QDM, you would have to have Mode S, I would in my glider, and so would everyone else from 2008.
It is possible that this would cause so much clutter on ATC screens that it would then be mandatory to switch it off in some areas, like in Holland beneath their TMA. A recent thread on PPrune ATC issues had several ATCO's saying that they could not cope with all GA including gliders etc. squawking.
(On good days, there are more gliders than anything else flying. During one day, it was found that about 350 transits of Didcot power station were made by gliders.)
The thread on the ATC forum I had in mind was called gliders and transponders, and included the following extracts:
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posted 7th October 2002 13:39
In the netherlands gliders are obliged to squawk mode a/c everytime they are flying above 1200 ft. This rule comes into effect by 1-1-2003.
The reason, be-sides european regulations, is to enhance safety and avoid mid-air collisions.
The ironical thing is it is MOST STRICTLY FORBIDDEN to squawk below the schiphol tma........?
[snip]
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posted 7th October 2002 14:53
I am both a controller and a glider pilot from Germany. I donīt like the idea of every glider having to squawk generally at all...from either side. First, there are not many certified transponders available suitable for gliders (they use a lot of electrical power). But most important is the fact that on a nice weekend there ARE already so many targets shown on my screen, that I can hardly see my IFR-traffic. If every glider would have to squawk when flying in controlled airspace I would go mad because I would see even less. [snip]
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posted 8th October 2002 09:33
Completely bonkers idea!
Quite apart from the fact that the SSR clutter on radar would drive us to distraction, the lateral and height envelope of a manouvering glider is so unpredictable it would be of little use to us in atc or a TCAS equipped aircraft.
I don't know about the rest of Europe, but in my experience the UK glider fraternity generally operate to very high standards, keeping us informed well in advance of their intentions/operations, and also generally manage to stay away from similarly busy airports/airfields.
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