The flight craft in my Dieselpunk-ish Science Fantasy setting are heavily inspired by the Hovercraft of The Matrix series. I think that those ships have a very interesting look, and they are the first levitating craft that I saw with actual visible engines.

Though unlike the hovercraft from the Matrix which use magnetic-levitation, my craft utilize the Cosmic Aether. However other than that one fantastical quirk the engines utilize similar principles.

My question is from where do I even the ship's excess heat? This is more for my peace of mind, and it isn't likely to be all that important in the story.

I drew inspiration for the managment systems from Mass Effect in particular The Normandy's stealth-systems and a few bits from Atomic Rocket, and one major piece of Unobtainium. Ships circulate coolant, the cycle ends in massive heat wells that are connected to radiators. The Heat wells incorporate a rare and difficult to synthesis mineral(the afore mentioned Unobtainium),this mineral is very heat conductive and has an exotic structure, it partially exists and radiats heat outside three dimensional space. However the mineral doesn't radiate heat at a high enough rate to eliminate the need for external radiators.

So I ask where exactly do I put them on my ships?

  • 2
    $\begingroup$ I recommend calling your ships something humans could pronounce. $\endgroup$ Jan 20, 2016 at 19:00
  • $\begingroup$ @XandarTheZenon Compared to some words I've seen, "aether-pteron" is really easy: eTHUR TERRon. $\endgroup$
    – Frostfyre
    Jan 20, 2016 at 19:03
  • $\begingroup$ Oh, I was trying to pronounce the p. Probably clear that up somehow in your story. After all, you pronounce the p in ornithopter, and you said it was a nod to those. $\endgroup$ Jan 20, 2016 at 19:06
  • 1
    $\begingroup$ @XandarTheZenon Tangential Fun Fact: "Worcestershire" was voted the hardest word in the English language to pronounce. $\endgroup$
    – Frostfyre
    Jan 20, 2016 at 19:08
  • $\begingroup$ I wholeheartedly disagree. That is easy to say in every way. Today. Hooray. Thanks for he tidbit, though. $\endgroup$ Jan 20, 2016 at 19:11

3 Answers 3


The weak spot

These external radiators would be a weak spot for your construction. Heavy armor just doesn't radiate heat well. While the ship is pulling off normal maneuvers, the unobtainum removes the heat just fine and these extra radiators are unneeded.

However, if you want to void your warranty, (after all, they only guaranteed it to be bullet-proof for one month anyways) a mod shop can add some radiators. They're typically on the sides of the ship, in a trapped vortex:

Trapped Vortex

These can dump heat into the environment, but the vortex is usually covered by heavy armor, limiting efficiency. You can then overclock your engine to perform awesome maneuvers by removing the armor - through the user-friendly control panel to remove the panels, usually via small chemical explosion, or to open them a crack with small electrical motors. Either one works. However, this is now a weak spot, as the armor has been compromised in this area. Good luck and hopefully the added agility will outweigh any loss in the armor.

  • $\begingroup$ My initial idea for the location of the main vents was the belly and back of the ship; I got away from that Idea when it occurred to me that their is probably a loading.boarding ramp or lift in that area and being near the thermal-exhaust probably isn't all that safe. Why did you suggest that the main vents be on the sides? $\endgroup$ Jan 20, 2016 at 22:30
  • $\begingroup$ They can be hidden there without to much damage - the hardest hitting attacks (in terms of kinetic energy) are from the front, the most common hitting attacks are on the rear (and placement on the rear will seriously reduce convection, the fastest way to remove heat). On the side in a trapped vortex, the weak spot is protected from both of these sources - only a lucky side shot can hit it. But, in this configuration, convection is still active and the system can really dump some heat. $\endgroup$
    – Mark
    Jan 20, 2016 at 23:00
  • 1
    $\begingroup$ First what exactly is a trapped vortex, and how does it relate to heat venting? Putting un or even completely armored main-vents on the side. Makes the broad sides even more of a vulnerable point than I had thought. Borrowing from Mass Effect some ships, mostly the warships to have spinal mounted main guns. $\endgroup$ Jan 21, 2016 at 1:12

If it is a real hovercraft, the heat can be dumped into the plenum and vented with the air being used to provide the air cushion. If this is done properly, the only weak point is actually underneath the craft (which in a hovercraft is one of the weak points anyway, since the plenum needs to be open at the bottom for the air to form the cushion below the vehicle). enter image description here

For coleoptres and ducted fan aircraft, something similar can be done, venting the heat into duct where the constant airflow will pass over the heat exchanger surface and carry the heat away.

enter image description here

How this affects the story is up to you, of course. If the heat exchangers are buried inside the hovercraft or inside the ducts of a ducted fan, there will be complications for inspection and servicing.

  • $\begingroup$ The closet real world technology to hovercraft of my setting would mag-lev,albeit far more advanced than anything currently in existence. $\endgroup$ Jan 21, 2016 at 20:08
  • 1
    $\begingroup$ Terminology is important. A Mag-lev is far different from a hovercraft, so the answer then would be to put heat exchangers where they can have free access to the air stream. You may end up with radiator housings on the outside of the craft similar to the belly scoop of the P-51 Mustang fighter of WWII fame. $\endgroup$
    – Thucydides
    Jan 21, 2016 at 20:34
  • $\begingroup$ The Hovercraft in my setting float and propeller themselves by grabbing onto and pushing against the aether an all pervading field of particles. The closest real world system to how aethereal-engines work, would be magnetic levitation developed to the point where a craft could fly by repelling against earth's magnetic field. Another postes @Mark suggested that the radiators be on the sides of the ship, why do you feel as though they should be on the bottom. $\endgroup$ Jan 23, 2016 at 22:11
  • $\begingroup$ When you said Hovercraft, then putting radiators in the plenum make sense. The belly scoop of a P-51 is an example of what a radiator housing might look, but it can be anywhere there is free access to the air stream; on the sides, on the belly or even on the top. $\endgroup$
    – Thucydides
    Jan 24, 2016 at 0:11

If it isn't likely to impact the story, I would put it in a location that is most advantageous as a plot device at an opportune (or inopportune) time.

  • Perhaps it is on the roof of the vessel, thus when successfully hiding from the enemy above, the heat vent gives them away.

  • Perhaps the back, so at the last second you can pump the heat exhaust for a tiny amount of thrust when really needed.

  • Conversely, on the front (or one/both of the sides), it could be vented as a hot stop maneuver, a la The Martian (or hard turn, if it's on the side).

  • