On Tuesday, October 17, 2017 at 9:00:58 AM UTC-7, jfitch wrote:
On Tuesday, October 17, 2017 at 5:54:29 AM UTC-7, Nik wrote:
Hi all,

I recently bought an ASH25M, which still got the Technoflug prop. Now many PPL advice to go for the AS prop. I asked Schleicher and Rolf went like: "At least we can repair it, if it has a crack or so." - But I could not manage to get information about performance.

Anyone switched to the AS prop? Is there some worth mentioning difference in performance? Like aceelartion or climb rate? What about weight difference?

Thanks in advance for any hint, Nik

p.s.: If anyone is looking for an ASW27, I just got one too much

I do not have numbers for you. The reason for the change to the AS prop was supposed to be for acceleration, particularly operating off grass runways, not climb rate performance. Comparing climb rates on the ASH26 between Technoflug and AS there does not seem to be a lot of difference. I changed the engine (to injected) and prop together in a 26, and got a substantial improvement in climb performance (about 25%). I cannot say how much is due to the engine and how much the prop. The AS prop is heavier (it says this in the TN) and when you change it you must also change the lower drive cog and guide (27T replacing 26T) as the ratio is different. This makes the belt tighter so you hope there is enough adjustment left in the screws, otherwise the arms must be changed as well. It is not a simple bolt on.

The engine bay doors may need adjustment over the root of the blades for the AS prop to fit.
My only experience is flying the same ASH25, as an M then an Mi. The better climb is probably more from the horsepower improvement, but if I remember correctly that happens at a slightly higher RPM than the non-injected engine, and the AS prop will turn faster.
It's been years since comparing the two.
Jim