Jetex Archive: Motors


		the Classic Jetex archive
			MOTORS

			An overview of Jetex propulsion

This unique powerplant – the Jetex motor – provided the motive power for a highly innovative advance in modelcraft.

On this page we give an overview of the working principle of Jetex propulsion.

On other pages in this section (see linked list to the right), we give details of the full range of Jetex motors, other contemporary Jetex-type motors, and the fuels that powered them all.


What you'll find in the Motors section:

	The genuine Jetex range
	The Jetex rivals
	Operations
	Fuels
	Accessories

How the Jetex motor works

Safety clip spring Threaded hole for attachment bolt Spring plate Wire clip Solid fuel charge Gauze disc Combustion chamber Igniter wick Jet orifice Back plate Asbestos washer End cap		The burning of the solid fuel charge (5), once ignited by the wick (8), generates a large quantity of gas in the combustion chamber (7). This is forced out the jet orifice (9) at great speed, producing (by Newton's third law of motion) a reaction which drives the motor in the opposite direction. The springs (1) are intended to hold the end cap (12) tightly seated on the asbestos washer (11) so as to seal the combustion chamber (7). They are seated on the spring plate (3) and act through the clips (4) to provide a safety release mechanism in the event of the orifice becoming clogged. The gauze disc (6) serves to hold the coiled wick tightly against the fuel charge, while the back plate (10) protects the washer.

Acknowledgements

Illustration sources:
- Cutaway drawing adapted from Jetex 200 instruction sheet, Wilmot Mansour and Co. Ltd., 1948
Information sources:
- "Jetex!" by Kenneth Brothwell, SAM 35 Yearbook #3, Dec. 1984 (Bill Henderson)
- "Engine Analysis No. 15 (New Series)" by Ron Warring, Aeromodeller Nov. 1953, Jan. 1954 (Derick England)
- Additional personal knowledge from Bruce Ogden and Bill Henderson

Queries? Corrections? Additions? .