P.P.S. I would never ever had stood radially from the turbine. Off to one side is much better. At least he wore goggles. I'd also put a thick plate of steel between it and myself, and watched the engine via a mirror. Looks to me like there was no speed control on it, and a lot of power running through it.

I think Whittle's first test run had the turbine overspeed and suffer a catastrophic unplanned disassembly.