Requiring that flarm is in the stealth mode during contests doesn't
accomplish the goal of preventing pilots from seeing each other
thermal strengths. This is because it is easy to calculate it in a PDA
using just the GPS data from the flarm. It's just a matter of time
before this is implemented in existing PDA software (some of it is
already done in LK8000). And then what? Do we disallow certain PDA
software? Is this the way we want to go?

It is certainly possible to have a PDA software that would keep track
of all the competitors, their start times, average speeds, their
estimated MacCready settings, etc. And there seems to be nothing in
Flarm to stop that. The only thing that can reduce the usefullness of
this type of software is to reduce the flarm range to only the minimum
needed for safety. Unfortunately, PowerFlarm seems to have an
increased range over the regular flarm used in Europe.

Wiktor Kozlik