Technical monitoring note: the manufacture of oxygen cylinders for aviation (1944)

In this document

This page p. 23 is a handwritten technical monitoring note, taken on a letterhead form "Sté AME A. Citroën", summarizing an article from the journal Aircraft Production of September 1944, referenced "Inter Technique. — IS 4489".

The described process

The note mentions a manufacturing process for oxygen cylinders for aviation, implemented by the British company "Projectile and Engineering C° Ltd" p. 23.

Dimensions and pressures recorded

Finally, the note specifies a manufacturing detail: a "wound steel wire embedded in soft solder" p. 23, which suggests a technique of reinforcing the cylinder by hooping.

The rest of the ruled page is blank.

Context

In 1944, France was still under occupation and then in the process of liberation; French engineers, like those at Citroën, nevertheless followed the foreign technical press — here British — to keep themselves informed of industrial innovations, particularly those linked to the aeronautical war effort.

This period corresponds precisely to the time when Paul Magès, who joined the design office following his work on the braking limiter for the TUB van, established the first plans for hydropneumatic suspension with differential interaction on 17 February 1944. Oxygen cylinders for aircraft, subjected to high pressures at altitude, constitute a subject of transversal technical interest: the issues of material resistance, sealing, and reinforcement by wire winding (a technique close to hooping) potentially interest any engineer working on pressurized components, such as hydraulic cylinders or accumulators.

Archivist's perspective

This document is a simple technological monitoring note, likely written by Paul Magès or one of his collaborators in the design office — where he was then working on hydropneumatic suspension — to stay informed of foreign industrial advances, with no apparent direct and immediate link to this project.

However, it testifies to a methodical curiosity for the manufacturing techniques of pressurized parts — a subject that is not without echoes of the research conducted at the same time on the plans for hydropneumatic suspension with differential interaction, where the mastery of pressures and cylinders was central.

This piece likely belongs to the same work file as the list of problems under study as of 22 February 1944, reflecting the research and technical documentation activity of the department during the year 1944.