August 15, 1918

Determination of Permeability of Balloon Fabrics*

Some Outstanding Problems in Aeronautics

The 180 Hp. Mercedes Aero-engine


Determination of Permeability of Balloon Fabrics*

(e) Duration of Test.—The passage of hydrogen through the fabric being a solubility phenomenon, it may be assumed that a certain time must elapse after the fabric is placed in contact with hydrogen before the fabric is saturated with hydrogen and reaches its maximum permeability.


Some Outstanding Problems in Aeronautics

Ten years ago the airplane was a curiosity—a means wherewith, by a tour de force, a man might lift himself from the ground and make a hazardous flight through quiet air—a means to attract curious crowds to fenced-in country fair grounds to witness the marvel of a body heavier than air actually rising from the ground and moving under some measure of control through the air, and returning safely to its starting point.


The 180 Hp. Mercedes Aero-engine

The following report on the design of the new 180 hp. Mercedes engine is based on an examination of the engine (No. 35254) taken from the captured German Albatros biplane D.5.A. (G.97), which was shot down by anti-aircraft fire in the 5th Brigade area on November 14, 1917, and the accompanying data on the design of the engine and the particulars of its general performance, have been compiled from results of tests carried out at the Royal Aircraft Factory.

News of the Fortnight

The Price Fixing Committee has readied an agreement with New England manufacturers on maximum prices for spruce lumber to the Government and others for the period July 19Nov. 1, 1918. The prices of all New England spruce lumber in the States of Maine, New Hampshire, Vermont and Massachusetts shall not exceed the item prices named in the list.

Effect of Initial Stress on Redundant Truss Members

It often occurs, in the stress analysis of a wing truss, that two or more members are supplied to absorb the load at a given point. The solution for the stress is statically indeterminate, but the stresses are easily obtained by the theory of redundant truss members.


German Conceptions in Airplane Construction

The accompanying photographs illustrate some typical examples of recent German airplane construction, which seem to warrant more than passing interest on account of certain interesting features they embody. For the last year or so German airplane constructors have applied in steadily increasing numbers veneer to the construction of airplane bodies.

Digest of the Foreign Aeronautical Press

The A. E. G. Bomber.—Some additional details are now available on the A. E. G. Bomber (which was described in the July 15, 1918, issue of AVIATION), particularly in regard to its camouflage and the type and number of bombs it carries. The camouflage scheme of the A. E. G. consists of a regular pattern of seven hexagons, six of which are colored in pairs black, grayish-blue and green, while the seventh is of purple color.

First Aid in Aero Accidents


The Benz Aluminum Pistons*

A 230-hp. Benz engine, No. 31,560, taken from the Aviatik biplane, G. 130, captured on Feb. 12, 1918, was found to be fitted with aluminum pistons. As these are the first aluminum pistons to be found in a captured enemy aero engine in service, a detailed report of their design, together with a chemical analysis of the alloy, should be of interest.

Where Liberty Airscrews Are Made

The Miami Valley in Ohio is one of the important centers of aircraft production which have sprung up sincs our entry into the Great War. Dayton, in particular, is the home of a great number of factories manufacturing all kinds of aeronautical apparatus, from complete war airplanes to ignition systems for aero-engines and turnbuckles.
August 11918 September 11918