Quote:
Originally posted by Joeaksa
Do not believe that Franklins had hyd valves...
Typical aircraft piston engine turns max 2600-2700. Problem is that the prop is bolted directly to the crankshaft and any faster than that and the tips of the propeller go supersonic. This is not good and causes them to lose lift (thrust) and also it vibrates, causing pieces to eventually fall off, like tips of the prop. This results in an imbalance and then bigger pieces fall off, like the engine, then the plane goes down.
There are a few gear driven engines, with a gear box that allows the engine to run at a higher rpm (more power) while the gearbox allows the prop to remain at slower speeds, but these are few and far between. The Continental GTSIO-520 on the Cessna C-421 is one version of this type of engine.
Joe A
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Was actually talking about jet engine imbalance the other day with my family's Tom Hagen (no other way to explain it) He's an engineer for Qantas, over here from Australia, coordinating setup of newly leased LAX hangars. Day he got here, we went to see Mojave airport. "yea, worked on that one.. that one too.." reading the serial numbers. Top bloke.
Trying to visualize mutiple transonic shockwaves affecting airflow over the wing. Thank you for the new perspective. You owe me ten minutes of life
Would higher performance aircraft, say something like a P-38 or maybe a modern aerobatic plane have to run at even less RPM because of dives, banks and such? or is that where a variable pitch prop comes in? Obviously not on the P-38.
What sort of engine mounting, dampers? solid? would say a DC-3 have in comparison to a high performance prop? wondering just to what level of tolerance is aceptable and what is available?