In the foregoing remarks I have made an attempt to touch on some of the structural problems met with in cantilever wings, and dealt rather fully with a certain type of single-spar construction. The experimental test wing was a first attempt to demonstrate the principles of this departure from orthodox methods. The result was a wing both torsionally stiff and of light weight - lighter than a corresponding biplane construction.

In order to understand the numerical relations between the air velocity, temperature of the cylinder walls, heat dissipation, cylinder dimensions and type of construction an experimental plant was installed in the Siemens and Halske laboratory. The experimental cylinder was exposed to the air stream of a wind tunnel. The compression chamber was heated by an electrically heated oil bath kept constantly in motion by a stirrer. The wall temperatures were measured by thermocouples.

"The recent trial flights and acceptance tests of the Rohrbach "Romar," the largest seaplane in the world, have yielded results fully confirming the principles followed in its development. Its take-off weight of 19,000 kg, its beating the world record for raising the greatest useful load to 2000 m by almost 2500 kg and its remarkable showing in the seaworthiness tests are the results of intelligent researches, the guiding principles of which are briefly set forth in this article" (p. 1).

This paper calls attention to the desirability of expanding airplane building regulations to include proof of safety for cases of unsymmetrical loading, at least in the structural members which are thereby specially stressed. The flight cases involve increases of the customary load assumptions through rudder deflection and aileron deflection.

Part I of this paper covers the constructional design of metal flying-boat hulls and does not elaborate any further. Part II deals with the actual construction process of the hull.

As a rule, the actual lift distribution at the wing tips shows deviations from the theoretical distribution, so that an approximate evaluation of the distribution may be regarded as satisfactory. After a few brief remarks on the fundamentals of the exact computation, the method will be so presented that the lift distribution for deflected ailerons may be determined for other values of the parameter p from the results already obtained. Coefficients will then be given in the form of diagrams and numerical tables, from which the desired forces and moments can be easily obtained by substitution in the given equations.

This report examines the take-off conditions of airplanes equipped with tractive propellers, and particularly the more difficult take-off of airplanes heavily loaded per unit of wing area (wing loading) or per unit of engine power (power loading).

The calculations in this paper afford an approximate solution of the static stability. A derivation of the formulas for moment coefficient of a wing, moment coefficient of elevator, and the total moment of the combined wing and elevator and the moment coefficient with reference to the center of gravity are provided.

The present report contains the results of a few experiments on three airfoils to which the rear portions, having chords respectively 1/4, 1/3, and 2/5 of the total chords, are hinged so as to form ailerons, especial attention being given to the shape of the slot between the aileron and the main portion of the aileron.

This report presents methods to reduce the incidence of aviation accidents. Some of the methods discussed include enlistment and training of aviators, improvement of controls and control surfaces, and upgrading of power plants.

The structural details such as wings, fuselage, landing gear, and steering organs of German gliders are detailed in this report.

It seems desirable to have some simple method for calculating quickly and with sufficient accuracy: 1) the correct position of the center of gravity; 2) the requisite tail-group dimensions; 3) and the course of the wing and tail-group moments. In out deductions, we will first replace the biplane (disregarding the effect of stagger, decalage and induced drag) by an equivalent monoplane, whose dimensions and position in space can be approximately determined in a simple manner.

The staff and construction of the Institute are described as well as a variety of experiments and researches being conducted there. The six sections of the laboratory are described, including the Section for Theoretical Researches, Section for Aerodynamic Researches, Windmill Section, Section for Engine-Propeller Groups, Section for Material Testing, and Section for Instrument Making. Special attention is given to the various wind tunnels and testing facilities present.

Memorandum describing warning or correcting devices based on the registering of two distinct factors, the air speed and the angle of attack. The authors of the report define the conditions for the flight of an airplane and then study the causes of stalled flight in the different cases where it can occur.

The task of removing the boundary layer by suction consists in producing, in place of the ordinary flow with the formation of vortices, another kind of flow in which the vortices are eliminated by drawing small quantities of fluid from certain points on the surface into the interior of the body. The experiments with a sphere, which constitute the subject of this report, were made early in the present year .

In order that the method may be more easily understood, we will first consider the simpler case when there is no lift, but only drag, and when the streamlines at the measuring point behind the obstacle are nearly parallel. Moreover, the flow is assumed not to deviate much from the two-dimensional flow.

The designing of an airplane requires an accurate knowledge of the aerodynamic properties of its wings, as expressed in the polar diagram. It is important to continue the theoretical researches on the aerodynamic phenomena of wings, in order to determine by calculation, their fundamental characteristics and to increase and formulate our knowledge in this field.

This airship was built by the Zeppelin Airship Company at Friedrichshafen in 1923-4, for the United States Navy, as the reparations service of the German Government in fulfillment of the treaty of peace. A description of the design, components, flight characteristics, blueprints, and photographs are provided.

"These notes are intended to furnish practical and general data on the effect of altitude on engine power. The effective horsepower of an engine is a function of the mean pressure of the fluid acting on the pistons, of the R.P.M. of the engine and of the mechanical efficiency" (p. 1).

The knowledge gained from previous experiments and reports was utilized for the construction of a dynamometer hub for 200 mkg (134.4 ft.-lb.) and 1200 kg (2646 lb.) thrust suited for a Liberty "12" engine. A reversing device is also described.

Memorandum presenting a description of a competition to produce an airplane suitable for school work. The characteristics evaluated included the speed range, take off, landing, reliability, and high and low speed are provided. A variety of monoplanes and biplanes were entered and a description of each and their blueprints are provided.

This article presents a discussion of the relative merits between monoplanes and biplanes. A comparison of the aerodynamic qualities and advantages of both types are provided.

Memorandum presenting a method of calculating the dead reckoning in aerial navigation.

Different aspects of an airship line between Lisbon and Rio de Janeiro are presented. Some of the factors discussed are: the number of passengers, fuel consumption, design, itinerary, airports, flight times, and income.