by Annie Berrisford, March 2009

Have you ever wondered how to start a jet engine? Unfortunately, it’s not as easy as turning a key and expecting it to burst into life! We need one of these …

Image above: The AerMacchi Air Start Cart. Photo courtesy of Rolls-Royce.

This is called an “air start cart” and it provides compressed air to the jet engine at sufficient flow and pressure to turn the jet at high enough rpm to start the engine. This will mean that we do not need an on board system to start the jet engine, saving us valuable space and weight.

The air start cart that is currently used to start the Eurofighter’s EJ200 engines is manufactured by AerMacchi – this delivers air at a pressure of up to 4 bar abs. (58 lbs / sq in) and a maximum flow rate of 1.25 kg/s (165 lbs / min). It is powered by its own on board generator.

We are planning to run the engine in BLOODHOUND SSC on a UK runway for initial testing in the first half of next year, so we will need to have sourced an air start cart by then – but we will eventually need two! To gain an official land speed record, we will need to complete the out run, turn the car and return through the measured mile within one hour.

With such a complex car, we need the turn around to be as simple as possible. In order to achieve this, we need two start carts - one for each end of the track. Having two carts also means that we have a back-up; if in the unfortunate event of one start cart failing, we would still be able to run the car!

We are extremely fortunate to have a number of companies helping us track down the air start units that we need. The search continues……………

Image right: The Eurofighter and an airstart cart waiting to be connected to start the engine. Photograph: Chris Globe.