The 5- by 7-meter wind tunnel of the DVL (open access)

The 5- by 7-meter wind tunnel of the DVL

The report contains a description of the DVL wind tunnel. According to the cones fixed, an elliptical stream with axes 5 by 7 meters and length 9 meters, or a stream 6 by 8 meters in cross section and 11 meters in length is available. The top speed with the smaller cone is 65 meters per second. The testing equipment consists of an automatic six-component balance and a test rig for propellers and engines up to 650 horsepower.
Date: March 1936
Creator: Kramer, M.
System: The UNT Digital Library
The 1929 Rhon soaring-flight contest (open access)

The 1929 Rhon soaring-flight contest

The limitation of the 1929 contest to performance gliders necessitated the establishment of a formula which would make it possible to distinguish between performance gliders and school and training gliders. The sinking speed was therefore adopted as the basis for such a distinction, and the requirement was made that the sinking speed of a performance glider should not exceed 0.8 m/s. The rest of the report details the different entries with regard to design and performance.
Date: April 1930
Creator: Lippisch, Alexander
System: The UNT Digital Library
The 1933 Contest for the Deutsch De La Meurthe Trophy (open access)

The 1933 Contest for the Deutsch De La Meurthe Trophy

Report discussing the regulations and airplanes participating in the 1933 contest competing for the Deutsch de la Meurthe trophy.
Date: October 1933
Creator: Léglise, Pierre; Hirschauer, L. & Saladin, Raymond
System: The UNT Digital Library
The 1934 Contest for the Deutsch De La Meurthe Trophy (open access)

The 1934 Contest for the Deutsch De La Meurthe Trophy

This report presents a description of the rules, history and new technical innovations in the Deutsch de la Meurthe Cup race of 1934.
Date: February 1935
Creator: Léglise, Pierre
System: The UNT Digital Library
The Aachen Wind-Tunnel Balance (open access)

The Aachen Wind-Tunnel Balance

Report discussing a description of the balance in the Aachen wind-tunnel.
Date: November 1934
Creator: Wieselsberger, C.
System: The UNT Digital Library
Accurate Calculation of Multispar Cantilever and Semicantilever Wings With Parallel Webs Under Direct and Indirect Loading (open access)

Accurate Calculation of Multispar Cantilever and Semicantilever Wings With Parallel Webs Under Direct and Indirect Loading

In the present report the computation is actually carried through for the case of parallel spars of equal resistance in bending without direct loading, including plotting of the influence lines; for other cases the method of calculation is explained. The development of large size airplanes can be speeded up by accurate methods of calculation such as this.
Date: March 1932
Creator: Sänger, Eugen
System: The UNT Digital Library
Activation of hydrocarbons and the octane number (open access)

Activation of hydrocarbons and the octane number

This report presents an examination of the history of research on engine knocking and the various types of fuels used in the investigations of this phenomenon. According to this report, the spontaneous ignition of hydrocarbons doped with oxygen follows the logarithmic law within a certain temperature range, but not above 920 degrees K. Having extended the scope of investigations to prove hydrocarbons, the curves of the mixtures burned by air should then be established by progressive replacement of pure iso-octane with heptane. Pentane was also examined in this report.
Date: October 1939
Creator: Peschard, Marcel
System: The UNT Digital Library
Additional Test Data on Static Longitudinal Stability (open access)

Additional Test Data on Static Longitudinal Stability

From Summary: "The purpose of this investigation was to explore the influence of weights of the controls on the stability with elevator released. The available test data were extended to stability with elevator locked. In this connection the study of the propeller effect seemed of vital importance."
Date: August 1934
Creator: Hübner, Walter
System: The UNT Digital Library
The Aerodynamic Aspect of Wing-Fuselage Fillets (open access)

The Aerodynamic Aspect of Wing-Fuselage Fillets

Report discussing model tests prove the feasibility of enhancing the aerodynamic qualities of wing-fuselage fillets by appropriate design of fuselage and wing roots. Abrupt changes from maximum fuselage height to wing chord must be avoided and every longitudinal section of fuselage and wing roots must be so faired and arranged as to preserve the original lift distribution of the continuous wing. Adapting the fuselage to the curvilinear circulation of the wing affords further improvement. The polars of such arrangements are almost the same as those of the "wing alone," thus voiding the superiority of the high-wing type airplane known with conventional design.
Date: February 1935
Creator: Muttray, H.
System: The UNT Digital Library
Aerodynamic forces and moments of a seaplane on the water (open access)

Aerodynamic forces and moments of a seaplane on the water

From Introduction: "This report gives the results of wind-tunnel tests with a seaplane model as a contribution to the solution of the aerodynamic problems."
Date: November 1933
Creator: Kohler, M.
System: The UNT Digital Library
Aerodynamic principles of the direct lifting propeller (open access)

Aerodynamic principles of the direct lifting propeller

From Summary: "The purpose of this report is to make the complicated processes on the direct-lift propeller amenable to analysis and observation. This is accomplished by placing the physical phenomena, starting with the most elementary process, in the foreground, while limiting the mathematical treatment to the most essential in view of the fundamental defects of the theorems. Comparison with model experiments supplements and corroborates the theoretical results."
Date: January 1934
Creator: Schrenk, Martin
System: The UNT Digital Library
The aerodynamic safety of airplanes (open access)

The aerodynamic safety of airplanes

This report presents several hypotheses regarding airplane safety, mainly concerning the nondimensional coefficient of air, speed, acceleration, and wing area on aerodynamic considerations of safety.
Date: September 1932
Creator: Kahn, Louis
System: The UNT Digital Library
The Aerodynamic Wind Vane and the Inherent Stability of Airplanes (open access)

