If the exhaust pipe wasn't
there the heat would build up and reek havoc.

That depends how smelly the fuel is.

No ENERGY is leaving the exhause pipe

False. This is evidenced by the fact that energy from the exhaust pipe
annoys the neighbors and can be used to drive a turbine. What is closer
to the truth is that the energy leaving through the exhaust pipe is too
much trouble to convert into thrust. (I will note however that the
exhaust pipe actually does add thrust, which often more than offsets the
drag caused by the pipe in the slipstream - I seem to remember 20-80
pounds of thrust from examples in ground school (mumble) years ago.)

Jose
--
I used to make money in the stock market,
now I make money in the basement.
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