This report examines the idea of coupling numerous engines together to turn a single propeller, which the author feels would free aircraft design from the problems of multi-engine and propeller design.

In order to determine the maximum and the most favorable pitch for a propeller, it was found desirable to investigate the dependence of propeller efficiency on the angle of attack of the propeller blade. The results of a few experiments are given to show that propeller blades conduct themselves just like airplane wings with reference to the dependence of their efficiency on their angle of attack.

This report contains a list of the courses relating to aeronautics announced in Germany, both in the technical high schools and in the universities.

"The proposed device tends to render the lateral stabilization of airplanes easier and more efficacious. The proposed solution is to mount the ailerons independently, in such a manner that they can turn freely, under the action of the relative wind, about an axis located in front of the extreme position of the center of the lift" (p. 1).

Report presenting a description of the interaction between the dynamometer hub and the flywheel of the engine in aircraft. The negative rotary moments in propellers generally allow for the cessation of one cylinder without any lifting on the part of the propeller, and without depriving the engine of its flywheel.

Essential principles for building small diesel engines and also structural details so far as feasibility are presented.

Report presenting a description of fluid compasses that are being used in aircraft, including why magnetic compasses are not usable. Details of the distant compass are provided, which is an improved form of the compass that has a practical application in seaplanes.

A method is presented for soldering aluminum to other metals. The method adopted consists of a galvanic application to the surface of the light-metal parts to be soldered, of a layer of another metal, which, without reacting electrolytically on the aluminum, adheres strongly to the surface to which it is applied, and is, on the other hand, adapted to receive the soft solder. The metal found to meet the criteria best was iron.

"On April 15, 1920, the under Secretary of State for Aeronautics and Aerial Transport decided to adopt as Standard Atmosphere for official airplane tests in France, the atmosphere defined by the following law, known as the Law of the S.T.You.(Technical Section of Aeronautics): From 0 to 11,000 m. - 0=15-0.0065 Z and above 11,000 m. - 0= -56.5 degrees being the temperature in centigrade degrees at altitude Z expressed in meters. For altitude 0 the pressure is 760 mm of mercury. In the magazine "L'Aeronautique" Mr. A. Toussaint has already written at length on the first studies which led to the elaboration of this law. Since that time the results obtained have been confirmed by fuller and more abundant data which have justified the official adoption of the Law of the S.T.Ae" (p. 1).

Report presenting an experiment in the Rechlin airdrome in the fall of 1918 to determine the influence of struts and stays on the speed of an airplane. Results indicated that only a slight increase in horizontal speed was shown in a stayless airplane, but it had considerably greater climbing speed.

A definition of "stalled fight" is presented as well as a detailed discussion on the how and why it occurs. Some suggestions are made to prevent its occurrence such as carrying an air speed instrument in the airplane.

Report presenting a discussion of the creation of a suitable aviation school and some of the characteristics that should be considered in terms of hiring personnel, creating a curriculum, and obtaining equipment.

Report presenting a discussion of ways to save fuel on traffic flights, including some calculations that can be used for determining fuel efficiency. The primary ways of lessening fuel consumption include flying with a throttled engine and diminished speed.

This report presents a series of tests conducted to verify the formula for thrust P = q(exp 2) D(exp 2) V(exp 2), where P represents thrust, V the velocity of the airstream, D the diameter of the propeller, and q the lifting quality of a comparative propeller which is called the conjugate propeller.

This report details the Rumpler Limousine which was a further development of the well known type 5 A 2. The fuselage, engine, cabin, wings, controls, and landing gear are all discussed.

This report presents a method of calculating polar curves which is at least as precise as graphical methods, but it more rapid. Knowing the wind tunnel test of a wing and the performances of an airplane of the same profile, it is easy to verify the characteristic coefficients and, at the same time, the methods determining induced resistances.

This report presents experiments and calculations for the purpose of determining the landing gear requirements upon the water. Moving pictures are given which furnish data and also may give both the magnitude and direction of the forces acting. Different classes of seaplanes are examined and proposals for calculation instructions are given.

The first part of this report details the efficiency and economy of airship travel, while the second part presents methods of economic efficiency with regards to construction, cost of upkeep and operation, and the establishment of airship lines.

Comparing the results of the calculations for computing the mean pressure of an aviation engine for any number of revolutions, with those of experiment, the writer, by numerous examples, shows the perfect agreement between them. This report will show that, by means of a special abacus, an engineer can instantly plot the characteristics of an engine.

The author presents a comparison and combination of the numerical and geometrical determinations of the maximum M, when calculating the maximum bay moment.

The author presents a comparison and combination of the numerical and geometrical determinations of the maximum M, when calculating the maximum bay moment.

Memorandum presenting a glossary of terms used to describe flying boat hulls and the elements used in construction.

As the purpose of the report is to transmit as smoothly and as easily as possible, certain facts and ideas, to the average person likely to read it, it should be written in a full and simple enough manner to be comprehended by the least tutored, and still not be boring to the more learned readers.

This report presents a discussion of how to determine the location of a line or surface from experimental data. What we desire to know practically is the number of ordinates required to obtain a certain probable precision in drawing a line or surface.