On Friday, October 6, 2023 at 6:55:49 AM UTC-7, Dave Nadler wrote:
> An excellently written accident report worth reading:
> https://bea.aero/fileadmin/user_upload/D-KWAY_en.pdf
Extending the prop for an engine start when 850' high and still 9400 ft from the runway is a desperation move. Still, he must have had sink, Schleicher states in the ASH26 manual that an extended prop that isn't turning will reduce glide to 18:1. That is about what I have measured. The lesson here is that you must plan your return to the airport to account for the possibility of sink, no matter the flavor of glider you are flying.

I am perhaps overly conservative, but I'd say extending the prop for a restart at 850' directly over the runway is marginal. At that time you should be entering the pattern for landing (the most dangerous phase of flight) and adding an engine start greatly increases pilot workload. Fiddle with it for a minute, discover it won't start, and now you have <2 minutes left to change your landing plan to account for landing with the engine out, a situation that is likely unfamiliar.

On Friday, October 6, 2023 at 11:59:06 AM UTC-4, jfitch wrote:
> Extending the prop for an engine start when 850' high and still 9400 ft from the runway
> is a desperation move.

Or simply over-confidence that engine will work,
rather than "Plan A is landing" ?
Google map appears to show many decent field options...

Extending the mast at that altitude is sheer lunacy! Just land the
glider and call for a retrieve. Better still, land the glider, attempt
another engine start on the ground. If it starts, motor home.

The Stemme design is such that, even with the nose bowl, cooling inlets,
and cowl flap open, the propeller is still folded and any effect on the
glide is negligible. My decision point for an attempt to start the
engine is 2,000' AGL and, since I'm always within glide of a suitable
airport, if the engine doesn't start, which hasn't happened in 1,000
hours in the glider, I'll land to investigate.

Even with that conservative approach, I could attempt a start on final
approach. But I wouldn't.

Dan
5J

On 10/6/23 09:59, jfitch wrote:
> On Friday, October 6, 2023 at 6:55:49 AM UTC-7, Dave Nadler wrote:
>> An excellently written accident report worth reading:
>> https://bea.aero/fileadmin/user_upload/D-KWAY_en.pdf
> Extending the prop for an engine start when 850' high and still 9400 ft from the runway is a desperation move. Still, he must have had sink, Schleicher states in the ASH26 manual that an extended prop that isn't turning will reduce glide to 18:1. That is about what I have measured. The lesson here is that you must plan your return to the airport to account for the possibility of sink, no matter the flavor of glider you are flying.
>
> I am perhaps overly conservative, but I'd say extending the prop for a restart at 850' directly over the runway is marginal. At that time you should be entering the pattern for landing (the most dangerous phase of flight) and adding an engine start greatly increases pilot workload. Fiddle with it for a minute, discover it won't start, and now you have <2 minutes left to change your landing plan to account for landing with the engine out, a situation that is likely unfamiliar.