On Apr 2, 11:34*am, 77 wrote:
Am going to fly a club K21 in the upcoming contest at CCSC and have
been trying to find some basic speed to fly data.

What I have so far is Schleicher says( in an on-line brochure) that
the L/D flown two up is 34 at 90 KMH...so I interpret that to be about
49 Kts.

They also say that the stall speed flown two up is 35 Kts

I find no mention anyplace of Minimum Sink Speed. From the polar in
the brochure it looks to be about 42 to 44Kts.

I have a some cross country time in the K21 and these speeds look
reasonable to me but I'm not sure.

Anyone have any suggestions regarding speeds to fly the ASK21 ?

From the above data on a weak day I might *fly 55 kts or so. On a good
day with *cu's maybe 60 or even 65 kts. Any rules of thumb you would
like to share ?

Thanks,

Jim

Jim,

Pull out Reichmann and start building a speed to fly chart. It
should have speed to fly based on each 0.5 to 1 knot of thermal
average based on what your conditions are. That will give you a
target speed to fly.

If you would like, send me note and I can send you several of the
programs I use. Below is the chart I use for a Ventus. It is all
based off the polar of the glider you are flying.



MC MPH knots Avg Cruise Speed (MPH)
0 63 55 0
1 75 65 28
2 85 73 41
3 93 81 50
4 101 88 57
5 109 95 63
6 116 101 68
7 122 106 72
8 129 112 76
9 135 117 80
10 140 122 83