in Aircraft Engines

Description: Report discusses methods of determining the iron contamination of used lubricating oil in order to study wear rates of piston rings and cylinder barrels of aircraft engines. Two methods of separating iron from used lubricating oil are presented. The results of the analyses of the oil are presented and the methods are evaluated.
Date: March 1944
Creator: Tischler, Adelbert O.
Partner: UNT Libraries Government Documents Department
open access

The Effect of Oil Consumption and Piston Cooling on Knock-Limited Aircraft-Engine Performance

Description: Report discusses the "effects of oil introduced into the combustion chamber and of oil-spray piston cooling on the knock-limited performance of aircraft engines" (from Summary). A CFR engine and Allison V-1710 cylinder were used to test the rate of oil consumption, knock, and knock-limited brake mean effective pressure.
Date: May 1944
Creator: Huppert, Merle C.; Imming, Harry S. & Richard, Paul H.
Partner: UNT Libraries Government Documents Department
open access

An Electronic Indicator for Angular Velocity and Acceleration

Description: "An electronic circuit for instantaneously indicating angular velocity and acceleration, both positive and negative, of rotating masses is described; readings are taken on electrical indicating meters. The indicator is described in terms of general application. A circuit diagram, calibration curves, and a mathematical analysis of the differentiation circuit are included" (p. 1).
Date: August 1944
Creator: Krebs, Richard P.
Partner: UNT Libraries Government Documents Department
open access

The NACA Balanced-Diaphragm Dynamometer-Torque Indicator

Description: Report describes a balanced-diaphragm device for measuring dynamometer torque of single-cylinder or multicylinder engines that was developed for laboratory use. Design variables are described, included desired torque-measuring device characteristics, diaphragm design, pilot valve, the torque-indicating instrument, the capacity range, ability of reversed operation, and double-acting operation. The accuracy is described as satisfactory and effects of other variables are negligible.
Date: March 1944
Creator: Moore, Charles S.; Biermann, Arnold E. & Voss, Fred
Partner: UNT Libraries Government Documents Department
open access

Dilution of Exhaust-Gas Samples From a Multicylinder Engine Equipped With an Exhaust-Gas Collector

Description: Report discusses the results of an investigation to determine the effect of a collector ring on exhaust-gas sampling. The results of tests to determine the percentage by volume of exhaust gas from the collector ring are presented for several engine powers and speeds. The danger of air dilution from the breathing action of the engine is almost entirely eliminated by the use of a collector ring.
Date: February 1945
Creator: Butze, Helmut F.
Partner: UNT Libraries Government Documents Department
open access

Relative Effects of Cylinder-Head and Inlet-Mixture Temperatures Upon Knock Limits of Fuels

Description: Report discusses an investigation into the relation between the effects of cylinder-head temperature and inlet-mixture temperature on the knock limits of fuels. The tests were run at a constant fuel-air ratio and the decrease in cylinder-head temperature required to offset the effect of increasing the inlet-mixture temperature on knock-limited power was determined. The apparatus and testing procedure are described and the effect of changes in cylinder-head temperature on the knock limit of any … more
Date: October 1944
Creator: Sanders, Newell D.; Wear, Jerrold D. & Hensley, Reece V.
Partner: UNT Libraries Government Documents Department
open access

The Knock-Limited Performance of Several Fuels Blended With S-2 Reference Fuel

Description: Report discussing the results of testing conducted to determine the knock-limited performance of fuel blends containing 80 percent of S-2 reference fuel and 20 percent of several exploratory fuels. Butyl acetate, sec-butyl acetate, isopropyl acetate, sec-butyl alcohol, tert-butyl alcohol, isopropyl alcohol, cyclohexanol, methylcyclohexanol, isobutylcarbinol, sec-butylcarbinol, triethyl borate, and dimethylfuran were examined.
Date: November 1944
Creator: Alquist, Henry E.
Partner: UNT Libraries Government Documents Department
open access

An Estimation of the Internal-Cooling Requirements of an Aircraft-Engine Cylinder When Using Oxygen Boost

Description: Report discusses a method developed to estimate the quantities of internal coolants required to prevent overheating of the aircraft cylinder when oxygen boost is applied. The formula and calculations related to inlet-air pressure, added oxygen, added water, added nitrogen, and total fluid weight are detailed.
Date: November 1944
Creator: Evvard, John C. & Moeckel, W. E.
Partner: UNT Libraries Government Documents Department
open access

Tests of Beams Having Webs With Large Circular Lightening Holes

Description: "Strength tests were made on two sets of beams having webs with large circular lightening holes. The main conclusion drawn from the tests is that allowable web stressed derived from pure shear tests and allowable flange stresses derived from compression tests cannot be applied in the design of beams without making corrections for interaction" (p. 1). Pure shear tests and beam tests were performed and the circumstances of failure were investigated.
Date: February 1944
Creator: Levin, L. Ross
Partner: UNT Libraries Government Documents Department
open access

