The propeller of a anti-submarine warfare airplane the EP-3E Orion . Note the blade's attack angles are variable, and in this case turned flat.
The propellers of a cargo aircraft
Hercules .
Note the blade's attack angle are variable, and in this case turned very sharp.
A contra-rotating propellers of a modified P-51 Mustang fitted with a Rolls-Royce Griffon. Photo by Eric Gideon.
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