Handwritten note: 'at the limit' test of the 15 H at La Ferté-Vidame (1954)

In this document

This handwritten page, difficult to decipher in places, relates an episode in the development of the 15 H, the version of the Citroën 15 CV equipped with hydropneumatic suspension.

The text mentions Mr. Cadion's "fears" before the "release" of the 15 CV: the new driving sensations led him to say that the road-holding of the 15 H "was not as good as the 15 with [torsion] bars" p. 1.

To settle the matter, "head-to-head" tests were organised on the La Ferté-Vidame track, "in search of the limit speed for cornering". The author describes the exercise as "Operations that were not very pleasant for me; it is dangerous", while specifying that it allowed him to "convince Mr. Cadion of the opposite" p. 1.

An annotation added in pencil at the top of the page indicates "very understandable", while a note in red at the bottom of the page, connected to the text by an arrow, concludes: "hence technical argument" p. 1. These additions appear to be later reviews or comments, the author of which is not specified.

Context

The 15 H is the version of the Citroën Traction 15 Six sedan equipped at the rear with an oleopneumatic suspension — a full-scale test bench before the arrival of the DS, presented on 6 October 1955. This work is a continuation of the tests conducted by Paul Magès on the 15-Six H ELV 412 on 3 and 5 April 1954. The La Ferté-Vidame test track, owned by Citroën, was used precisely for these in-depth comparisons between vehicles with conventional suspension (springs or torsion bars) and vehicles with hydraulic suspension.

Mr. Cadion, whose name appears here, likely held a position as a test driver or technical manager at Citroën at that time; however, the document does not specify his exact role or department.

Archivist's perspective

This short handwritten note clearly illustrates the empirical development method dear to Paul Magès: convincing through track demonstration rather than calculation alone. It seems that the "head-to-head" described was a direct way of responding to scepticism expressed about the new suspension p. 1.

The annotations in red, added after the fact, suggest a review — probably intended to qualify this test as a strong "technical argument" in favour of the hydraulic solution, in a context where it still had to prove itself against more conventional solutions.

The personal and dated tone ("was not very pleasant for me") gives this page the value of a first-hand account of the internal tensions preceding the launch of the 15 H.