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The Supersonic Axial-Flow Compressor

Description: "An investigation has been made to explore the possibilities of axial-flow compressors operating with supersonic velocities into the blade rows. Preliminary calculations showed that very high pressure ratios across a stage, together with somewhat increased mass flows, were apparently possible with compressors which decelerated air through the speed of sound in their blading. The first phase of the investigation was the development of efficient supersonic diffusers to decelerate air through the speed of sound" (p. 473).
Date: March 8, 1946
Creator: Kantrowitz, Arthur
Partner: UNT Libraries Government Documents Department
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Extension of Useful Operating Range of Axial-Flow Compressors by Use of Adjustable Stator Blades

Description: "A theory has been developed for resetting the blade angles of an axial-flow compressor in order to improve the performance at speeds and flows other than the design and thus extend the useful operating range of the compressor. The theory is readily applicable to the resetting of both rotor and stator blades or to the resetting of only the stator blades and is based on adjustment of the blade angles to obtain lift coefficients at which the blades will operate efficiently. Calculations were made for resetting the stator blades of the NACA eight-stage axial-flow compressor for 75 percent of design speed and a series of load coefficients ranging from 0.28 to 0.70 with rotor blades left at the design setting" (p. 425).
Date: December 29, 1944
Creator: Sinnette, John T., Jr. & Voss, William J.
Partner: UNT Libraries Government Documents Department
open access

On the Flow of a Compressible Fluid by the Hodography Method 1: Unification and Extension of Present-Day Results

Description: Report presenting elementary basic solutions of the equations of motion of a compressible fluid in the hodograph variables are developed and used to provide a basis for comparison in the form of velocity correction formulas, of corresponding compressible and incompressible flows.
Date: March 1944
Creator: Garrick, I. E. & Kaplan, Carl
Partner: UNT Libraries Government Documents Department
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Performance of an exhaust-gas "blowdown" turbine on a nine-cylinder radial engine

Description: Report presenting tests on an exhaust-gas turbine with four separate nozzle boxes each covering a 90 degree arc of the nozzle diaphragm and each connected to a pair of adjacent cylinders in a Pratt & Whitney R-1340-12 nine-cylinder radial engine. Results regarding the power output of the engine and turbine, effect of the turbine on engine power, turbine power output and speed characteristics, mean turbine efficiency, effect of the blowdown turbine on exhaust-gas temperature, and condition of the blowdown turbine after tests are provided.
Date: December 1944
Creator: Turner, L. Richard & Desmon, Leland G.
Partner: UNT Libraries Government Documents Department
open access

Notes on the Effect of Surface Distortions on the Drag and Critical Mach Number of Airfoils

Description: "The effect of two-dimensional bumps and surface waviness on the pressure distribution over airfoils is considered. It is shown that the results of the analysis may be useful in evaluating the effects of accidental or intended surface distortions on the drag and critical Mach number of airfoils" (p. 1).
Date: September 1943
Creator: Allen, H. Julian
Partner: UNT Libraries Government Documents Department
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On the Flow of a Compressible Fluid by the Hodography Method 2: Fundamental Set of Particular Flow Solutions of the Chaplygin Differential Equation

Description: Report presenting the utilization of the differential equation of Chaplygin's jet problem to give a systematic development of particular solutions of the hodograph flow equations, which extends the treatment of Chaplygin into the supersonic range and completes the set of particular solutions. The solutions serve to place on a reasonable basis the use of velocity correction formulas for the comparison of incompressible and compressible flows.
Date: November 1944
Creator: Kaplan, Carl
Partner: UNT Libraries Government Documents Department
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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 analyses 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 various speeds and altitudes under various burning conditions. The application of the system to an experimental airplane is described and some performance predictions for this airplane are made" (p. 1).
Date: April 1944
Creator: Brown, Clinton E.
Partner: UNT Libraries Government Documents Department
open access

The Propeller and Cooling-Air-Flow Characteristics of a Twin-Engine Airplane Model Equipped With NACA D(Sub S)-Type Cowlings and With Propellers of NACA 16-Series Airfoil Sections

Description: Report presenting an investigation in the 19-foot pressure tunnel to determine the nacelle drag, the cowling-air flow, and the propeller characteristics of a model of a high-performance military airplane. The model is fitted with NACA D(sub S)-type engine cowlings and with propellers embodying NACA 16-series airfoil sections. Results regarding the propeller characteristics, drag and cowling-air flow with the propeller removed, the effect of propeller on flow through cowling, and the influence of cooling requirements on airplane performance are provided.
Date: September 1944
Creator: McHugh, James G. & Pepper, Edward
Partner: UNT Libraries Government Documents Department
open access

