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ACRO E-mail Archive Thread: [Acro] spinning dogs

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ACRO E-mail Archive Thread: [Acro] spinning dogs


Thread: [Acro] spinning dogs

Message: [Acro] spinning dogs

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From: "David Pilkington" <david.pilkington at>

Date: Sun, 16 Jun 2002 08:17:51 UTC


  The pony express is slow in this part of the world. I often find that
notices of meetings and elections get to me too late. My favourite magazines
arrive long after everyone else has read them. One of my favourite magazines
is Pilot from the UK. An article in the May issue starts with "this article
is going to be controversial, but I think it might save some-one's life."
I'll certainly remember this in case I ever find myself in a Bulldog. It
seems that the Royal Air Force became very cautious about spinning their
Bulldogs after some spinning incidents. The Royal Australian Air Force had
similar problems with their CT-4. Bulldogs and CT-4's have different tail
designs and different spin characteristics, I just meant that both Air
Forces went down the same track.

"I suspect that those involved with test flying modern aircraft simply do
not carry out enough experiments with power on to crack the shell of this
situation. However, I have yet to fly a modern aircraft where the added
benefit of increased rudder authority has been outweighed by adverse
gyroscopic effects in spin recovery."
(The author was writing about spin recovery with power on.)

I agree with the first sentence above. I'd certainly like to see spin test
matrices to verify the second sentence. Seems that there's a lot more that
we can all learn about spinning, especially the different characteristics of
different types plus the effects of rigging changes and repairs in service.
Last week I flew a particular Cessna Aerobat that I rarely get to fly. It's
spinning and snap rolling characteristics were different enough to comment
on. I later noticed that a section of the wing leading edge had been
replaced - looked a very neat job but something must be different. Reminds
me of the other Royal Australian Air Force trainer which had some stalling
problems after the fleet had their wings rebuilt - the Macchi MB326.

Dave Pilkington


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