I have a Tri-Gear 912S Europa. As part of the requirement for my Motor Glid
er 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 d
own 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.) P
lane 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 bet
ter. Should have the long wings done soon (I have given up on estimating co
mpletion 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 t
o start by diving alone although I have heard that a serious dive will fina
lly 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 s
light dive (100 knots) will start to move the blades a bit, and a mere touc
h 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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