This system will be undergoing maintenance Tuesday, December 6 from 9AM to 12PM CST.

  You limited your search to:

  Partner: UNT Libraries Government Documents Department
 Decade: 1920-1929
 Year: 1925
 Collection: Technical Report Archive and Image Library
Accelerations in flight

Accelerations in flight

Date: 1925
Creator: Doolittle, J H
Description: This work on accelerometry was done at McCook Field for the purpose of continuing the work done by other investigators and obtaining the accelerations which occur when a high-speed pursuit airplane is subjected to the more common maneuvers. The accelerations obtained in suddenly pulling out of a dive with well-balanced elevators are shown to be within 3 or 4 per cent of the theoretically possible accelerations. The maximum acceleration which a pilot can withstand depends upon the length of time the acceleration is continued. It is shown that he experiences no difficulty under the instantaneous accelerations as high as 7.8 G., but when under accelerations in excess of 4.5 G., continued for several seconds, he quickly loses his faculties.
Contributing Partner: UNT Libraries Government Documents Department
Aerodynamic characteristics of aircraft with reference to their use

Aerodynamic characteristics of aircraft with reference to their use

Date: 1925
Creator: Panetti, M
Description: Economic and design characteristics are examined in the design of airplanes and airships.
Contributing Partner: UNT Libraries Government Documents Department
Aerodynamic characteristics of airfoils at high speeds

Aerodynamic characteristics of airfoils at high speeds

Date: 1925~
Creator: Briggs, L. J.; Hull, G. F. & Dryden, H. L.
Description: This report deals with an experimental investigation of the aerodynamical characteristics of airfoils at high speeds. Lift, drag, and center of pressure measurements were made on six airfoils of the type used by the air service in propeller design, at speeds ranging from 550 to 1,000 feet per second. The results show a definite limit to the speed at which airfoils may efficiently be used to produce lift, the lift coefficient decreasing and the drag coefficient increasing as the speed approaches the speed of sound. The change in lift coefficient is large for thick airfoil sections (camber ratio 0.14 to 0.20) and for high angles of attack. The change is not marked for thin sections (camber ratio 0.10) at low angles of attack, for the speed range employed. At high speeds the center of pressure moves back toward the trailing edge of the airfoil as the speed increases. The results indicate that the use of tip speeds approaching the speed of sound for propellers of customary design involves a serious loss in efficiency.
Contributing Partner: UNT Libraries Government Documents Department
Aeronautic instruments. Section I : general classification of instruments and problems including bibliography

Aeronautic instruments. Section I : general classification of instruments and problems including bibliography

Date: 1925
Creator: Hersey, Mayo D.
Description: This report is intended as a technical introduction to the series of reports on aeronautic instruments. It presents a discussion of those subjects which are common to all instruments. First, a general classification is given, embracing all types of instruments used in aeronautics. Finally, a classification is given of the various problems confronted by the instrument expert and investigator. In this way the following groups of problems are brought up for consideration: problems of mechanical design, human factor, manufacturing problems, supply and selection of instruments, problems concerning the technique of testing, problems of installation, problems concerning the use of instruments, problems of maintenance, and physical research problems. This enumeration of problems which are common to instruments in general serves to indicate the different points of view which should be kept in mind in approaching the study of any particular instrument.
Contributing Partner: UNT Libraries Government Documents Department
Air flow investigation for location of angle of attack head on a JN4h airplane

Air flow investigation for location of angle of attack head on a JN4h airplane

Date: August 1925
Creator: Freeman, R G
Description: The technical staff of the NACA at Langley Field, has made a series of free flight tests with a JN4h airplane in order to find the best place for an instrument for measuring the angle of attack. A "neutral zone" was found where the air remains either at rest relative to the undisturbed air beyond the influence of the airplane, or is set in motion parallel to the motion of the airplane. This zone is about midway between the two wings and slightly in front of, or at the vertical plane through the leading edges of the wings but the exact position as well as the outlines of the zone varies considerably as the conditions of flight change.
Contributing Partner: UNT Libraries Government Documents Department
Air forces on airfoils moving faster than sound

Air forces on airfoils moving faster than sound

Date: June 1925
Creator: Ackeret, J
Description: We are undertaking the task of computing the air forces on a slightly cambered airfoil in the absence of friction and with an infinite aspect ratio. We also assume in advance that the leading edge is very sharp and that its tangent lies in the direction of motion.
Contributing Partner: UNT Libraries Government Documents Department
Aircraft engine design

Aircraft engine design

Date: January 1, 1925
Creator: Wilson, E E
Description: None
Contributing Partner: UNT Libraries Government Documents Department
Airplane parachutes

Airplane parachutes

Date: August 1925
Creator: Mazer,
Description: The "Bulletin Technique", of March, 1919, gave the results of tests and studies made up to that date in connection with airplane parachutes. This work has been continued.
Contributing Partner: UNT Libraries Government Documents Department
Alloys similar to duralumin made in other countries than Germany

