There are fewer than a dozen gliders (of the ca. 125) operating in the DC area with transponders.
The SSA and SSF strongly recommend the installation of transponders in gliders operating near high traffic areas.
There remains some technical confusion over the value of transponders in gliders in preventing midair collisions.
The SSA’s negotiations with the FAA regarding changes in transponder rules, ongoing for over five years, understandably hit a snag after 9/11, but is still being discussed.