Andy,

I had the same relief tube problem in my LS8 in flight. Decided to
unlock and lift the canopy slightly to free the tube. You release both
the forward and rear canopy locks with the same handle in my glider,
one on each side. As you found out, I had to push considerably hard to
get the canopy off the rails. Then, I needed a third hand to yank on
the pee tube (and another one to keep the glider from porpoising). Pee
tube clear and un-kinked is now on my check list.
Regarding the subject at hand: my transponder antenna is on the glare
shield and has the pull-apart connector on the cable that has been
discussed here. I also have a seperate ground cable from the aluminum
ground plane under the glare shield to the glider metal structure that
seems to have improved my transponder operation.

Herb, J7

Andy wrote:
Make sure you can jettison your
canopy and bail out easily.

And don't expect the canopy to fly off when you pull the handles. I
had reason to open the rear latches of my ASW28 in flight. I expected
to have to pull down hard to keep the canopy from rising. Instead I
had to push up firmly to release my relief tube from under the
instrument panel.

I don't want to find out what happens if the forward attach points are
also released but I'm expecting to have to push hard to make the canopy
depart.

Andy