The Jetex motor was a type of solid-fuel rocket motor produced for use as a powerplant for model aircraft. Originally developed in 1947, by Wilmot, Mansour & Company Ltd of Southampton, it was first demonstrated to the modelling press in early 1948, and was available to the public in June 1948, when Aeromodeller magazine featured Jetex power on its front cover. The first motors were the Jetex 100 and 200, with the more powerful Jetex 350 following in November 1948. The most popular motor, the Jetex 50, was introduced in May 1949, along with kits for a model plane and model car using Jetex power.
Jetex motors were powered by a solid pellet of guanidine nitrate, which burnt to release a variety of gases in copious volume, leaving no solid residue or ash. Thrust developed was fairly modest, suitable for horizontally launched flying models rather than vertically launched rockets. The exhaust gas was not excessively hot, which conferred a safety advantage. Fuel and wick to ignite the pellets was manufactured by Imperial Chemical Industries (ICI). The engine casing was made of an aluminium alloy and was reusable, new fuel pellets and ignition wick being a consumable that could be bought and used in the engine.
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