Commercial Aviation in Germany: Past and Future (open access)

Commercial Aviation in Germany: Past and Future

This review of commercial aviation includes postal delivery, package transport, and passenger transport. Both airplanes and airships are covered in this review.
Date: February 1921
Creator: Wronsky, W.
System: The UNT Digital Library
The Aerodynamical Laboratory of the Vienna Technical High School (open access)

The Aerodynamical Laboratory of the Vienna Technical High School

Report presenting a description of the aerodynamics laboratory of the Vienna Technical High School. The main focus of this report is detailing some of the accomplishments that the laboratory has made.
Date: February 1922
Creator: Katzmayr, R. & Kirste, L.
System: The UNT Digital Library
Marking Airdromes (open access)

Marking Airdromes

Necessity of adopting for all aviation fields, civil or military, a single system of markers for giving the direction for starting and landing (with an automatic indicator of the direction of the wind) and of indicating the good part of the field.
Date: February 1922
Creator: James, P.
System: The UNT Digital Library
Deterioration of Airplane Fabrics (open access)

Deterioration of Airplane Fabrics

The observation that airplane fabrics, after long use, lose their original strength, caused the German Experimental Institute for Aviation to carry out a series of experiments on the effect of weathering on the cloth covering of airplane wings and fuselages.
Date: February 1922
Creator: Wendt, F.
System: The UNT Digital Library
Aerial Transportation (open access)

Aerial Transportation

Report discussing the origin of air traffic dates from the war. The important development of aeronautic industries and the progress made in recent years, under the impelling force of circumstances, rendered it possible, after the close of hostilities, to consider the practical utilization of this new means of economic expansion.
Date: February 1922
Creator: Pierrot
System: The UNT Digital Library
The Efficiency of a Wind Tunnel (open access)

The Efficiency of a Wind Tunnel

If, by some means, a steady state of motion of a perfect fluid were established in an ideal wind tunnel, there would be no losses, and the motion would persist indefinitely. In the actual tunnel, the function of the motor-fan group is overcome by the total loss of head in the tube due to friction and eddies.
Date: February 1922
Creator: Miller, William H.
System: The UNT Digital Library
NACA Conference on Engine Stall and Surge (open access)

NACA Conference on Engine Stall and Surge

A compilation of the six technical papers presented at the NACA Conference on Engine Stall and Surge on February 3, 1955 at the Lewis Flight Propulsion Laboratory. A list of conference attendees is also provided.
Date: February 3, 1955
Creator: unknown
System: The UNT Digital Library
Manometer for Recording Air Speed (open access)

Manometer for Recording Air Speed

If it is desired to record the pressure difference given a gauge, the manometer must answer the following conditions: 1) It must respond quickly so that all speed variations will be correctly recorded; 2) It must not be affected by rectilinear or curvelinear accelerations. Hence, movable parts must be counterbalanced. An instrument which met these criteria is discussed as well as details of construction.
Date: February 1922
Creator: Wieselsberger, C.
System: The UNT Digital Library
Soaring Without Rising Currents (open access)

Soaring Without Rising Currents

Memorandum describing the main problem of soaring flight, which is that it is difficult to maintain altitude and to engage in indefinite continuation of flight without dependence on rising currents from any source. The best chance of success involves utilizing energy stored in the air when the wind speed is constantly and rapidly varying.
Date: February 1923
Creator: Warner, Edward P.
System: The UNT Digital Library
Rules and Regulations of the 1922 Rhön Soaring Flight Contest (open access)

Rules and Regulations of the 1922 Rhön Soaring Flight Contest

Rules, regulations, announcements and lists of personnel for the Rhön Soaring-Flight Contest are presented.
Date: February 1923
Creator: unknown
System: The UNT Digital Library
Lessons of the 1922 Rhön Soaring Flights (open access)

Lessons of the 1922 Rhön Soaring Flights

Innovations in design and technique from the Rhön soaring contest are presented in this report.
Date: February 1923
Creator: Prandtl, L.
System: The UNT Digital Library
Experimental Investigations Concerning the Limits of Detonation in Gaseous Mixtures: Part 2 (open access)

Experimental Investigations Concerning the Limits of Detonation in Gaseous Mixtures: Part 2

Memorandum presenting an investigation concerning the limits of detonation in gaseous mixtures. In regards to the results, by progressive dilution of the explosive, the course of the chemical reaction becomes slower and slower until finally the transformation within the reaction zone becomes so slow that it is not there completed.
Date: February 1930
Creator: Wendlandt, Rudolf
System: The UNT Digital Library
On the Calculation of Flow Past an Infinite Screen of Thin Airfoils (open access)

On the Calculation of Flow Past an Infinite Screen of Thin Airfoils

This report deals with the flow past an infinite screen of thin airfoil (two-dimensional problem). The vortex distribution across the profile is established with appropriate expansion in series and the velocity distribution lift, moment, and profile shape deduced. Inversely, the distribution is deduced from the vorticity. The method is the extension of the Birnbaum-Glauert method for the isolated wing.
Date: February 1941
Creator: Pistolesi, E.
System: The UNT Digital Library
Comparison of Automatic Control Systems (open access)

Comparison of Automatic Control Systems

This report deals with a reciprocal comparison of an automatic pressure control, an automatic rpm control, an automatic temperature control, and an automatic directional control. It shows the difference between the "faultproof" regulator and the actual regulator which is subject to faults, and develops this difference as far as possible in a parallel manner with regard to the control systems under consideration. Such as analysis affords, particularly in its extension to the faults of the actual regulator, a deep insight into the mechanism of the regulator process.
Date: February 1941
Creator: Oppelt, W.
System: The UNT Digital Library
The theory of plasticity in the case of simple loading accompanied by strain-hardening (open access)

