B.E.A. meeting record of 17 January 1961: Bourgard air suspension versus hydropneumatic

In this document

This printed form from the Automotive Design Office (B.E.A.) of Citroën documents a work session held on 17 January 1961 at 2 p.m., in Mr. Cadiou's office, bringing together Cadiou, Magès and Descor[be] p. 7. An annotation refers to a previous session on 27 April 1960 ("See session 440 of 27-4-60").

Comparison of the two suspensions

The subject displayed is the "Update on air suspension" p. 7. The text mentions the Bourgard suspension, presented as prioritizing "flexibility above all", but penalized by significant friction: the large-diameter pistons require large seal surfaces, which according to the document makes an air suspension with large pistons difficult p. 7.

It is noted that "damping can be done" but that anti-roll bars must be added, and that "volumes, dimensions" are larger p. 7. The air suspension "can be compared with the hydropneumatic suspension" p. 7.

Decisions and deadlines

The session sets a deadline for June 1961 p. 7 and proposes to "go all the way, by equipping 3 light cars with springs, hydropneumatic suspension and air suspension" p. 7. There is also talk of responding to Bourgard, in liaison with Messrs. Delerive and Henry Bicherand p. 7.

The document also mentions an ongoing test on "bottoming-out damping", with the hope of final plans "in about ten days", intended for pre-production cars "of the month of May" p. 7. A final remark mentions an application for "truck suspension, 8t tonnage" p. 7.

Context

At Citroën, at the turn of the 1960s, the hydropneumatic suspension — developed by Paul Magès and already in service on the DS since 1955 — coexisted with competing research into compressed air systems, led in particular by an engineer named Bourgard/Bongrand according to other documents in the same file. These technical comparisons are part of a period when several manufacturers were exploring pneumatic solutions alternative to the hydropneumatic, before the latter established itself permanently in the Citroën range.

Archivist's perspective

This document is an internal follow-up piece, brief but dense, which illustrates the role of technical arbiter held by Magès in the face of a competing solution. The tone is that of a work report, with precise technical arguments (friction, sealing, bulk) rather than a definitive judgment.

It seems that this session was an intermediate step in a larger file: it follows a meeting in April 1960 and probably precedes the summary by Magès of 19 June 1961 on the Bongrand affair, which seems to close the comparison mentioned here. It is also in line with the minutes of the meeting of 17 February 1960 on the Bougeard patent, confirming that this confrontation between air suspension and hydropneumatic occupied the B.E.A. for more than a year.