How do ships?

I am now deeply into the weeds writing a game set onboard a ship, with a crew of NPCs who move around performing their duties as the player sneaks around and tries to solve a murder to clear their name. So far so good. Just one problem.

I know very little about ships.

The setting is specifically a retrofuturistic zeppelin (think steampunk aesthetic), so I can take a lot of artistic liberties for the sake of the story and the gameplay. But I also know we have both mariners and naval historians here who might have useful insights, as well as being interested in IF. So this seems like a good place to solicit feedback, and see if I’m crossing the line from “artistic liberties” to “ruins my suspension of disbelief through lack of research”.

The ship has two decks, each approximately six rooms long and four rooms wide in parser IF terms. The lower deck is divided between cargo storage in the aft part, and the boilers in the fore part. The gunner, cook, and two engineers each have a bit of space down here, and walkways on the outside allow for maintenance to the hull. (This seems more practical for an airship than for a normal, seafaring ship.)

The upper deck is simpler and less maze-like. At the fore end is the bridge and helm; at the aft end is various instrumentation for navigation and weather observation. A cabin on the port side is dedicated to the captain and a cabin on the starboard side to the first mate-slash-medic.

In between the two decks is a low crawlspace where some of the machinery can be accessed, and also illegal goods can be stored, if this ship were ever doing any illegal smuggling, which of course it isn’t, that would be illegal.

The ship is currently flying with a skeleton crew of six, due to some unforeseen circumstances around the launch (read: law enforcement was about to get involved). As a result, everyone has their specialties, but they also generally do everything else as needed:

  • Shimat, the captain, pilot, and helmsman
  • Kasap, the first mate, navigator, and medic
  • Ishme and Bashti, two engineers who keep the ship functional
  • Qarrad, the gunner, who deals with threats to the ship (prevalent in the setting) and takes care of the cargo
  • Udan, the cook, who keeps the crew happy and also takes care of the cargo (and passengers if there are any)

Some parts of the design are distinctly backwards from a normal ship, by design—the lower deck being larger than the upper one, for example, because there’s no longer any issues of volume below the water line vs volume above it. Other parts ended up backward mostly by complete accident, like the boilers and helm being at the front, and those can easily get flipped around if needed; those are just a consequence of putting the engineers’ quarters far away from the rudder access for puzzle reasons.

But most of all, I’m wondering if there’s anything about this—the design of the ship or the makeup of the crew—that just makes no sense to someone who’s used to sailing. Are there important things that have been left out and should be included, or at least explained away? Are there things that don’t make sense and should be cut (or explained away)? The design of the ship seems like an important part of this story, so I want to do it right—or at least right enough that people who know ships don’t spend the entire game saying “that’s nonsensical”.


An Executive Officer is typically second in command on a military vessel.

The Chief Engineer is generally second in command on a commercial vessel.


I know only that the cabins under a zeppelin are ridicously small compared to the “balloon” (which is actually not called balloon afaik). So your rooms are too many I guess, or it is a really big zeppelin.

Edit: Now I think you were thinking about a big zeppelin in the first place, so no need to shrink the cabin. And in a Steampunk setting you can come up with a solution for everything. Just add steam power or ether or magic or…


Do you happen to know what it is called? I feel like it should have a different name but I haven’t been able to find it online.

And yeah, it’s bigger than a real-life zeppelin probably should be; some amount of fictional technology is needed to make airships actually a useful way of transporting cargo compared to land or water. So that’s something I’m comfortable handwaving for the sake of the setting.


Ooh, interesting, that’s good to know. Are terms like “first mate” and such not used any more?


I think the balloon is called hull. And the cabin is called gondola I think.

Shouldn’t the ranks be named like in airplanes/air force?


In this setting, airplanes were never invented and airships developed out of the tradition of naval ships, so the ranks are more naval-inspired. (Basically because I want a steampunk-esque airship as the setting for the murder mystery; airplanes tend to be too small to have the exploration aspects where the parser format really shines.)


There are some good cross sectional images of zeppelins which might be interesting, though they don’t really include all the internal hidden passages. One interesting thing is that the propellers were suspended outside the ship with an engineer in them keeping it running.


First mate is still a senior leadership (licensed) officer and can also be considered second in command depending on the ship’s command structure.


If you’re okay with semi-plausible fictional technology, may I suggest transitional vaccum ships?

The ship’s bladders start with lighter than air gas, at pressures and temperatures equal to the ambient air at sea level, but (ETA:) [the bladders together with rest of the ship] aren’t buoyant at sea level.

To get more buoyant, the gas is heated to make it expand and lower its density. As expected, as the gas is heated, it (ETA:) [tries to] expand, but the volume of the bladder tanks stay constant, (ETA:) [due to a rigid shell]. Rather than exploding, some of the expanding gas escapes through one way valves, which prevent the escaped gas from returning (ETA:) [to the bladders]. This gas is then pumped through a network of external pipes and radiator fins that work to rapidly cool and condense this gas. This condensed lifting gas is then supercooled and further condensed into liquid holding tanks.

At the same time, this bladder heating process continues, increasing the kinetic energy of each remaining gas particle that strikes the bladder’s internal walls, helping to balance the fact that there are fewer and fewer particles left to make collisions, maintaining the air pressure balance with the air outside of the bladder. Eventually, the air remaining in the bladder is heated until it turns into a plasma, which makes it far far less dense (Like less than a tenth of a percent of the density of sea level air pressure), and thus more bouyant (ETA:) [than the same volume of lifting gas at Standard Temperature and Pressure].

