There is something that has been puzling me for a while.
Many people on this group suggest one CS propeller system vs the other based on
weight, cost and increased performance yet not once have I seen anyone ask about
what testing programme has been run with that particular prop on the Europa.
A few years ago I was priveleged enough to be the (unpaid) test pilot for
Airmaster.
Airmaster, when they were ready to go into production, went out and bought
a Europa with a fixed pitch prop, fitted a US$5000 in flight data recorder
and I then spent 30 hours flying the plane in just about every flight
configuration
you could imagine.
While this was going on Airmaster were having their hub tested at Auckland
University
to determine the blade pull out forces (I believe they gave up at 28,000lbs)
and analysing the hamonics of the system.
They then fitted the Airmaster CS prop to the aircraft and I repeated the flight
test process... right up to doing rapid throttle backoffs while flying the
aircraft
at 185 knots with a harmonic analyser strapped to the engine at the insistance
of the PFA and thoroughly exploring the climb rate under all fail conditions
so that a go around is actually possible in all conditions. While flying
at that speed is something that I am unlikely to repeat and wouldn't recommend
except under strictly controlled test flight conditions, flying the Europa
at 185 knots in a steady dive from 10000 feet is the closest I can imagine to
flying a jet fighter.
Doing this test flying gave me a real respect of how good a job Europa did with
the design of this aircraft and how much work goes into the design,
implementation
and testing of a propeller system that I'd be happy to fly behind in all
situations.
When you are considering a propeller system that is an alternative to the one
that
Europa recommend can I suggest that you ask for their test data and ask them
what flight test programme they have flown on the Europa. If that can't be
provided then you need to assume that you are going to be the test pilot.
As to performance of a Europa fitted with a CS prop... in 2002 I made a flight
with the data recorder running and peaked at 149KIAS/ 151KTAS at 1500 feet
straight
and level... this with a 912 powered Europa and Airmaster propeller fitted.
After this flight I came to the conclusion that the aircraft flies far batter
with the CofG as far aft as practical and now, when I am doing high speed
run testing always shift the CofG aft.
Regards
Tony
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