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I asked this question to my CFI, but he just give me a blank stare, so
I'm hoping someone here could answer it. As I understand it, all commercial maneuvers revolve around the idea of converting between potential energy and kinetic energy, and the control characteristics of the plane assiciated with these conversions. Think about a lazy eight without the turn, to keep it simple. You're just keeping a constant power setting and climbing then descending. Before you start the climb you are cruising at 100 knots at 3000ft. High kinetic energy, (relatively) low potential energy. At the top of the climb you are now at 60 knots (low kinetic energy) and 3600 ft (high potential energy). Now if you were to let go of the controls, the plane will naturally nose down (if you trimmed it right) and level back off at 3000 ft, and at the starting airspeed of 100 kts too. The reason for this is the laws of thermodynamics. Energy converted back and forth always equals the same in the end, with a small loss due to entropy. Now with that all said, imagine how a constant speed prop will perform diffrently than a constant pitch prop. I don't know much about constant speed props much since I've never flown one. When your airspeed decreases in a constant pitch prop, engine RPM decreases, therefore horepower decreases, right? But in a constant speed prop, the prop governer will decrease the blade AOA, keeping the engine RPM the same, but will horsepower remain the same? Would this result in less total energy lost across the airspeed changes, therefore making it easier to do commercial maneuvers? |
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