Polar numbers for Discus A

Can anybody tell me the numbers to enter in the Cambridge
302 for the Discus A, or where to find these numbers?
Thanks.

You can review the poplars that are available from WinPilot at
http://winpilot.com/Gliders.htm. Go to the bottom of the page and
select "Polars". This list was created by Carl Herold.

I hope that helps.

Charlie

You can review the poplars that are available from WinPilot at
http://winpilot.com/Gliders.htm. Go to the bottom of the page and
select "Polars". This list was created by Carl Herold.

I hope that helps.

Charlie

This isn't everything you need, but there is a WinPilot polar file you
can get for the Discus A at http://www.winpilot.com/polar.asp.

Unfortunately, different manufacturers like to ask for polars in
different ways. My LX5000 wants the polar's (a,b,c) coefficients and
min and max wing loadings. Cambridge wants (1) best L/D, (2) wing area
in sq meter, (3) best L/D speed in kph, (4) dry weight in kg, (5) speed
at 2 m/s sink in kph, and (6) ballast capacity in liters. You can get
some of that from your glider's manual.

What's the difference between the Discus and the Discus A? SeeYou (my
3.1 version anyway) has polars for "Discus" and "Discus 2". I derived
the C-302 polar numbers by plugging the SeeYou polar numbers for H304CZ
into LXe's Polar tool to get a graph of the polar. From that I read off
the numbers for best L/D speed and speed at 2 m/s sink. I can do that
for you, if "Discus" and "Discus A" have the same polar.

-ted/2NO

Something I forgot to add: the Cambridge 302 utility has a "From File"
button that looks for files of type "Polar Files (*.plr)". Do not
confuse those with WinPilot .plr files, they have completely different
formats.

That's my problem. I can get all these different numbers
but they are not the ones that I need for the Cambridge.
I can get SeeYou polars too.

The Discus or Discus 2 come with 2 different fuselages:
A and B.

Serge Serfaty wrote:
That's my problem. I can get all these different numbers
but they are not the ones that I need for the Cambridge.
I can get SeeYou polars too.

The Discus or Discus 2 come with 2 different fuselages:
A and B.

You may wish to give some consider that any polar coefficient numbers
you obtain are, at best, simply an approximate curve fit to numbers
measured off of one particular clean glider on one particular day, that
flight computers use these approximate numbers to calculate a further
approximation for speed to fly, and that the real world difference in
performance between an A and B model Discus is quite likely smaller than
errors inherent in these approximations. Use some middle of the road B
polar numbers, the result will be close enough to reality of the day to
day performance of your ship...

Marc

Marc
I am totaly aware of that but I don't have these numbers.
Do you know them?

The CAI numbers for the Discus A as per R. Johnson.

Wing loading 32kg/m^2
42.5 @ 98km/h
V 2 163km

You will have to make adjustment for your wing loading
I hope this will help.
Udo





"Serge Serfaty" wrote in message
...
That's my problem. I can get all these different numbers
but they are not the ones that I need for the Cambridge.
I can get SeeYou polars too.

The Discus or Discus 2 come with 2 different fuselages:
A and B.

At 15:00 27 April 2005, Udo Rumpf wrote:
The CAI numbers for the Discus A as per R. Johnson.

Wing loading 32kg/m^2
42.5 @ 98km/h
V 2 163km

You will have to make adjustment for your wing loading
I hope this will help.
Udo


Thanks Udo,
The Cambridge requires the wing area. Do you know that
number by any chance?