With most commercial aircrafts using turbofan engines which makes it faster. Why do a portion of military planes still uses propeller engines? I think the C-130 is the best example.
In: Engineering
Those propeller aircraft still have jet engines, they are just connected to a propeller instead of a ducted fan. That gives them different trade-offs, propellers (turboprops) are slower but have better efficiency.
A new type of engine we might see in the next decade or so is an unducted fan engine like the CFM Rise, which aims to combine the efficiency of a turboprop with the speed of a turbofan.
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