ASW-27: Problems with aileron stick forces

Gentlemen,

we have a problem with our ASW-27:

When moving the aileron, it feels as if the stick has to overcome catches - you feel a resistance that you need to overcome with significant force. Three catches when you apply right aileron, five when applying left aileron.

The problem has been existent for the last three years - but last week it got bad enough to ground our ASW-27.

Schleicher says that this problem is unknown for the ASW-27 - but today we found out that a club on our neigbour airfield has the same problem with their ASW-27.

It looks as if the source of the problem is located within the wing. Impossible to find without having to open the wing.

Did this problem occur with any 27 that you know of?

Bye

How old is it? Had a similair problem with an old ASW 20. 20 year old glider but had only 950 hrs total time. It turned out to be the pushrod roller bearing guides in the wings themselves. They either wear little grooves and ridges in the painted surface of the pushrod or flats develop in the plastic bearings.

Paul

Hi Andreas.

I had a very similar problem on my '27 after about five years. I took it to the Schleicher agent and he spent a while returning all the control deflections etc. to their factory settings, and there has been no problem since.

I think someone I lent the glider for a comp. had tried to adjust a perceived aileron imbalance but didn't realise the complex interaction of all the control run settings...

I have come across other Schleicher gliders that required a gentle sanding of the gaps between the flaps/inboard ailerons/outboard ailerons, as they were causing 'notchiness' (ASH25 mostly).

Regards,

Hi Edward,

wrote:

I see.

Let me guess - your outer ailerons are not symmetric when the stick is centered?

Indeed - this is what Schleicher told me, too. Unfortunately this is not the case on our 27...

Thx for your input!

Bye