Tony, The other side of this particular coin is slowing down when you reach
you paddock. No doubt everyone with any sort of VP prop has noticed what an
extraordinary difference it makes to your ability to slow down and get onto
the ground whether your prop is fully fine or fully coarse. Landing with a
feathered prop must be a bit like landing a glider without airbrakes -
liable to make a large hole in the far fence of the paddock! I am not
against feathering props but would be hesitant to use one in almost any case
of engine failure in this country where you are lucky to find a field 400
yds long. Regards, David
----- Original Message -----
From: Tony S. Krzyzewski <tonyk@kaon.co.nz>
Subject: [Flying] Best Glide
>
> Yesterday we did some glide testing on ZK-UBD and ended up with some
> rather interesting results. Remember that ZK-UBD is a Classic monowheel,
> has no fairings, and that all the tests were being performed at MAUW.
> We were able to repeatedly show that the rate of descent improved by
> around 90% when we feathered the prop compared with the engine just
> idling across a wide range of speeds. On ZK-UDB we ended up with a best
> glide speed of 70 knots IAS at 520fpm with the prop feathered. With the
> engine idling the rate of descent at 70kias was 1100 fpm.
>
> For those with Airmaster featherable controllers this is worth
> remembering if you ever have an engine failure. It may mean the
> difference between reaching that paddock and not reaching it!
>
> Tony
>
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