Changed the wording on these, think they might be better.
Ability: This equipment may be used on an island o on a ship. If used on a ship; she gains one 4L cannon that can shoot from any mast (even an eliminated mast). If the cannon roll is a 1, turn this equipment face-down. You may give this ship a repair action to turn it face-up again instead of repairing a mast. If used on an island, this equipment becomes a 3L+L cannon that can only fire from one point on the island. To fire a catapult on an island, a friendly crew must be present on the same island; if the roll is a 1, turn the catapult equipment face-down and remove the associated crew from the game. Catapult must be loaded back onto a ship to be tuned face-up again.
Ability: This ship gains 3L cannons equal to the number of masts this ship had when constructed. Ballista may fire from any mast (even an eliminated one). If any Ballista roll is a 1, eliminate a crew from this ship. If all Ballista rolls are 1, remove Ballista from the game.