Alloys similar to duralumin made in other countries than Germany

Date: May 1925
Creator: Meissner, K L
Description: Attempts by other countries to develop patents for alloys similar to duralumin are presented. Duralumin is aluminum alloyed with 3.5-4.5% copper, 0.5% magnesium, and 0.25-1% of manganese.
Contributing Partner: UNT Libraries Government Documents Department
An altitude chamber for the study and calibration of aeronautical instruments

An altitude chamber for the study and calibration of aeronautical instruments

Date: November 1925
Creator: Reid, J E & Kirchner, Otto E
Description: The design and construction of an altitude chamber, in which both pressure and temperature can be varied independently, was carried out by the NACA at the Langley Memorial Aeronautical Laboratory for the purpose of studying the effects of temperature and pressure on aeronautical research instruments. Temperatures from +20c to -50c are obtained by the expansion of CO2from standard containers. The chamber can be used for the calibration of research instruments under altitude conditions simulating those up to 45,000 feet. Results obtained with this chamber have a direct application in the design and calibration of instruments used in free flight research.
Contributing Partner: UNT Libraries Government Documents Department
Altitude of equilibrium of an airship

Altitude of equilibrium of an airship

Date: March 1925
Creator: Nobile, Umberto
Description: This report details the procedure followed in establishing a general formula enabling the calculation of the maximum altitude attainable statically.
Contributing Partner: UNT Libraries Government Documents Department
Annual report for the National Advisory Committee for Aeronautics (10th).administrative report including Technical Reports nos. 186 to 209

Annual report for the National Advisory Committee for Aeronautics (10th).administrative report including Technical Reports nos. 186 to 209

Date: January 1, 1925
Creator: unknown
Description: Report includes the National Advisory Committee for Aeronautics letter of submittal to the president, congressional report, summaries of the committee's activities and research accomplished, bibliographies, and financial report.
Contributing Partner: UNT Libraries Government Documents Department
The application of propeller test data to design and performance calculations

The application of propeller test data to design and performance calculations

Date: January 1925
Creator: Diehl, Walter S.
Description: This report is a study of a test data on a family of Durand's propellers (nos. 3, 7, 11, 82, 113, 139), which is fairly representative of conventional design. The test data are so plotted that the proper pitch and diameters for any given set of conditions are readily obtained. The same data are plotted in other forms which may be used for calculating performance when the ratio of pitch to diameter is known. These new plots supply a means for calculating the performance, at any altitude, of airplanes equipped with normal or supercharged engines. The coefficients used and the methods of plotting adopted in this report coordinate the results of a few tests into complete families of curves covering the entire range of p/d ordinarily used. This method of analyzing test data enables an investigator to plan tests systematically and leads to useful application of test data.
Contributing Partner: UNT Libraries Government Documents Department
Astronomical methods in aerial navigation

Astronomical methods in aerial navigation

Date: January 1, 1925
Creator: Beij, K. Hilding
Description: The astronomical method of determining position is universally used in marine navigation and may also be of service in aerial navigation. The practical application of the method, however, must be modified and adapted to conform to the requirements of aviation. Much of this work of adaptation has already been accomplished, but being scattered through various technical journals in a number of languages, is not readily available. This report is for the purpose of collecting under one cover such previous work as appears to be of value to the aerial navigator, comparing instruments and methods, indicating the best practice, and suggesting future developments. The various methods of determining position and their application and value are outlined, and a brief resume of the theory of the astronomical method is given. Observation instruments are described in detail. A complete discussion of the reduction of observations follows, including a rapid method of finding position from the altitudes of two stars. Maps and map cases are briefly considered. A bibliography of the subject is appended.
Contributing Partner: UNT Libraries Government Documents Department
Atomization of liquid fuels. Part I

Atomization of liquid fuels. Part I

Date: September 1925
Creator: Kuehn,
Description: In the present treatise we will consider chiefly the problem of solid injection in comparison with air injection. On leaving the valve or nozzle through one or more small openings, the fuel is split up into innumerable fine drops, which penetrate the combustion chamber in divergent directions in the form of a conical jet. The efficiency of this jet is judged from the following three viewpoints: 1) with respect to the fineness of atomization; 2) with respect to the direction or distribution of sprayed particles; 3) with respect to the penetration of the particles.
Contributing Partner: UNT Libraries Government Documents Department
Atomization of liquid fuels. Part II

Atomization of liquid fuels. Part II

Date: September 1925
Creator: Kuehn, R
Description: This report describes the design and operation of a nozzle to inject fuel into an engine. The design of the nozzle is open, without any compulsory or automatic stop-valve. The fuel injection is regulated simply by the pressure and the adjustment of the fuel pump.
Contributing Partner: UNT Libraries Government Documents Department
Atomization of liquid fuels. Part III

