A Winghy is a Dinghy with a Wing that flies like a kite instead of a conventional sail
Winghies work in basically the same way as Manafariba, so if you’ve not read that page yet, read it now.
Hopefully, if you’ve understood how Manafariba works, the diagrams explain all.
Apart from the fact that a winghy has only one sail and one keel, instead of many of each, the other big difference is that the sail is a wing, a proper aerofoil, shaped just like a long, narrow wing of an aeroplane – or, if you’re familiar with gliders, more like the wing of a glider, because the speed of this sail relative to the air is closer to the speed of a glider than that of a powered plane.
The wing is constructed like early aircraft in the real world: a light wooden framework with fabric (in the case of winghies, usually silk) stretched over its surface and glued to the frame. (See Aircraft Dope in Wikipedia for a bit about this, and a picture.)
Winghies are rich men’s toys. Very high performance, but an expensive hobby. The wings are very easily broken: it takes a real expert to avoid ditching them occasionally, and they’re not robust enough to survive it. Winghies generally carry at least one shorter spare wing in the hull. Wingsmiths make a good living.
Ditching sails on Manafa line ships is annoying, but they just need to be dried out and they’re fine. The professional flyers who fly them rarely ditch them anyway, except during their training. They’re usable wet – after all, the ship keeps sailing in the rain, too – but they’re better dry.