Gary, Do you have a prop windmilling figure to compare it
with? Regards, David Joyce, G- XSDJ
Gary Leinberger <Gary.Leinberger@millersville.edu>
wrote:
> I have a Tri-Gear 912S Europa. As part of the
>requirement for my Motor Glider endorsement (US) I had to
>feather the prop, stop the engine and do some gliding. I
>have a three bladed Airmaster Prop with the feather
>option. With the short wings and the engine off, prop
>feathered, I show about 600 fpm down with no thermal
>activity. (I was at about 6000 feet, above the tops of
>the cumulus clouds in the area so I haven't tried this in
>a thermal yet.) Plane is a bit heavy (full IFR) and I am
>a proper sized American - 265 lbs. And I had an
>instructor on board. So a lighter plane (and pilot) may
>do better. Should have the long wings done soon (I have
>given up on estimating completion dates) and will provide
>some better info on soaring then.
> The 912S is a high compression engine, unlike the 912
>and 914. So the prop will stop when the ignition is off
>even if not feathered. It is also hard to start by diving
>alone although I have heard that a serious dive will
>finally get the prop wind-milling high enough for a start
>- I think you need at least 300 + rpm to get a charge
>out of the ignition system. For mine a slight dive (100
>knots) will start to move the blades a bit, and a mere
>touch of the starter lights it off.
> The feathering and un-feathering takes a bit of time -
>which I imagine will seem even longer if you wait too
>long when running out of lift.
> Gary Leinberger
> Lancaster, Pa.
> N388SG
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