This increased buoyancy helps lift the craft, which increases its altitude. This increased altitude starts lowering the ambient air density and pressure significantly (ETA:) [as air density falls with increased altitude], allowing a key changeover point where the outside air pressure trying to crush the (ETA:) [partial vacuum inside the] bladder has dropped enough that the heating of the bladder can start to back off. With increased elevation, the internal pressure no longer needs to be so high to combat external air pressure.

At a certain elevation, the ouside air density drops to the point that bouyancy levels out, while the reduced difference of pressures inside and out of the bladder allow the container to structurally withstand the outside pressure on its own. This allows the heating to completely stop, and the temperature of the gas inside the bladder cools until it matches the ambient temperature of the surrounding air.

This would be considered an optimal cruising altitude, as no energy would be needed to maintain bouyancy or structural integrity of the bladders. Optionally, specialized vacuum pumps could be used to increase the vacuum in the bladders while reinstating heating as needed to balance the relative increase of outside pressure, but altitude gains after hitting this optimal cruising altitude would need more and more energy with diminishing returns.

To lower their altitude, liquified lifting gas would be released into the radiator pipes and fins a little at a time, allowing it to expand back into a gas, and then released into the near vacuum of the bladders a little at a time, which decreases bouancy and altitude. As the altitude decreases, outside air pressure increases, requiring occasional pauses to accordingly heat the gas in the bladder while closing the one way escape valves.

It’d be a dance between relative pressures, bouyancy, and how quickly altitude was lost. It’d take a skilled crew to handle.

This solves the issue commonly brought up for (ETA:) [pure] vacuum ships needing a super light, yet super stong shell (like diamond) to withstand outside air pressure, as (ETA:) [with this version] both the vacuum and the internal temperature is variable to balance out external air pressure.

Your fictional world would need a good efficient heat source. Magic would work, as would a compact fission reactor. (<— Why no one has tried this IRL. The only thing with less public enthusiasm than a Hindenburg II, is a nuclear Hindenburg II). Author’s choice.

Anyway, the point of all this is a near vaccuum lifting gas allows higher bouyancies than is typically possible (ETA:) [than with the same volume of lifting gas in a classical zeppelin], allowing for relatively smaller bladders and larger cabins and lifting capacities.

ETA: Fwiw, this topic strays into some of my graduate research, so I had a vested interest in this, including a whole line of inquiry in trying to get ammonia to work as a cheaper alternative lifting gas. So, if you wanna talk shop at some point, let me know.

ETA x2: Also would like to point out you wouldn’t need a classical lifting gas like Helium or Hydrogen for this to work. As it relies on superheating to create a low density plasma, something relatively plentiful and benign like nitrogen could be used.


That is incredibly fascinating. I’m going to need to read up more on this!


My first impression still holds, that this is too many rooms to make for good gameplay, unless you’re going for an intensely detailed simulation of life on a zeppelin, or plan intricate timing-based puzzles around navigating through the craft ala Varicella (or this is going to be a long, Infocom-length style game). Most of these areas could be abstracted away via arriving-in/departing-from descriptive text. That way you can focus on representing only a few of the most vital areas in the world model, the places where the NPCs typically are (or that otherwise offer the most opportunities for interaction).


More the former than the latter. It’s not Infocom-length, but the core of the gameplay is that you can’t communicate directly with anyone (due to a language barrier), so investigating the mystery requires a lot of subterfuge: “if I mess with this valve, then the engineer will come fix it; can I block other routes to make sure he comes through this room, so that he’ll unlock the door and I can search it for evidence?”

I may end up cutting the map down, but at the moment it mostly exists like this for the purpose of routing puzzles (messing with other people’s routes to make sure they use the doors you need them to use).


I dunno, I rather like the number of rooms here! But I suppose I’m also a fan of larger maps, and travel timing puzzles, so…


Is it realistic for a navigator (who would need a lot of training to become one) to also be a medic (who would need a lot of training to become one)? I would intuitively have expected a person to be either a navigator or a medic.


I would imagine someone who previously served as a medic could be forced into both roles with a skeleton crew.


Just chiming in to mention that Dr. Piergiorgio (@Piergiorgio_d_errico) is a naval historian (probably the one you had in mind!) and he might be interested in giving his two cents on ship-ly insight.


This would make more sense, but—

This is what I was going for. They were hoping to bring on more crew but had to launch unexpectedly, so their medic is filling in as navigator as best he can.

Indeed! He and @DeusIrae are the ones I was thinking of for particular shiply matters. My experience with ships mostly comes down to playing Return of the Obra Dinn (which involves investigating an East Indiaman) and some less-than-rigorous D&D adventures.

Which is better than nothing—it means I now have an intuition as to how decks might be laid out—but is also a far cry from actually studying this, either practically or theoretically.


I am reminded of another alternate history story about zeppelins: Catch That Zeppelin by Fritz Leiber.


I should also specify: gameplay-wise, the skeleton crew is meant to explain why everyone is up and doing things, instead of half of them being asleep and inaccessible to the player. They’ve normally been sleeping in shifts, but the recent murder has left them both very shaken and even more short-staffed—nobody wants to sleep when they know there’s a murderer on board, and with such a small crew every hand helps. So they’re all awake for the last few hours before landing (when the game takes place).