And another thing:

Regarding starting the JS1 jet at altitude - I found that the jet was unreliable in low temperatures in the UK on ordinary diesel fuel but worked fine on Jet A1. In South Africa with a ground level of 4500 and high temperatures mine was very reluctant to start on Jet A1 at any altitude in flight. The JS factory suggested I use synthetic (gas to oil) premium diesel like Shell V Power Nitro diesel and my jet loved it in both climates. Started first time up to 9500 asl which was the highest I tested it and never failed to start on it.