Bombard

(https://www.dndbeyond.com/sources/sais/aag/astral-adventuring#Bombard)
Bombards are built by giff. The major feature of each ship is an enormous cannon that fires massive cannon balls capable of blowing other ships to smithereens. (The cannon is included in the cost of the ship.) A bombard can carry up to fourteen giant cannon balls, each of which weighs 10 tons. These cannon balls make up most of the weight of the ship’s cargo. A winch mounted on the aft deck is used to load the cannon balls on board.
A bombard can float and sail on water, but it can’t land safely on the ground (its keel would cause it to roll on its side).

Armor Class: 15 (wood)	Cargo: 150 tons
Hit Points: 300	Crew: 12
Damage Threshold: 20	Keel/Beam: 140 ft./30 ft.
Speed: fly 35 ft. (4 mph)	Cost: 50,000 gp

Weapons & Armament

2 Ballistae (Crew: 3 Each)
Armor Class: 15
Hit Points: 50
Cost: 50 gp (ballista), 5 gp (bolt)
It takes 1 action to load a ballista, 1 action to aim it, and 1 action to fire it.
Bolt. Ranged Weapon Attack: +6 to hit, range 120/480 ft., one target. Hit: 16 (3d10) piercing damage.
Giant Cannon (Crew: 4)
Armor Class: 19
Hit Points: 250
Cost: — (cannon), 1,000 gp (giant cannon ball)
It takes 3 actions to load the enormous cannon and 1 action to fire it.
Cannon Ball. Ranged Weapon Attack: +6 to hit, range 600/2,400 ft., one target. Hit: 88 (16d10) bludgeoning damage.