Preliminary Results Obtained from Flight Test of a Rocket Model Having the Tail Only of the Grumman XF10F Airplane Configuration, TED No. NACA DE 354 (open access)

Preliminary Results Obtained from Flight Test of a Rocket Model Having the Tail Only of the Grumman XF10F Airplane Configuration, TED No. NACA DE 354

"A flight test was made to determine the servoplane effectiveness and stability characteristics of the free-floating horizontal stabilizer to be used on the XF10F airplane. The results of this test indicate that servoplane effectiveness is practically constant through the speed range up to a Mach number of 1.15, and the stabilizer static stability is satisfactory. A loss of damping occurs over a narrow Mach number range near M = 1.0, resulting in dynamic instability of the stabilizer in this narrow range" (p. 1).
Date: 1950?
Creator: Gardner, William N. & Edmondson, James L.
System: The UNT Digital Library
Theoretical and analog studies of the effects of nonlinear stability derivatives on the longitudinal motions of an aircraft in response to step control deflections and to the influence of proportional automatic control (open access)

Theoretical and analog studies of the effects of nonlinear stability derivatives on the longitudinal motions of an aircraft in response to step control deflections and to the influence of proportional automatic control

Through theoretical and analog results the effects of two nonlinear stability derivatives on the longitudinal motions of an aircraft have been investigated. Nonlinear functions of pitching-moment and lift coefficients with angle of attack were considered. Analog results of aircraft motions in response to step elevator deflections and to the action of the proportional control systems are presented. The occurrence of continuous hunting oscillations was predicted and demonstrated for the attitude stabilization system with proportional control for certain nonlinear pitching-moment variations and autopilot adjustments.
Date: December 29, 1950
Creator: Curfman, Howard J., Jr.
System: The UNT Digital Library
Propeller Flight Investigation to Determine the Effects of Blade Loading (open access)

Propeller Flight Investigation to Determine the Effects of Blade Loading

Note presenting a flight investigation of a three-blade propeller in climb and at high speed to determine the effects of blade power loading. Increasing the blade power coefficient from 0.06 to 0.09 was found to increase the efficiency approximately 8 percent at an airplane Mach number of 0.7 and a propeller-tip Mach number of 1.13. In climb, an increase in power loading over the range of blade power coefficients investigated was shown to reduce efficiency, as a consequence of increased induced drag losses.
Date: January 1950
Creator: Hammack, Jerome B. & Vogeley, A. W.
System: The UNT Digital Library
The effects of compressibility on the pressures on a body of revolution and on the aerodynamic characteristics of a wing-nacelle combination consisting of the body of revolution mounted on a swept-back wing (open access)

The effects of compressibility on the pressures on a body of revolution and on the aerodynamic characteristics of a wing-nacelle combination consisting of the body of revolution mounted on a swept-back wing

Memorandum presenting an investigation of the effects of compressibility on the forces, pitching moments, and surface pressures on a wing-nacelle combination. The leading edge of the wing was swept back 37.25 degrees and the nacelle was a body of revolution with a fineness ratio of 6.5. The effects of compressibility on the surface pressures and on the drag of a body of revolution similar to the nacelle were also determined.
Date: July 26, 1950
Creator: Boltz, Frederick W. & Beam, Benjamin H.
System: The UNT Digital Library
Time-dependent downwash at the tail and the pitching moment due to normal acceleration at supersonic speeds (open access)

Time-dependent downwash at the tail and the pitching moment due to normal acceleration at supersonic speeds

Report presenting an analysis of the time-dependent downwash behind a wing in a supersonic stream when the angle of attack varies linearly with time. The result is applied to the calculation of the contribution of the horizontal tail to the pitching moment and lift due to normal acceleration of the airplane. Results regarding downwash charts and some limitations on the results are provided.
Date: February 1950
Creator: Ribner, Herbert S.
System: The UNT Digital Library
Analysis of effect of variations in primary variables on time constant and turbine-inlet-temperature overshoot of turbojet engine (open access)

Analysis of effect of variations in primary variables on time constant and turbine-inlet-temperature overshoot of turbojet engine

From Introduction: "The design of turbojet-engine control systems is intimately related to the dynamic characteristics of the engine and has advanced to the stage where theoretically correct control constants can be determined for fixed dynamic properties (references 1 and 2). The use of the thermodynamic equations presupposes that the engine processes are quansi-static. Such an assumption is shown to be valid for a turbojet engine in references 3 and 4.
Date: September 1950
Creator: Heidmann, Marcus F.
System: The UNT Digital Library
Theoretical investigation and application of transonic similarity law for two dimensional flow (open access)

Theoretical investigation and application of transonic similarity law for two dimensional flow

Report presenting an investigation of the use of the transonic similarity law for two-dimensional flow by an iteration procedure. The results indicated that potential can be expressed as a power series in a single parameter that depends on Mach number, thickness ratio, and ratio of specific heats.
Date: October 1950
Creator: Perl, William & Klein, Milton M.
System: The UNT Digital Library
Application of the Laplace Transformation to the Solution of the Lateral and Longitudinal Stability Equations (open access)

Application of the Laplace Transformation to the Solution of the Lateral and Longitudinal Stability Equations

Note presenting the application of the Laplace transformation to the solution of the lateral and longitudinal stability equations. The expressions for the time history of the motion in response to a sinusoidal control motion are derived for the general case in which all initial measurements are assumed different from zero.
Date: January 1950
Creator: Mokrzycki, G. A.
System: The UNT Digital Library
Longitudinal Stability and Control Characteristics at High Subsonic Speeds of Two Models of a Transonic Research Airplane With Wings and Horizontal Tails of Aspect Ratios 4.2 and 2 (open access)

Longitudinal Stability and Control Characteristics at High Subsonic Speeds of Two Models of a Transonic Research Airplane With Wings and Horizontal Tails of Aspect Ratios 4.2 and 2

Report discussing an investigation of two transonic research airplane models at a range of Mach numbers and Reynolds numbers. The main difference between the models was the aspect ratio of the horizontal tail. Results regarding the stability, control, incremental horizontal-tail characteristics, downwash, horizontal-tail load, stability factors, and a tailless configuration are provided.
Date: September 29, 1950
Creator: Luoma, Arvo A. & Wright, John B.
System: The UNT Digital Library
Summary of methods for calculating dynamic lateral stability and response and for estimating aerodynamic stability derivatives (open access)

Summary of methods for calculating dynamic lateral stability and response and for estimating aerodynamic stability derivatives

"A summary of methods for making dynamic lateral stability and response calculations and for estimating the aerodynamic stability derivatives required for use in these calculations is presented. The processes of performing calculations of the time histories of lateral motions, of the period and damping of these motions, and of the lateral stability boundaries are presented as a series of simple straightforward steps. Existing methods for estimating the stability derivatives are summarized and, in some cases, simple new empirical formulas are presented. Detailed estimation methods are presented for low-subsonic-speed conditions but only a brief discussion and a list of references are given for transonic and supersonic speed conditions" (p. 1).
Date: December 13, 1950
Creator: Campbell, John P. & McKinney, Marion O.
System: The UNT Digital Library