Passenger in a friend's C140, night flight into Springbank (CYBW), radio failed before we entered the zone, but nav lights on.
We joined downwind, no other traffic, no green light on final, so my friend went around. Next time, still no light so we landed, taxied to the tower and talked to the controller. "Sorry about that. We haven't used the light for such a long time. It fell apart when I picked it up!"