The theory of plasticity in the case of simple loading accompanied by strain-hardening

The author has previously shown that a deformation theory of plasticity is entirely adequate when the loading is simple; that is, when all the applied forces grow in proportion to a single parameter. The author now shows how a general plasticitytheory for any complex loading may be constructed by successively adding quantities of the nature of correction terms to the deformation theory. All of the theories of plasticity so far suggested for the complex loading condition are shown to be special cases of this general theory.
Date: February 1949
Creator: Ilyushin, A. A.
System: The UNT Digital Library
The Stresses in Stiffener Openings (open access)

The Stresses in Stiffener Openings

The present study treats as a typical example a ring the center line of which is produced by the intersection of two circular cylinders of different diameter. Three load cases are analyzed: (1) Axial and circumferential stresses in both cylinders, the cylinder stresses themselves to be in the ratio conformal to the cylinders loaded under internal pressure. (2) Pure longitudinal tension in the large cylinder. (3) Pure shear (torsion) in the large cylinder.
Date: February 1942
Creator: Marguerre, K.
System: The UNT Digital Library
Statics of Circular-Ring Stiffeners for Monocoque Fuselages (open access)

Statics of Circular-Ring Stiffeners for Monocoque Fuselages

"For circular-ring stiffeners in monocoque fuselages the bending moments, axial forces, and shear forces under the action of applied external forces or a moment are accurately computed by known methods. Circular-ring stiffeners with variable moments of inertia are likewise considered. In comparison with the step-by-step and partially graphical procedure, the one here described is a more accurate and at the same time a simpler method" (p. 1).
Date: February 1942
Creator: Stieda, W.
System: The UNT Digital Library
Gas-Dynamic Investigations of the Pulse-Jet Tube, Parts 1 and 2 (open access)

Gas-Dynamic Investigations of the Pulse-Jet Tube, Parts 1 and 2

Based upon a simplified representation of the mode of operation of the pulse-jet tube, the effect of the influences mentioned in the title were investigated and it will be shown that, for a jet tube with a form designed to be aerodynamically favorable, the ability to operate is at least questionable. This investigation will account for the important practical observation made by Paul Schmidt that the ratio of the effective valve cross-sectional area to the tube cross section may not be of any random magnitude and will explain why at too great flight speeds the jet tube ceases to operate. Chemical an thermodynamic processes (for example, constituents or mode of fuel-air-mixture formation or heat losses) are unimportant in this regard.
Date: February 1947
Creator: Schultz-Grunow, F.
System: The UNT Digital Library
Effect of Fuselage and Engine Nacelles on Some Aerodynamic Properties of an Airplane Wing (open access)

Effect of Fuselage and Engine Nacelles on Some Aerodynamic Properties of an Airplane Wing

"With the aid of the method of J. Lotz, the writer undertook to solve theoretically the lift distribution along the span of an airplane wing, when the outline of the wing is uneven. This problem arises in the case of a mid-wing monoplane with embedded engine nacelles. The fuselage and the nacelles were considered as aerodynamically profiled, that is, as lift-producing parts. The task was therefore to determine not only the disturbance caused by the fuselage and nacelles, but also their share in the total lift of the wing" (p. 1).
Date: February 1934
Creator: Vladea, Joan
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
Impact on a Compressible Fluid (open access)

Impact on a Compressible Fluid

"Upon impact of a solid body on the plane surface of a fluid, there occurs on the vetted surface of the body an abrupt pressure rise which propagates into both media with the speed of sound. Below, we assume the case where the speed of propagation of sound in the body which falls on the surface of the fluid may be regarded as infinitely large in comparison with the speed of propagation of sound in the fluid; that is, we shall assume that the falling body is absolutely rigid. IN this case, the entire relative speed of the motion which takes place at the beginning of the impact is absorbed by the fluid" (p. 1).
Date: February 1958
Creator: Egorov, I. T.
System: The UNT Digital Library
Wind-Tunnel Corrections at High Subsonic Speeds Particularly for an Enclosed Circular Tunnel (open access)

Wind-Tunnel Corrections at High Subsonic Speeds Particularly for an Enclosed Circular Tunnel

A review of existing publications on wind-tunnel corrections is followed by an approximate method for determining the corrections due to model and wake displacement and to lift. Relations are investigated for fuselages and wings of various spans in closed circular tunnels. A comparison is made between the computations and the tests in the DVL high-speed wind tunnel.
Date: February 1952
Creator: Göthert, Bernhard Hermann
System: The UNT Digital Library
Ice Formation on Wings (open access)

Ice Formation on Wings

This report makes use of the results obtained in the Gottingen ice tunnel in which the atmospheric conditions are simulated and the process of ice formation photographed. The effect of ice formation is threefold: 1) added weight to the airplane; 2) a change in the lift and drag forces; 3) a change in the stability characteristics.
Date: February 1939
Creator: Ritz, L.
System: The UNT Digital Library
Comparison of Theory With Experiment in the Phenomenon of Wing Flutter (open access)

Comparison of Theory With Experiment in the Phenomenon of Wing Flutter

Direct measurements were undertaken at the Aeronautics Laboratory in Turin of the aerodynamic actions on an oscillating wing. The tests conducted had as their essential object the examination of the operation of apparatus designed for this measurement. The values experimentally obtained for the aerodynamic coefficients are in good agreement with the theory of oscillatory motion of the wing of finite span and show clear deviation from the values obtained by theory of plane motion.
Date: February 1939
Creator: Cicala, P.
System: The UNT Digital Library