[RPG] How large is an airship? (Dimensions) How much room does one have below decks?


My players are getting an airship and I was wondering if they would be able to mod it in various ways, like adding a brig or expanding the storage. I was wondering how much room they would have to build onto it.

Best Answer

The only information available to us in D&D 5E about Airships comes from the DMG and an entry in

Storm King's Thunder.

They are mentioned as existing in other adventure modules, but the only thing like stats comes from a single line on DMG 119, and

SKT 133-135.

The DMG gives you the functional stats of the airship, but nothing in the way of dimensions. The only sort-of useful information it provides here is the crew compliment, the max number of passengers, and how much cargo it can carry. 10 Crewmen, 20 Passengers, 1 ton of cargo. The exact dimensions are unknown...because we don't know how much space is dedicated to each crewman, how much space is dedicated to each passenger, how much space is dedicated to the operation of the ship, and so on.

SKT features a much smaller airship (Crew of 2, ~6 passengers). It also includes a map that could be a good reference for you, and descriptions of how the ship works.

From this point on...you're in purely homebrew territory. I can point you in a direction that would potentially be helpful...but I cannot offer you a concrete answer, because no such answer exists.

So, you have two options here, as far as I can say.

Simple: You know the ship can carry 20 passengers...so allow your players to 'secure' some of the passenger cabins to serve as a brig. This is the simplest way to do it, and can be handled by having them shell out some money to reinforce the walls, and replace the door with a sturdy one that locks. Alternately, they could sacrifice their cargo capacity to put manacles down in the cargo hold and use that as a brig. This is the easy way that doesn't require a lot of work on your part.

Detailed: The best reference I can aim you at for truly homebrewing up an airship is the 3.5E Conversion of the Spelljammer ship creation rules. Obviously, this isn't going to be perfect, because a Spelljammer flies according to very different rules than a normal airship. But...the rules for determining how large it is, how much stuff you can put inside of it, etc...those are very helpful.

An important thing to bear in mind...in this document 'Tonnage' is NOT representative of a physical ton of weight or of a ton of cargo. It is a ship-scale reference for size that represents a cube measuring 1,350 cubic feet. Assuming a 9-foot ceiling, that means 1 'Ton' of ship is 30 5x5 squares. Again, this is NOT a perfect answer, but it is the only pre-made homebrew tool I have found that fills out that level of detail aboard a ship, if you so desire.

The pdf for these rules can be found here: http://lost.spelljammer.org/TBLIV/lsccs3e/3eShipConstruction.pdf

Thanks to suggestion from nitsua60. I would like to point out that while converting 3.5 content to 5e is generally something of a nightmare, I have found this particular conversion to be quite simple. That fan-made Ship Construction guide is better organized than the original AD&D Spelljammer construction guide, and is simple and straight forward to work with.