Experiments on Drag of Revolving Disks, Cylinders and Streamline Rods at High Speeds

Description: Report presenting an experimental investigation concerned primarily with the extension of test data on the drag of revolving disks, cylinders, and streamline rods to high Mach numbers and Reynolds numbers. The tests generally confirm earlier theories and add in some new results. One of the primary findings of interest is that skin friction does not depend on Mach number.
Date: June 1944
Creator: Theodorsen, Theodore & Regier, Arthur
Partner: UNT Libraries Government Documents Department
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Determination of General Relations for the Behavior of Turbulent Boundary Layers

Description: Report presenting an analysis of data for turbulent boundary layers along wings and bodies of various shapes in order to determine the fundamental variables that control the development of turbulent boundary layers. Results indicate that the type of velocity distribution in the boundary layer could be expressed in terms of a single parameter.
Date: July 1943
Creator: von Doenhoff, Albert E. & Tetervin, Neal
Partner: UNT Libraries Government Documents Department
open access

NACA Mach number indicator for use in high-speed tunnels

Description: Report presenting a description of a device for indicating stream Mach number in a high-speed tunnel. It consists of a mechanism for determining the pressure ratio that Mach number is a function of. The instrument is in service in the 8-foot high-speed tunnel and its accuracy has been found adequate for wind-tunnel requirements.
Date: July 1943
Creator: Smith, Norman F.
Partner: UNT Libraries Government Documents Department
open access

The development and application of high-critical-speed nose inlets

Description: From Summary: "An analysis of the nose-inlet shapes developed in previous investigations to represent the optimum from the standpoint of critical speed has shown that marked similarity exists between the nondimensional profiles of inlets which have widely different proportions and critical speeds. With the nondimensional similarity of such profiles established, the large differences in the critical speeds of these nose inlets must be a function of their proportions. An investigation was undertaken in the Langley 8-foot high-speed tunnel to establish the effects of nose-inlet proportions on critical Mach number and to develop a rational method for the design of high-critical-speed nose inlets to meet desired requirements."
Date: July 1945
Creator: Baals, Donald D.; Smith, Norman F. & Wright, John B.
Partner: UNT Libraries Government Documents Department
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Profile-Drag Coefficients of Conventional and Low-Drag Airfoils as Obtained in Flight

Description: "The results of flight investigations of the profile drag of several carefully finished conventional and low-drag airfoils are presented. The results indicated that in all cases lower profile-drag coefficients were obtained with the low-drag than with the conventional airfoils over the range of lift coefficient tested and that, for comparable conditions of lift coefficient and Reynolds number, the low-drag airfoils may have profile-drag coefficients which are at least 27 percent lower than the profile-drag coefficients of the conventional airfoils" (p.1).
Date: May 1944
Creator: Zalovcik, John A.
Partner: UNT Libraries Government Documents Department
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A Concise Theoretical Method for Profile-Drag Calculation; Advance Report

Description: In this report a method is presented for the calculation of the profile drag of airfoil sections. The method requlres only a knowledge of the theoretical velocity distribution and can be applied readily once this dlstribution is ascertained. Comparison of calculated and experimental drag characteristics for several airfoils shows a satisfactory agreement. Sample calculatlons are included.
Date: February 1944
Creator: Nitzberg, Gerald E.
Partner: UNT Libraries Government Documents Department
open access

Experimental verification of a simplified vee-tail theory and analysis of available data on complete models with vee tails

Description: Report presenting an analysis of available data on vee-tail surfaces. The analysis indicated that a vee tail designed to provide values of stability and control parameters equal to those provided by a conventional tail would probably provide no reduction in area unless the conventional vertical tail is in a bad canopy wake or unless the vee tail has a higher effective aspect ratio than the conventional vertical and horizontal tails.
Date: January 1945
Creator: Purser, Paul E. & Campbell, John P.
Partner: UNT Libraries Government Documents Department
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Flight tests of an all-movable vertical tail on the Fairchild XR2K-1 airplane

Description: Report presenting flight tests of an all-movable vertical tail of reduced area of the Fairchild XR2K-1 airplane. Results are in agreement with previously obtained data on a larger all-movable tail. Results regarding rudder effectiveness, directional stability, rudder-free lateral motion, rudder hinge moments, and areas of future research are provided.
Date: June 1943
Creator: Kleckner, Harold F.
Partner: UNT Libraries Government Documents Department
open access

