In Partnership With

August 1, 1917

The Type F Dirigibles of the Societá Leonardo Da Vinci

Extracts From Inspectors’ Manual Aviation Section, Signal Corps, U.S.A.

National Physical Laboratory Report for 1916-17

2425

The Type F Dirigibles of the Societá Leonardo Da Vinci

The “ F ” type of dirigible belongs to the semi-rigid class. Its main characteristic features are: Double envelope. Gas envelope ritted with transverse and longitunal diaphragms. Rigid truss girder running in the direction from stern to bow.
3031

Extracts From Inspectors’ Manual Aviation Section, Signal Corps, U.S.A.

All linen used in airplane construction should be up to the following specifications: Free from all knots or kinks. Without sizing or filling. As near white as possible. Weight, between 3.5 and 4.5 ounces per square yard. Strength per inch should comply with Signal Corps specifications.

4041

National Physical Laboratory Report for 1916-17

The annual meeting of the General Board of the National Physical Laboratory was held at the Laboratory at Teddington, Eng., June 19th. The President of the Royal Society (Sir J. J. Thomson) is chairman of the board, and Lord Rayleigh is chairman of the executive committee.
3233

Course in Aerodynamics and Airplane Design

At the conclusion of the previous section, we drew the bending moment diagram for the upper rear spar as a continuous beam, and found the appropriate reactions. But since the bending moment diagram was drawn for that component of the force in the plane of the lift truss which was in the plane of the spar web, allowance has to be made for it on reverting to the lift truss.

4243

Manufacturers Aircraft Association, Inc., Organized

4243

$640,000,000 Appropriated for Army Aviation

On July 24 President Wilson signed the bill appropriating $640,000,000 for the enlargement of the Air Service of the Army. We give herewith two statements, one by Brig.-Gen. George O. Squier, Chief Signal Officer, and the other by Howard E. Coffin, chairman of the Aircraft Production Board, outlining as far as it is possible to do so, the plans of those charged with the expenditure of the appropriation:
3637

Testing Moisture Content in Lumber

All lumber contains moisture, absolutely dry lumber being impossible, commercially speaking. In small test pieces, or on a laboratory basis, perfectly dry lumber can be obtained. Perfect dryness (often called “bone dry”) is a condition in which all moisture has been evaporated, leaving only dry fibre and a minute amount of granular residue from sap (nearly negligible and disregarded hereafter).

2223

Editorials

3839

New City Planning Problems

3839

Bureau of Standards Test on Ackerman Wheels

Some recent tests have been made at the Bureau of Standards on the 26 x 3 in. Ackerman wheel, weighing 22 lb. complete. The tests were made (a) to determine maximum component parallel to the axis, (b) to determine maximum component perpendicular to the axis, and the hysterisis, if any.
July 151917 August 151917