Hi Gerry
Just a note on the forced landing. Anyone who is trying to fly with a
prop that has the ability to truly free windmill better be prepared to
count on performance comparable to having a drogue chute in trail with a
dead engine. If I were to have a sub setup like this, practice with a
stopped (not idling engine) engine would be on my agenda. I met a piper
Archer II who walked with a severe limp because one leg was several
inches shorter than the other. He was giving a very capable instrument
student a last lesson before he took his instrument check ride. Perfect
day, long runway, 10MPH right down the runway, clear and very wide
runway. several hundred feet over the runway with plenty left, the engine
quit. The next thing they both knew they were in a mass of twisted metal
on the grass off to the side of the runway? Everyone was having a very
hard time figuring out what happened? It ends up the catastrophic engine
failure was a broken crankshaft just aft of the main bearing for the
prop. This allowed the prop to really spin up without any frictional and
other drag from the motor. DRAG CITY! This is not something one could
easy practice. They remembered having the nose pointed down a lot further
than normal but things went bad anyway. Just to send this message home,
the next time you have access to a pinwheel, stick it out car window with
30MPH airspeed and prevent from turning and note drag, then let it spin
up WOW. Stuff happens, but if you have this one built in you can somewhat
prepare. I don't know if anyone still offers a power plant with free
windmilling prop?
Ron Parigoris
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