Atomization of liquid fuels. Part III

Date: September 1925
Creator: Kuehn, R
Description: This report provides a critical discussion of the results of the experiments conducted in the previous NACA-TM's 329 and 330. The main object of this investigation was to determine the size of the drops in mechanical atomization.
Contributing Partner: UNT Libraries Government Documents Department
The calculation of wing float displacement in single-float seaplanes

The calculation of wing float displacement in single-float seaplanes

Date: March 1, 1925
Creator: Warner, Edward P
Description: None
Contributing Partner: UNT Libraries Government Documents Department
Calculation of wing spars of variable cross-section and linear load

Calculation of wing spars of variable cross-section and linear load

Date: March 1, 1925
Creator: Kirste, Leon
Description: The calculation of wing spars of constant cross-section and load has been thoroughly treated by a large number of authors. Such is not the case,however, regarding the calculation of wing spars whose section and linear load diminish toward the ends, as in wings of trapezoidal contour and decreasing section.
Contributing Partner: UNT Libraries Government Documents Department
Characteristics of a single float seaplane during take-off

Characteristics of a single float seaplane during take-off

Date: January 1925
Creator: Crowley, J. W., Jr. & Ronan, K. M.
Description: At the request of the Bureau of Aeronautics, Navy Department, the National Advisory Committee for Aeronautics at Langley Field is investigating the get-away characteristics of an N-9H, a DT-2, and an F-5l, as representing, respectively, a single float, a double float, and a boat type of seaplane. This report covers the investigation conducted on the N-9H. The results show that a single float seaplane trims aft in taking off. Until a planing condition is reached the angle of attack is about 15 degrees and is only slightly affected by controls. When planing it seeks a lower angle, but is controllable through a widening range, until at the take-off it is possible to obtain angles of 8 degrees to 15 degrees with corresponding speeds of 53 to 41 M. P. H. or about 40 per cent of the speed range. The point of greatest resistance occurs at about the highest angle of a pontoon planing angle of 9 1/2 degrees and at a water speed of 24 M. P. H.
Contributing Partner: UNT Libraries Government Documents Department
Charts for graphical estimation of airplane performance

Charts for graphical estimation of airplane performance

Date: January 1925
Creator: Diehl, Walter S.
Description: This report contains a series of charts which were developed in order to simplify the estimation of airplane performance. Charts are given for estimating propeller diameter and efficiency, maximum speed, initial rate of climb, absolute ceiling, service ceiling, climb in 10 minutes, time to climb to any altitude, maximum speed at any altitude, and endurance. A majority of these charts are based on the equations given in NACA Technical Report no. 173. Plots of pressure and density against altitude in standard air are also given for convenience. It must be understood that the charts giving propeller diameter, maximum speed, initial rate of climb, absolute ceiling, and speeds at altitudes are approximations subject to considerable error under certain conditions. These particular charts should not be used as a substitute for detailed calculations when accuracy is required, as, for example, in military proposals. (author).
Contributing Partner: UNT Libraries Government Documents Department
Coal-Mine Fatalities in the United States, 1924

Coal-Mine Fatalities in the United States, 1924

Date: 1925
Creator: Adams, William W.
Description: Report compiled by the U.S. Bureau of Mines including statistics on fatalities in coal mines located in the United States as well as data regarding the various operations (e.g., number of miners employed and average production). The information is organized into tables for comparison and the text draws some overall conclusions in the summary.
Contributing Partner: UNT Libraries Government Documents Department
Comparison of model propeller tests with airfoil theory

Comparison of model propeller tests with airfoil theory

Date: January 1, 1925
Creator: Durand, William F & Lesley, E P
Description: The purpose of the investigation covered by this report was the examination of the degree of approach which may be anticipated between laboratory tests on model airplane propellers and results computed by the airfoil theory, based on tests of airfoils representative of successive blade sections. It is known that the corrections of angles of attack and for aspect ratio, speed, and interference rest either on experimental data or on somewhat uncertain theoretical assumptions. The general situation as regards these four sets of corrections is far from satisfactory, and while it is recognized that occasion exists for the consideration of such corrections, their determination in any given case is a matter of considerable uncertainty. There exists at the present time no theory generally accepted and sufficiently comprehensive to indicate the amount of such corrections, and the application to individual cases of the experimental data available is, at best, uncertain. While the results of this first phase of the investigation are less positive than had been hoped might be the case, the establishment of the general degree of approach between the two sets of results which might be anticipated on the basis of this simpler mode of application seems to have been ...
Contributing Partner: UNT Libraries Government Documents Department
The comparison of well-known and new wing sections tested in the variable density wind tunnel

The comparison of well-known and new wing sections tested in the variable density wind tunnel

Date: May 1, 1925
Creator: Higgins, George J
Description: Three groups of airfoils have been tested in the variable density wind tunnel. The first group contains three airfoils. The second group is a systematic series of twenty-seven airfoils. The third group consists of several frequently used wing sections.
Contributing Partner: UNT Libraries Government Documents Department
FIRST PREV 1 2 3 4 5 NEXT LAST