AD&D 2e sourcebook TSR 9388, The Shining South, spends about three quarters of a page to describe Halruaan Skyships as "magical items".
The standard skyship is mentioned to be three-masted, with a broad beam to allow it to rest easily on the ground. The weight they can carry depends on the altitude, they cannot carry their own weight above 3600 feet. At an altitude of about 100 feet, they can carry 10 to 15 tons of cargo, a rather small amount as compared to equivalent sea-going vessels. They run at the mercy of the winds, presumably just like normal sailing ships. Additionally they have a special magical rod that allow control of the levitation fields of the ship to get it rise or dive at a rate of 120' per round. They offer no steady fighting platforms, though wizards are able to cast spells from its deck. In aerial combat, they have maneuverability class E.