Type approval report for the Citroën ID 19 P (16 April 1957)

In this document

Vehicle identity

This is the official type approval report for the Citroën ID 19 P, vehicle No. 200.001 with engine No. 19 100 018, presented as a production prototype. The findings were made "at the request of the manufacturer, on 20 March 1957" and the document is "Seen and approved" "IN PARIS, on 16 April 1957", registered under No. AA-10657, with the reported signatures of Messrs. Héliot, Flageolet and Pertus p. 2.

General characteristics

The vehicle weighs 1,150 kg in running order for a total authorised laden weight of 1,630 kg p. 1. The engine is a 1,911 cm³ inline 4-cylinder (78x100 bore), compression ratio 7.5, developing 66 hp at 4,500 rpm, for a maximum speed announced as "approximately 155 km/hour" p. 1.

Hydropneumatic suspension

The document precisely describes the system designed by Paul Magès: independent front and rear wheels, each articulated on a "3-head" support resting on a suspension cylinder. The text specifies that "the suspension is of the hydropneumatic type" and that "the pressures of the front wheel suspension system balance automatically; the same applies [...] to the rear wheels" p. 1-2.

The assembly is powered by a reservoir, a single-cylinder high-pressure pump, a hydropneumatic accumulator, a regulator, a pressure distributor and two correctors p. 2. Some key values:

Transmission and braking

The gearbox has 4 forward speeds and 1 reverse, mechanically controlled by a lever under the steering wheel p. 1. The main braking acts on all 4 wheels (discs at the front, drums at the rear) with a maximum deceleration of "7 m/s/s" p. 2.

Annotations and markings

A handwritten annotation in blue felt-tip pen "ID19 57" and "16-04-57" appears at the top of page 1, and a wide orange/red diagonal stripe, appearing to be a sorting or filing mark, crosses both pages p. 1-2.

Context

This type of report corresponds, in France, to the regulatory procedure for the "type approval" of a new vehicle, verifying its compliance with the Highway Code before marketing — here under the authority of the Mines department.

The ID 19, launched in 1957, constitutes the simplified and more affordable version of the famous DS 19 presented to the public on 6 October 1955. It incorporates the essence of Citroën's major innovation — the hydropneumatic suspension, developed by Paul Magès from his plans of 17 February 1944 (Hydropneumatic suspension plans with differential interaction) and tested during the first 2 CV trials of May-July 1946 (Notebook of the first 2 CV trials) then the 15-Six H trial in April 1954 (15-Six H trial) — while distinguishing itself by a less powerful engine and lighter equipment, notably to broaden the range and the clientele.

Archivist's perspective

This document has the value of a founding administrative act: it materialises, on the precise date of 16 April 1957, the official homologation of a system that Paul Magès had developed more than a decade earlier, first for the DS, at the end of a 49-year career at Citroën which he began in August 1925 and ended upon his retirement in September 1974 (Photographs of Paul Magès' retirement). The very detailed technical description of the suspension "3 heads" and the hydropneumatic components p. 1-2 allows one to grasp, in sober regulatory language, the industrial culmination of an invention.

It is part of a larger documentary collection on the development and operation of this system: it can be compared to the Pressure readings of the suspension pneumatic blocks (P 1662), dated from the end of this same year 1957, or the Magès calculation note on the P55 suspension, which extends this work the following year.