cjcampbell writes:

The reason we use jet engines is that they are inherently more powerful
and they can operate at high altitudes where the efficiency penalty
compared to piston engines is less. At high speeds, drag is a more
important factor in fuel economy than engine efficiency, so jet
airliners get their best fuel economy at high altitude. But for short
hauls where it would just be a waste of fuel to climb to high altitude
and descend again, a turboprop will deliver more power than a piston
engine with greater fuel economy than a jet.

There are still the questions of simplicity and reliability, which I
thought were both higher for gas turbines. They are certainly more
reliable; and I should think they'd be simpler, too.

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