LEX (sounding rocket)
LEX was a French experimental hybrid-propellant sounding rocket, developed by ONERA. It had the objective of testing a lithergol fueled rocket engine. It was the first rocket in history to use this technology, flying 8 times between 1964 and 1967.
The rocket had a single stage with a thrust of 10.00 kN, a gross mass of 100 kg, a height of 3.40 m, and a diameter of 0.16 m, reaching an apogee of 115 km.
Launches
All LEX launches were carried out from CERES Ile du Levant.The first LEX-01 launch on 25 April 1964 was a partial success, with the payload consisting of a telemetry transmitter.
Three LEX-02 rockets were fired on 1 June 1965. One of these rockets, with an initial mass of 78 kg, reached an altitude of 68 km.
Four LEX-02-B launches occurred on 1 November 1967. Two were intended as technological tests and two others as actual payload launches. These carried the SECT Meteo meteorological payloads, reaching an altitude of more than 100 km, with a parachute ensuring a correct descent for 31 minutes allowing wind measurements over a wide range of altitudes.
| Flight no. | Version | Launch date | Payload | Apogee | Notes |
| 1 | LEX-01 | 25 April 1964 | Telemetry transmitter | 1 km | First flight of LEX |
| 2 | LEX-02 | June 1965 | Telemetry transmitter | 68 km | First flight of LEX-02 |
| 3 | LEX-02 | June 1965 | Telemetry transmitter | 60 km | |
| 4 | LEX-02 | June 1965 | Telemetry transmitter | 60 km | Last flight of LEX-02 |
| 5 | LEX-02B | November 1967 | Telemetry transmitter | 101 km | First flight of LEX-02B |
| 6 | LEX-02B | November 1967 | SECT Meteo | 80 km | |
| 7 | LEX-02B | November 1967 | SECT Meteo | 115 km | |
| 8 | LEX-02B | November 1967 | SECT Meteo | 115 km | LEX's last flight |