Many treatises in regard to construction of airship sheds are lacking in data on air currents, for which reason this phase of the problem will be here thoroughly discussed in connection with the accompanying photographs of currents.

Memorandum presenting a description of the development of the mooring mast and how it contributes to the technique of landing large airships. Some of its fundamental requirements and how it can factor into safe landings are provided.

The stressing of an airship depends on three nonuniformly distributed forces: air forces; the distribution of acceleration forces; and how the air pressure is distributed on the hull. This report examines the stresses and comes to conclusions on the size of airships.

Memorandum presenting an overview of ultra-light alloys and their potential use on an aircraft. A definition of ultra-light alloys, some of the present possibilities of ultra-light alloys, and some of the principles governing the use of the alloys in aircraft are provided.

Memorandum presenting the history and development of airships. Tables containing information and statistics regarding some of the current airships are provided.

The causes of the destruction of the Dixmude are discussed and some conclusions are drawn. The author believes a gasoline fire instead of a lightning strike was probably responsible, but the public believes otherwise.

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. A description of various materials that some have attempted to patent are provided.

The economic costs and benefits of speed on airship traffic are calculated and different factors are considered.

"This article is based on the experience of the Schute-Lanz Airship Company in light construction. The object is to stimulate the employment of these methods in other fields of industry" (p. 1).

We propose to make a study of the difficulties in using stressed coverings and their appropriate solutions. Fatigue and buckling are also discussed.

The investigation was limited chiefly to the region of high angles of attack since it is only in this region that any considerable change in the character of the flow can be expected from such artificial aids. The slot, through which compressed air was blown, was formed by two pieces of sheet steel connected by screws at intervals of about 5 cm. It was intended to regulate the width of the slot by means of these screws. Much more compressed air was required than was originally supposed, hence all the delivery pipes were much too small. This experiment, therefore, is to be regarded as only a preliminary one.

"This work proposes to sketch, in broad outline, the status of airship construction in the various countries, at a time when commerce over great distances might be finally opened up to the airship through the performances of the "Graf Zeppelin." After a short historical review, a survey of the most important rigid and semirigid airships built since 1925, their differences and special problems, is made. In more detailed treatment, the framing construction of the more recent rigid airships and some especially interesting structural questions are investigated" (p. 1).

"Many experimental arrangements of varying kind involve the problems of assuring a large, steady air stream both as to volume and to time. For this reason a separate discussion of the methods by which this is achieved should prove of particular interest. Motors and blades receive special attention and a review of existent wind tunnels is also provided" (p. 1).

This report is a recounting of the German investigation of the crash of a commercial Junkers F 13 ge in England. The English report is examined and compared with the German interpretation of the accident.

The present state of the problem of materials in airplane construction is studied on the basis of data giving the principal characteristics of different materials and showing how they affect the form of airplane parts.

"Results of measurements on a shrouded propeller are given. The propeller is designed for the high ratio of advance and high thrust loading. The effect of the shape of propeller and shroud upon the aerodynamic coefficients of the propulsion unit can be seen from the results" (p. 1).

Goldbeater's skin, which is the prepared outside membrane of the large intestine of an ox, is examined as a balloon fabric and details of how goldbeater's skin is prepared for use are provided. The construction techniques employed by Germany, France, and England are all discussed.

The purpose of this paper is to summarize the present status of the problem of mooring airships. Mooring with one, two and even three cables are all discussed.

A historical sketch of duralumin is presented, especially in regards to its manufacture by various countries. The properties of duralumin are discussed and strength characteristics listed. Increasing the hardness of duralumin by tempering is discussed as well as the uses of the metal.