Note from Paul Magès proposing the monitoring of 10 DS taxis and 10 ID taxis for hydraulic tests (2 July 1959)

In this document

This memorandum from the B.E.A. (Automotive Design Office) at Citroën, addressed by Paul Magès to Mr. Duclos (with copies to Messrs. Cadiou, Hermet, Louis, and Pompon), summarizes a conversation dated 9 June 1959 p. 281 — the note itself being typed and dated 2 July 1959 according to the handwritten annotation in the margin p. 281.

The initial observation

Magès explains that it is difficult for the B.E.A. and the laboratory to reproduce real-world customer usage conditions internally, and that otherwise, it would be necessary to considerably increase the number of test cars and personnel p. 281.

The Caribbean experience

Since November 1958, observations conducted in Guadeloupe and Martinique regarding the hydraulic system have shown that it is possible to "monitor the evolution of components remotely" provided that precise instructions are given p. 281. Magès concludes that this monitoring must be replicated in France.

The taxi program

The concrete proposal concerns the monitoring of 10 DS taxis and 10 ID taxis, on which "new or modified" hydraulic, mechanical, and electrical components would be installed and measured periodically (every 6 weeks), in a "pre-production" phase, before any final ordering p. 281-282.

Three examples of modifications to be verified are cited: the single-cylinder HP pump on the ID (mineral oil sealing), the DS-ID circuit breaker, and the hydraulic circuit oil p. 282.

The text specifies that no modification requiring the approval of the Mines Department would be applied, and that Citroën could provide an additional vehicle to keep a taxi available for examination at all times p. 281-282. The previous experience with three private DS taxis, monitored by the B.E.A. for over a year, is also mentioned as a starting point p. 281.

Context

At the end of the 1950s, the DS (1955) and then the ID (1957) were the showcases for the hydropneumatic suspension developed by Paul Magès. Parisian taxis, which covered high mileage and operated in demanding urban conditions, traditionally served as an excellent full-scale "rolling laboratory" for manufacturers, allowing for the testing of component reliability well before their mass-production rollout — a common practice in the automotive industry at the time.

Archivist's perspective

This document clearly illustrates Magès's working method: articulating laboratory tests and large-scale field feedback. It also shows the constant concern for reliability that characterized his approach to hydraulic components, in continuity with his pre-war work on suspension (see the 1944 hydropneumatic suspension plans).

It seems that this note is part of a larger file on the monitoring and continuous improvement of DS/ID hydraulic components, as suggested by the summary of folder 41-59 dedicated precisely to these developments.