The Fatigue Strengths of Some Wrought Aluminum Alloys

Description: Report presenting an exploration of fatigue stresses of some wrought aluminum alloys, including charts that cover different ranges of stress and number of cycles.
Date: June 1942
Creator: Stickley, G. W.
Partner: UNT Libraries Government Documents Department
open access

Effect of Normal Pressure on the Critical Shear Stress of Curved Sheet

Description: "In order to determine the critical stresses caused by an outward acting pressure on the upper surface of a wing due to the difference in internal and external pressures, torsional tests were made on two curved-sheet specimens subjected to an outward acting normal pressure. Results show that an outward acting normal pressure appreciable raises the critical shear stress for an unstiffened curved sheet; the absolute increase in critical shear stress is slightly greater for a 30 in. rib spacing th… more
Date: January 1943
Creator: Rafel, Norman
Partner: UNT Libraries Government Documents Department
open access

Effects of Fuel-Vapor Loss on Knock-Limited Performance and Inspection Properties of Aviation Fuels

Description: Report discussing the results of testing to discover the effects of fuel-vapor loss on F-3 and F-4 knock-limited performance ratings and inspection properties of two aviation fuels, 28-R and 33-R. The percentage of loss at several temperatures, ability to meet Army-Navy fuel specifications, and antiknock rating change is described.
Date: March 1946
Creator: Barnett, Henry C. & Marsh, Edred T.
Partner: UNT Libraries Government Documents Department
open access

Lead Susceptibility of Several Fuels as Determined in an Air-Cooled Aircraft-Engine Cylinder

Description: "In order to determine the lead susceptibility of several fuels, leaded and unleaded fuels from the same stock were blended and tested in a full-scale air-cooled aircraft-engine cylinder. The fuels were S-4 reference fuel, virgin-base stock, aviation alkylate, neohexane, and blends of 25-percent benzene with 75-percent virgin-base stock and 25-percent toluene with 75-percent virgin-base stock" (p. 1).
Date: February 1946
Creator: Stricker, Edward G. & Hensley, Reece V.
Partner: UNT Libraries Government Documents Department
open access

The Knock-Limited Performance of Fuel Blends Containing Spiropentane, Methylenecyclobutane, Di-Tert-Butyl Ether, Methyl Tert-Butyl Ether, and Triptane

Description: Tests show that at inlet-air temperatures of 250 deg F and 100 deg F the knock-limited performance of the base fuel of blends, leaded with 4 ml TEL per gallon and containing 20 percent spiropentane, was reduced at fuel/air ratios below 0.085. The 20 percent methylenecyclobutane reduced the knock-limited power of the base fuel at fuel/air ratios below 0.112. Di-tert-butyl ether, methyl-tert-butyl ether, and triptane increased the knock-limited power of the base fuel at all fuel/air ratios and at… more
Date: May 1946
Creator: Meyer, Carl L.
Partner: UNT Libraries Government Documents Department
open access

Investigation of Methods of Supporting Single-Thickness Specimens in a Fixture for Determination of Compressive Stress-Strain Curves

Description: "An investigation was made of the methods of supporting single-thickness specimens of aluminum-alloy sheet material in a fixture for determination of compressive stress-strain curves. The specimens were supported in the fixture by rollers, offset-grooved plates, opposite-grooved plates, flat brass plates, or flat wooden plates. The investigation also showed that the compression fixture, the specimen support, and the single-thickness specimens must be accurately made in order to obtain accurate … more
Date: May 1945
Creator: Kotanchik, Joseph N.; Woods, Walter & Weinberger, Robert A.
Partner: UNT Libraries Government Documents Department
open access

Use of Stagnation Temperature in Calculating Rate of Heat Transfer in Aircraft Heat Exchangers

Description: "Theoretical and experimental investigations of the effect of frictional heat on the rate of heat transmission at high fluid velocities are briefly reviewed. On the basis of these investigations, calculations are made which show that the use of the stagnation temperature of the cooling air as the effective temperature for heat transfer in an aircraft heat exchanger is sufficiently accurate" (p. 1).
Date: October 1943
Creator: Wood, George P.
Partner: UNT Libraries Government Documents Department
open access

Flight Tests of a Glider Model Towed by Twin Parallel Towlines

Description: "The stability characteristics of a glider towed by twin parallel towlines have been studied in the NACA free-flight tunnel. A preliminary theoretical analysis of the stability of a glider restrained from yawing was followed by an experimental investigation of the stability of a model towed from fixed tunnel points in such a way as to simulate tow in level flight. The results of the tests confirm the theoretical analysis and indicate that a pilotless, stable, towed-glider system is possible whe… more
Date: April 1943
Creator: Pitkin, Marvin & McKinney, Marion O., Jr.
Partner: UNT Libraries Government Documents Department
open access

Hydrodynamic-stability tests of a model of a flying boat and of a planing surface having a small downward projection (hook) on the planing bottom near the step

Description: Report presenting stability testing of two dynamic models in tank no. 1 in order to investigate the effects of adding a small projection, or hook, on the planing bottom of the forebody near the step of a seaplane. Tests with two different projections had a rather large effect on all of the trim limits and the landing stability.
Date: January 1943
Creator: Benson, James M.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen