ASW20L extentions with winglets?

On Fri, 17 Sep 2004 14:24:32 +0200, "Bert Willing"
wrote:

Well, the ASW20 with 15m and winglets has been measured to 41:1, and I
honestly don't think that an additional meter in span will bring you 3-4
points (the difference between ASW20 15m and 16.6m ist just one point).
Apart from that, I haven't heard of any ASW20L with winglets fitted onto the
extended span, and you probably would have to contact Schleicher to get
their ok.

Performance spread is huge for the ASW-20 - the 20L of my club had
(with 15 meters) at least identical performance as Ventus C and LS-6
(the LS-6 in question was regared as one of the best LS-6 around). We
estimated its L/D to rather 43:1 than 41:1 (based on many team flights
with very good pilots).

It easily outclassed the (re-finished) 20 of our neighbourhood club,
even at high speeds (180-200 kp/h) when the latter carried much more
water (60 Liters vs. no water).

On the other hand: I usually flew the 20 without wingtips. Performance
gain with the 16.60m wingtips was only below 110 kp/h and water
ballast was not possible, therefore in my opinion overall performance
was always better without wingtips, even on weak days (average climb
less than 200 ft/min) - I would not invest a single cent in the
modification of the extended wingtips.





Bye
Andreas