I don't recall seeing this mentioned here but apparently Flarms are
now available in the US.
See discussion on Williams Forum:
http://www.soaringnet.com/forum/viewtopic.php?t=2404

From Rex Mayes:

We would like to examine the level of interest in using FLARM in
gliders flying at WSC to improve safety with collision avoidance
technology.

Learn about FLARM.

http://www.flarm.org/index_en.html

Flarm is being introduced to the US market this Summer. It is an $800
alternative to a $3000+ transponder/ PCAS system.

The downside is that Flarm will only interact with other flarm units.
It will not see tansponder signals. Tcas and Pcas will not see Flarm
so it does not solve Glider/ GA or Glider/ airliner conflicts.

Flarm does however help with the more likely event of Glider to Glider
mid air potential in gaggle flying or ridge soaring on the Whites and
the great convergence of the Mendos.

Flarm also offers the ability to see what other gliders are doing. It
will locate a glider and indicate that gliders rate of climb. Thus
possibly reducing the need to query another pilot on the radio as
often.

Flarm also has IGC approved flight recording capability.

We have been following the development of FLARM since our visit to the
AERO in 2005. Since then, it has become mandatory in several countries
and in many others, it is widely used and encouraged. We think it is
time for all glider pilots to consider their traffic collision
exposure and what they are doing to mitigate it.

We are not convinced that FLARM is the answer but we are considering
installing FLARM in the WSC Fleet including towplanes.

It only makes sense to install FLARM if everybody does it.

Please take time to learn about FLARM and let WSC know your opinion
either on this forum or privately to .

We are very interested in hearing from every pilot who flies in this
region.

Thanks for reading this and for your careful consideration.

Rex Mayes and the Staff at Williams Soaring Center