"W.J. \(Bill\) Dean \(U.K.\)." wrote in
:

Fitting a transponder
would do hardly anything to reduce collision risk for most gliding in the
UK. It will only help those who can and want to fly high in wave.

I note that there are moves to have unmanned aircraft (UAVs)
flying in UK airspace, e.g.
http://news.bbc.co.uk/2/hi/business/5198364.stm

The current rules and procedures presume that all
aircraft contain functioning eyeballs and brains
that can look out the window. If they don't then
the rules and procedures have to be rethought.

Anybody see a connection with mandatory transponders?