Chris Davison wrote:
On the top surface of the wings of a 17m Kestrel I
am looking at, the spar is clearly visible and you
can feel it (it stands out slightly proud) below the
surface of the wing itself. This is uniform down the
whole spar and on both wings.

Is this 'normal'? Will it affect performance??

Thanks
Chris

It happens to some extent to all GRP gliders as they age (some say PIK's are immune - hmmm...), and it's due to shrinkage of the GRP.

It will affect performance because it will trip the laminar flow into turbulent flow, this may or may not be beneficial depending on what part of the polar you are flying on - I think you can safely assume it will adversely affect it.

You will need to get the wing re-profiled to fix it.

Rgds,

Derrick Steed