Long Enough
If you're referring to the power of the engine, it is not in hertz. The power of of a jet engine is measured in pounds.
Well, there are many reasons but the main one is the jet engine is many times larger and more powerful.
jet engine
About 48 hours.
A jet is a type of engine that powers many aircraft and does not have anything to do with airplane size.
More or less than 3 hours (depends on jet engine)
The Thunder Jet was the standard engine in the Cobra. There were 7,675 Cobras made in 1970. I cannot find a breakdown on how man came with the standard Thunder Jet engine and how many came with the Cobra Jet & Super Cobra Jet engines.
Frank Whittle was the invetor of the jet engine.
You can but a mini jet engine on ebay.
Jet engines are not calibrated as such but get routine maintainance depending on the flying hours of the engine. They also undergo major overhaul and preformance runs during their life. But i think calibrate is the wrong term.
I would estimate 21- 25 countries can and do produce jet engines