Hi Gary,
We have a Europa XS with a 912S and Airmaster prop and long wings. We were
interested
in two important questions; when will it stop wind milling, and when will
it do an air restart (in case we run the battery dead flying around with the
alternator not charging). We found the stop wind milling speed to be around
50 kts, and the air restart at around 110 kts. These seemed near perfect
speeds,
by our reckoning.
BTW, we got a glide ratio of about 23:1 initially, but got up to almost 26:1 by;
1) adding a cowl flap to the bottom of the cowl (behind the radiators).
2) adding fairings to the non-retractable outrigger legs.
regards,
Terry
________________________________________
From: owner-europa-list-server@matronics.com
[owner-europa-list-server@matronics.com]
on behalf of Gary Leinberger [Gary.Leinberger@millersville.edu]
Sent: Friday, August 16, 2013 11:47 AM
Subject: Europa-List: Re: stopping engine in flight
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 havent 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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