Thank you very much for your good and quick reply, Peter. Just aft of the opening canopy, in the roof center, there are vent openings, a loadspeaker and a lamp, and having the antennas here will give only a quite narrow free sector forward (pilot and front seat pass's heads in the way - lots of water in my head!). I see two alternatives: Velcro fitting to the canopy itself a little forward of its aft edge, or making a lightweight, thin "beam" of epoxy and fiberglass extending forward from the roof and under the canopy. I am not permitted to drill any holes anywhere in the aircraft (how I miss my previous homebuilt!), but it should be possible to use the screw holes for the loadspeaker also for this purpose. When there is a will, there is a way ....
Again, thanks vm - also for the link to more antenna info. And: Great-looking trike!
Flarm Mouse: Anyone with any experience?
Best regards, Svein