Effect of a Trailing-Edge Extension on the Characteristics of a Propeller Section

Description: Report presenting a convenient technical method to evaluate changes in the airfoil characteristics resulting from an extension of the chord at the trailing edge of a propeller blade section. The method determines the change in the angle of zero lift, the ideal angle of attack, and the difference in these angles as a function of the angle and length of the trailing-edge extension.
Date: September 1944
Creator: Theodorsen, Theodore & Stickle, George W.
Partner: UNT Libraries Government Documents Department
open access

Collection of Balanced-Aileron Test Data

Description: "Test data of balanced ailerons have been collected from NACA and British sources. These data, which are presented in the form of charts, are grouped as A - ailerons with Frise balances, B - ailerons with blunt-nose balances, C - ailerons with internal balances, D - ailerons with contour modifications, and E - ailerons with tabs. Results of flight tests and of wind-tunnel tests in both two- and three-dimensional flow are presented but no correlation nor resume of the data has been included" (p. 1).
Date: January 1944
Creator: Rogallo, F. M.
Partner: UNT Libraries Government Documents Department
open access

Estimation of Pressures on Cockpit Canopies, Gun Turrets, Blisters, and Similar Protuberances

Description: Report presenting methods for estimating pressure distributions over protuberances such as cockpit canopies, gun turrets, blisters, scoops, and sighting domes. The methods are applied to the estimation of the pressure distributions over spherical segment and faired gun turrets and over the protuberances on the Brewster SB2A-1 airplane. The effects of compressibility, interference, and flow separation are discussed.
Date: May 1944
Creator: Wright, Ray H.
Partner: UNT Libraries Government Documents Department
open access

High-speed drag tests of several fuselage shapes in combination with a wing

Description: Drag testing was conducted in the high-speed wind tunnel of 23 conditions combining six streamline shapes and three conventional cowling-fuselage bodies. All of the models were tested in combination with a wing in order to include wing-fuselage interference effects. The critical speeds of combinations tested were, in general, determined by the wing-fuselage juncture.
Date: August 1940
Creator: Draley, Eugene C.
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of a High-Critical-Speed Fuselage Scoop Including the Effects of Boundary Layer

Description: Report presenting a large air scoop designed for high critical speed, which has been tested in the 8-foot high-speed tunnel on the fuselage of a scale fighter-type airplane. The effects of boundary layer on scoop characteristics were found to be important at all inlet-velocity ratios. Results regarding the boundary-layer surveys, characteristics of original scoop installation, and characteristics of scoop with boundary-layer passage are provided.
Date: February 1945
Creator: Smith, Norman F. & Baals, Donald D.
Partner: UNT Libraries Government Documents Department
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Comparison of fixed-stabilizer, adjustable- stabilizer and all-movable horizontal tails

Description: Report presenting an analysis to compare longitudinal stability and control characteristics obtained with a conventional fixed-stabilizer, an adjustable-stabilizer, and an all-movable horizontal tail. The tail-area requirements, control forces required in the critical landing condition, static margin, control-force gradients in a dive recovery, and elevator-free stability are investigated.
Date: October 1945
Creator: Harmon, Sidney M.
Partner: UNT Libraries Government Documents Department
open access

Wind Tunnel Tests of a Submerged-Engine Fuselage Design

Description: Report presenting tests conducted in the 8-foot high-speed wind tunnel of a scale model pursuit-type fuselage with practicable internal duct arrangement designed to meet all of the air requirements of a 1000-horsepower radial engine submerged at the maximum section. The results showed that the required internal flow can be obtained with negligible ducting losses provided that basic principles are observed in designing the air passages.
Date: October 1940
Creator: Becker, John V. & Baals, Donald D.
Partner: UNT Libraries Government Documents Department
open access

High-Speed Wind-Tunnel Tests of Gun Openings in the Nose of the Fuselage of a 1/4-Scale Model

Description: "In connection with recent tests of a 1/4-scale model pursuit airplane in the NACA 8-foot high-speed tunnel, gun openings having low drag were developed for installation in the nose of the fuselage. The increase in the fuselage-drag coefficient for the final form of openings was 0.0132 at a Mach number of 0.69 and at an angle of attack of 0 degrees. The corresponding drag coefficient based on the wing area was about 0.0005. The critical speed of the airplane was not affected by the gun openings" (p. 1).
Date: July 1942
Creator: Fedziuk, Henry A.
Partner: UNT Libraries Government Documents Department
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