Search Results

open access

Standard nomenclature for airspeeds with tables and charts for use in calculation of airspeed

Description: Symbols and definition of various airspeed terms that have been adopted as standard by the NACA subcommittee on aircraft structural design are presented. The equations, charts, and tables required in the evaluation of true airspeed, calibrated airspeed, equivalent airspeed, impact and dynamic pressures, and Mach and Reynolds numbers have been compiled. Tables of the standard atmosphere to an altitude of 65,000 feet and a tentative extension to an altitude of 100,000 feet are given along with th… more
Date: July 17, 1946
Creator: Aiken, William S., Jr.
open access

A simplified theoretical method of determining the characteristics of a lifting rotor in forward flight

Description: Theoretical derived expressions for the flapping, the thrust, the torque, and the profile drag-lift ratio of nonfeathering rotor with hinged, rectangular, linearly twisted blades are given as simple functions of the inflow velocity and the blade pitch. Representative values of the coefficients of each of the terms in these expressions are tabulated for a series of specified values of the tip-speed ratio. Analysis indicates that the tabulated values can be used to calculate, with reasonable accu… more
Date: March 17, 1941
Creator: Bailey, F. J., Jr.
open access

Investigation of the Stability and Control Characteristics of a 1/20-Scale Model of the Consolidated Vultee XB-53 Airplane in the Langley Free-Flight Tunnel

Description: "An investigation of the low-speed, power-off stability and control characteristics of a 1/20-scale model of the Consolidated Vultee XB-53 airplane has been conducted in the Langley free-flight tunnel. In the investigation it was found that with flaps neutral satisfactory flight behavior at low speeds was obtainable with an increase in height of the vertical tail and with the inboard slats opened. In the flap-down slat-open condition the longitudinal stability was satisfactory, but it was impos… more
Date: November 17, 1947
Creator: Bennett, Charles V.
open access

Free-Spinning-Tunnel Tests of a 1/24-Scale Model of the North American XP-86 Airplane

Description: "A spin investigation has been conducted in the Langley 20-foot free-spinning tunnel on a 1/24-scale model of the North American XP-86 airplane. The effects of control settings and movements upon the erect and inverted spin and recovery characteristics of the model were determined for the design gross weight loading. The long-range loading was also investigated and the effects of extending slats and dive flaps were determined" (p. 1).
Date: May 17, 1948
Creator: Berman, Theodore
open access

Control requirements and control parameters for a ram jet with variable-area exhaust nozzle

Description: Report presenting control requirements and parameters for a ram jet with a variable-area exhaust nozzle, which have been analyzed from calculated performance charts covering flight Mach numbers from 0.6 to 3.0 and altitudes from sea level to 30,000 feet. Requirements for maximum efficiency, safe and stable operation, maximum range of thrust at a given flight Mach number, and control of fuel flow are discussed and control parameters are selected.
Date: November 17, 1948
Creator: Boksenbom, Aaron S. & Novik, David
open access

Preliminary Wind-Tunnel Tests of Triangular and Rectangular Wings in Steady Roll at Mach Numbers of 1.62 and 1.92

Description: Report presenting the damping-in-roll coefficients for a series of thin triangular plan-form wings and two rectangular wings in the 9-inch supersonic wind tunnel. The damping in roll of the rectangular wings was very close to what was predicted by linear theory, but the triangular wings gave results approximately 10 percent below that predicted when the wing leading edges were well ahead of or behind the Mach cone.
Date: February 17, 1949
Creator: Brown, Clinton E. & Heinke, Harry S., Jr.
open access

Spectra and diffusion in a round turbulent jet

Description: "In a round turbulent jet at room temperature, measurement of the shear correlation coefficient as a function of frequency (through band-pass filters) has given a rather direct verification of Kolmogoroff's local-isotropy hypothesis. One-dimensional power spectra of velocity and temperature fluctuations, measured in unheated and heated jets, respectively, have been contrasted. Under the same conditions, the two corresponding transverse correlation functions have been measured and compared" (p. … more
Date: August 17, 1949
Creator: Corrsin, Stanley & Uberoi, Mahinder S.
open access

Qualitative Measurements of Relative Flap Effectiveness at Transonic Speeds on a Series of Five Thin Airfoils With 25-Percent-Chord Flaps and Various Amounts of Sweepback

Description: Report presenting testing on a series of five flat plate models of aspect ratio 2.0 with 25-percent-mean-aerodynamic-chord flaps at a range of Mach numbers in order to investigate the effect of sweepback on flap effectiveness.
Date: May 17, 1948
Creator: Crane, Harold L. & McLaughlin, Milton D.
open access

Performance of Compressor of Xj-41-v Turbojet Engine, 3, Compressor Static-Pressure Rise at Equivalent Compressor Speeds of 5000, 7000, 8000, and 9000 RPM

