The Zander flight computer performs a constant L/D calculations throughout a
flight. The L/D is presented numerically on the screen. All you need to do
is note the L/D, flap setting and speed at any particular time.

David
"Mark Zivley" wrote in message
m...
We all know what the manufacturer's polars look like, but what about our
individual planes. Has anyone done any work to develop a program that
would look at some flight logs and determine what a particular glider's
actual polar is? At one point Ball was making a vario system that would
determine the aircraft's polar over time just by flying.

For someone who already had some algorithms for computing wind from ground
track drift during thermals could take this info and then be able to back
figure from GPS ground speed what the IAS was during a particular phase of
the flight. By isolating longer sections of cruise flight at varios
airspeeds it should be do-able. Question is, has it been done.

Mark

extra "hot" in the address to delay the spammers...