As an older glider pilot with less capacity than when younger I find the solution for me is the external male catheter coonected via a tube to a large, reusable, collection bag intended for strapping to a leg. I have a leakproof,quick-release, connector a few inches from the catheter. This allows me to get 'dressed' well before entering the glider and to connect to the bag when necessary. I can disconnect from the bag before landing. I put the bag on the floor - not strapped to my leg.
Easy to use from a reclining position, discreet, removes all worries about attempting long flights, I can drink as much as I want on a hot day to avoid dehydration without any concerns. No risk of bladder damage in a 'firm' landing. Only once have I filled the bag- but plugging into a spare took only a few moments.
Don't let pee worries spoil or restrict your flying.