The Aerodynamic Wind Vane and the Inherent Stability of Airplanes

Report discussing the design of the wind vane described rests on the following line of reasoning: An airplane, originally in equilibrium about its C.G. is assumed to be deflected from this position through an angle (delta)i, the variation (delta)i being so sudden that the path of the C.G. and the airplane speed do not change while it is taking place. The aerodynamic forces acting on the wings, tail surfaces, fuselage, etc., which, as a whole, exerted a zero moment (M(sub G) = 0) about the center of gravity at the instant of equilibrium, now exert a moment M(sub G) not equal to 0.
Date: February 1931
Creator: Lapresle, A.
System: The UNT Digital Library
Aeronautical education and research at the Swiss Institute of Technology in Zurich (open access)

Aeronautical education and research at the Swiss Institute of Technology in Zurich

Progress in the scientific and practical fields of aviation has caused the Swiss Institute of Technology to organize lectures and practical training courses in all three branches of aeronautics and to found centers of scientific research, laboratories, etc., in order to supply the government and industries with scientifically and technically trained engineers.
Date: April 1931
Creator: Karner, L. & Ackeret, J.
System: The UNT Digital Library
The Aeronautical Laboratory of the Stockholm Technical Institute (open access)

The Aeronautical Laboratory of the Stockholm Technical Institute

This report presents a detailed analysis and history of the construction and operation of the aeronautical laboratory of the Stockholm Technical Institute. Engines and balances are discussed and experimental results are also given.
Date: March 1935
Creator: Malmer, Ivar
System: The UNT Digital Library
Air forces and air-force moments at large angles of attack and how they are affected by the shape of the wing (open access)

Air forces and air-force moments at large angles of attack and how they are affected by the shape of the wing

From Summary: "The present report is, in the first place, a compilation of the test results now available from wing tests up to angles of attack 90^o. Reports are also given of tests with monoplane and auxiliary wings in the Gottingen wind tunnel for the purpose of plotting a steadily rising curve of the normal force as a foundation of the angle of attack."
Date: July 1930
Creator: Fuchs, Richard & Schmidt, Wilhelm
System: The UNT Digital Library
An airfoil spanning an open jet (open access)

An airfoil spanning an open jet

From Summary: "The first part of the report treats of the theory involved. The second part describes the experiments performed for the purpose of proving the theory."
Date: September 1933
Creator: Stüper, J.
System: The UNT Digital Library
Airfoil Theory at Supersonic Speed (open access)

Airfoil Theory at Supersonic Speed

From Summary: "A theory is developed for the airfoil of finite span at supersonic speed analogous to the Prandtl airfoil theory of 1918-1919 for incompressible flow. In addition to the profile and induced drags, account must be taken at supersonic flow of still another drag, namely, the wave drag, which is independent of the wing aspect ratio. Both wave and induced drags are proportional to the square of the lift and depend on the Mach number, that is, the ratio of flight to sound speed. In general, in the case of supersonic flow, the drag-lift ratio is considerably less favorable than is the case for incompressible flow."
Date: June 1939
Creator: Schlichting, H.
System: The UNT Digital Library
Airplane Flight in the Stratosphere (open access)

Airplane Flight in the Stratosphere

This brief survey of the problems encountered in high-altitude flight deals in particular with the need for high lift coefficient in the wings, large aspect ratios in the wings, and also the problem of hermetically sealing the cabin.
Date: February 1932
Creator: de Caria, Ugo
System: The UNT Digital Library
Airplane Landing Gear (open access)

Airplane Landing Gear

This report presents an investigation of the design and construction of various types of landing gears. Some of the items discussed include: chassises, wheels, shock absorbers (rubber disk and rubber cord), as well as oleopneumatic shock absorbers. Various types of landing gears are also discussed such as the Messier, Bendix, Vickers, and Bleriot.
Date: July 1931
Creator: Maiorca, Salvatore
System: The UNT Digital Library
Airplane Stability in Taxying (open access)

Airplane Stability in Taxying

The stability analysis of an airplane while rolling is much more simplified to the extent that it can be obtained for numerical data which can be put to practical use in the design of landing gear dimensions. Every landing gear type attains to a critical ground friction coefficient that decides the beginning of instability, i.e., nosing over. This study has, in addition, a certain interest for the use of wheel brakes.
Date: September 1932
Creator: Anderlik, E.
System: The UNT Digital Library
Analysis of Spinning in a Monoplane Wing by the Induction Method as Compared With the Strip Method (open access)

Analysis of Spinning in a Monoplane Wing by the Induction Method as Compared With the Strip Method

The problem of autorotation has been attacked by various authors, in particular Fuchs and Schmidt who applied the so-called strip method which is based upon the assumption that the forces and moments per unit length acting in each section of the wing are equal to those on an infinite cylindrical wing of equal section in an air flow of intensity and direction resulting from the apparent relative motion of this section with respect to the surrounding air. In other words they disregarded the induced velocities, which, however, are of such importance that their omission is bound to result in appreciable errors, as we attempt to prove in this report.
Date: June 1934
Creator: Poggi, L.
System: The UNT Digital Library
Analysis of the Three Lowest Bending Frequencies of a Rotating Propeller (open access)

Analysis of the Three Lowest Bending Frequencies of a Rotating Propeller

From Summary: "The present report is a survey of the existing data for computing the bending frequency and a check on the dependability of the calculating methods."
Date: January 1936
Creator: Liebers, F.
System: The UNT Digital Library
The apparent width of the plate in compression (open access)

The apparent width of the plate in compression

This report discusses an investigation that treats the load capacity of a rectangular plate stressed in compression on one direction (x) beyond the buckling limit and the plate is rotatable (i.e., free from moments) supported at all four sides by bending-resistant beams.
Date: July 1937
Creator: Marguerre, Karl
System: The UNT Digital Library