Technical Report Archive and Image Library (TRAIL) - 1,035 Matching Results

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Aerodynamic Characteristics of Three Deep-Stepped Planing-Tail Flying-Boat Hulls

Description: An investigation was made in the Langley 300 MPH 7- by 10-foot tunnel to determine the aerodynamic characteristics of three deep-stepped planing-tail flying-boat hulls differing only in the amount of step fairing. The hulls were derived by increasing the unfaired step depth of a planing-tail hull of a previous aerodynamic investigation to a depth about 92 percent of the hull beam. Tests were also made on a transverse-stepped hull with an extended afterbody for the purpose of comparison and in order to extend and verify the results of a previous investigation. The investigation indicated that the extended afterbody hull had a minimum drag coefficient about the same as a conventional hull, 0.0066, and an angle-of-attack range for minimum drag coefficient of 0.0057 which was 14 percent less than the transverse stepped hull with extended afterbody; the hulls with step fairing had up to 44 percent less minimum drag coefficient than the transverse-stepped hull, or slightly more drag than a streamlined body having approximately the same length and volume. Longitudinal and lateral instability varied little with step fairing and was about the same as a conventional hull.
Date: March 13, 1947
Creator: Riebe, John M. & Naeseth, Rodger L.
Partner: UNT Libraries Government Documents Department

The aerodynamic characteristics throughout the subsonic speed range of a thin, sharp-edged horizontal tail of aspect ratio 4 equipped with a constant-chord elevator

Description: From Introduction: "Recent investigations have indicated several wing plan forms, wing sections, and wing-body-tail combinations suitable for flight at supersonic speeds. One such lifting surface, a thin, sharp-edged without sweep of aspect ratio 4 and taper ratio 0.5, has been the subject of an investigation in the Ames 12-foot pressure wind tunnel. The aim of the investigation was to determine the aerodynamic characteristics of such a wing plan form throughout the range of subsonic Mach numbers up to 0.94."
Date: June 30, 1949
Creator: Bandettini, Angelo & Reed, Verlin D
Partner: UNT Libraries Government Documents Department

Aerodynamic study of a wing-fuselage combination employing a wing swept back 63 degrees : characteristics at a Mach number of 1.53 including effect of small variations of sweep

Description: Measured values of lift, drag, and pitching moment at a Mach number of 1.53 and Reynolds numbers of 0.31, 0.62, and 0.84 million are presented for a wing-fuselage combination having a wing leading-edge sweep angle of 63 degrees, an aspect ratio of 3.42, a taper ratio of 0.25, and an NACA 64A006 section in the stream direction. Data are also presented for sweep angles of 57.0 degrees, 60.4 degrees, 67.0 degrees, and 69.9 degrees. The experimentally determined characteristics were less favorable than indicated by the linear theory but the experimental and theoretical trends with sweep were in good agreement. Boundary-layer-flow tests showed that laminar boundary-layer separation was the primary cause of the differences between experiment and theory.
Date: January 26, 1949
Creator: Madden, Robert T
Partner: UNT Libraries Government Documents Department

Aerodynamic study of a wing-fuselage combination employing a wing swept back 63 degrees : characteristics for symmetrical wing sections at high subsonic and moderate supersonic Mach numbers

Description: From Summary: "Results of wind-tunnel tests are presented for a wing with the leading edge swept back 63^o and of symmetrical section in combination with a body at Mach numbers from 0.5 to 0.95 and from 1.09 to 1.51."
Date: July 7, 1949
Creator: Mas, Newton A
Partner: UNT Libraries Government Documents Department

Air-Stream Surveys in the Vicinity of the Tail of a 1/8.33-Scale Powered Model of the Republic XF-12 Airplane

Description: The XF-12 airplane was designed by Republic Aviation Corporation to provide the Army Air Forces with a high performance, photo reconnaissance aircraft. A series of air-stream surveys were made n the vicinity of the empennage of a 1/8.33-scale powered model of the XF-12 airplane in the Langley 19-foot pressure tunnel. Surveys of the vortical-tail region were made through a range of yaw angles of plus or minus 20 degrees at a high and low angle of attack. The horizontal-tail surveys were made over a fairly wide range of angles of attack at zero degrees yaw. Several power and flap conditions were investigated. The results are presented in the form a dynamic pressure ratios, sidewash angles, and downwash angles plotted against vertical distance from the fuselage center line. The results of the investigation indicate that a vertical tail located in a conventional position would be in a field of flow where the dynamic pressure ratios at the horizontal tail to be increased; for equal lift coefficients, the effect of power or flap deflection on the direction of flow at any particular point in the region of the horizontal tail is small.
Date: April 8, 1947
Creator: Foster, Gerald V.
Partner: UNT Libraries Government Documents Department

Altitude cooling investigation of the R-2800-21 engine in the P-47G airplane II : investigation of the engine & airplane variables affecting the cylinder temperature distribution

Description: The data obtained from cooling tests of an R-2800-21 engine installed in a p-47G airplane were studied to determine which engine and airplane operation variables were mainly responsible for the extremely uneven temperature distribution among the 18 engine cylinders obtained at the medium and high engine-power conditions. The tests consisted of flights at altitudes from 5000 to 35,000 feet for the normal range of engine and airplane operation. The results of the study showed that a flow condition in the induction system associated with the wide-open throttle position, which affected either the fuel air or charge distribution, was primarily responsible for the uneven temperature distribution. For the range of fuel-air ratios tested (0.080 to 0.102), the temperature distribution remained essentially unchanged. The individual effects of thrust-axis inclination, cowl-flap opening, and quantity of auxiliary air were found to be secondary in importance. At low angles of throttle opening, engine speed was found to have little effect on the temperature pattern.
Date: October 9, 1946
Creator: Pesman, Gerard J & Kaufman, Samuel J
Partner: UNT Libraries Government Documents Department

Altitude cooling investigation of the R-2800-21 engine in the P-47g airplane III : individual-cylinder temperature reduction by means of intake-pipe throttle and by coolant injection

Description: Flight tests were conducted on a R-2800-21 engine in the P-47G airplane to determine the effect on the wall temperatures of cylinder 10 of throttling the charge in the intake pipe and of injecting a water-ethanol coolant into the intake pipe. Cylinder 10 was chosen for this investigation because it runs abnormally hot (head temperatures of the order of 45 F higher than those of the next hottest cylinder) at the medium and high-power conditions. Tests with interchanged cylinders showed that the excessive temperatures of cylinder 10 were inherent in the cylinder location and were not due to the mechanical condition of the cylinder assembly. Throttling the charge in the intake pipe is a simpler method than coolant injection into the intake pipe particularly when only one cylinder is considerably hotter than any other. Coolant injection into the individual cylinders is a more efficient method than throttling in the intake pipe and is warranted when several cylinders are to be cooled or when parts of the complex equipment required are already available.
Date: October 9, 1946
Creator: Bell, E Barton; Valerino, Michael F & Manganiello, Eugene J
Partner: UNT Libraries Government Documents Department