Description: "At the request of the Air Materiel Command, Army Air Forces, an investigation is being conducted at the NACA Cleveland laboratory to determine the performance characteristics of the XJ-41-V turbojet-engine compressor. The static-pressure variation in the direction of flow through the compressor was presented in reference 1 for an equivalent speed of 8000 rpm. An analysis of these pressure indicated that the maximum-flow limitation of the compressor was caused by separation, which reduced the e… more
Date: July 17, 1947
Creator: Creagh, John W. R. & Ginsburg, Ambrose
open access

Resonance Absorption in Lumps and Mixtures

Description: The resonance absorption of a lump is described in terms of three components. Calculations of resonance absorption are carried out using the model for the resonance spectrum of uranium recently derived; calculations are also made with variations of this model which involve local fluctuations in level strengths. For metal and oxide lumps the agreement with observation is satisfactory. For dilute mixtures, whose resonance activation was measured by Mitchell, computed values fall 20% to 30% above … more
Date: April 17, 1944
Creator: Dancoff, Sidney M., 1913-1951 & Gingburg, M.
open access

Wind-tunnel investigation of horizontal tails 3: unswept and 35 degrees swept-back plan forms of aspect ratio 6

Description: Report presenting the results of a wind-tunnel investigation of the low-speed aerodynamic characteristics of two semispan horizontal tails with unswept and 35 degree sweptback plan forms. Test results are provided for models with and without standard roughness on their leading edges and with sealed and unsealed radius-nose elevators. Results regarding effectiveness and hinge-moment parameters, static longitudinal stability, effect of standard roughness, and effect of removing the elevator nose … more
Date: December 17, 1948
Creator: Dods, Jules B., Jr.
open access

NACA Investigation of a Jet-Propulsion System Applicable to Flight

Description: "Following a brief history of the NACA investigation of jet propulsion, a discussion is given of the general investigation and analysis leading to the construction of the jet-propulsion ground-test mock-up. The results of burning experiments and of test measurements designed to allow quantitative flight performance predictions of the system are presented and correlated with calculations. These calculations are then used to determine the performance of the system on the ground and in the air at … more
Date: September 17, 1943
Creator: Ellis, Macon C., Jr. & Brown, Clinton E.
open access

Technical Department report on Production Test No. 313-58-M: Recovery of lead dipped slugs

Description: A number of slugs have been dipped in lead, then Al-Si and canned. Laboratory experiments showed that the can and outer bonding layers could be removed by the standard caustic-nitrate treatment. The alloy layer was removed from several slugs by hot nitric acid without use of hydrofluoric acid. It was desired to extend the method to the plant process and to clean accumulated lead dipped pieces. Lead dipped slugs may be cleaned by the regular recovery process with a weight loss of about 0.03 lbs.… more
Date: January 17, 1945
Creator: Eubank, L. D.
open access

Use of source distributions for evaluating theoretical aerodynamics of thin finite wings at supersonic speeds

Description: From Summary: "A series of publications on the source-distribution methods for evaluating the aerodynamics of thin wings at supersonic speeds is summarized, extended, and unified. Included in the first part are the deviations of: (a) the linearized partial-differential equation for unsteady flow at a substantially constant Mach number. b) The source-distribution solution for the perturbation-velocity potential that satisfies the boundary conditions of tangential flow at the surface and in the p… more
Date: June 17, 1949
Creator: Evvard, John C.
open access

Performance of Compressor XJ-41-V Turbojet Engine 1 - Preliminary Investigation at Equivalent Compressor Speed of 8000 RPM

Description: From Summary: "At the request of the Air Material Command, Arm Air Forces, an investigation was conducted at the NACA Cleveland laboratory to determine the performance characteristics of the XJ-41-V turbojet-engine compressor. The complete compressor was mounted on a collecting chamber having an annular air-flow passage simulating the burner annulus of the engine and was driven by an electric motor. The compressor was extensively instrumented to determine the overall performance of the compress… more
Date: January 17, 1947
Creator: Ginsburg, Ambrose & Creagh, John W. R.
open access

Lateral stability and control characteristics of an airplane model having 42.8 degree sweptback circular-arc wing with aspect ratio 4.00, taper ratio 0.50, and sweptback tail surfaces

Description: Report presenting testing in the 300 mph 7- by 10-foot tunnel of an airplane model with a 42.8 degree sweptback wing with an aspect ratio 4.00, taper ratio 0.50, a 42.8 degree sweptback horizontal tail, and a 40.3 degree sweptback vertical tail to determine the low-speed lateral stability and control characteristics. Some changes made to improve the aerodynamic characteristics included lowering the wing, incorporating a smaller-fineness-ratio fuselage, and increasing the vertical tail size. Res… more
Date: October 17, 1947
Creator: Goodson, Kenneth W. & Comisarow, Paul
Back to Top of Screen