Wendell Voto wrote:

Also, I have noticed prop tips with little hooked ends, whats the deal,

who makes them and are they documented to be effective?

...Chrissi

Could this be the P-Tip props by Prince Aircraft Company? They are supposed
to reduce tip vortices, they are available from Spruce Aircraft.
Wendell

He copied them from Hartzell (IIRC).  They made (make?) a "Q-Tip" prop with
winglets (Long EZ talk) for certified applications.  I believe they only
claim lower noise, but that noise takes energy . . .    I'd imagine the
improvements
are small or they'd all be like that.

I heard a story about a relatively new FAA inspector that saw one of these
Q-Tip equipped twins in a hangar, and was looking at the tips closely when
the owner walked up.  The FAA guy said something about the tips hitting
something, the owner thought he was joking and said something like, "We just
smoothed them out a bit and repainted them after that gear up landing, who'll
ever know".  The FAA guy whipped out his ID, and said "I'll have to ground
this aircraft and write you up for a violation".  The owner, still thinking
it was
a joke, says, "Why, heck, you wouldn't violate me for just a 1/4" of bent tips,
would you" with a mock hurt look on his face.  As the FAA man started
filling out the paperwork for the citation, the owner finally figured out
that he
had a real turnip on his hands and tried to REALLY explain.  The FAA man
was having none of it.

When the FAA guy got back to the office, he started telling his friends of this
yay-hoo he ran across today that had tried to get away with repainting props
on his twin with bent over tips.  "Even said they were supposed to be that way
once he saw I was from the FAA, but he didn't fool me."   A long silence from
the older heads in the FAA office, and a few snickers.   They had to send
a different FAA rep back out to apologize to the owner, since the original
guy was at a training course.  I heard this standing next to "the airplane", but
not from the owner, but a friend of his.  Might even be true!

Bill Freeman

Long EZ builder & pilot
BSME, MSME
EAA Technical Counselor

 
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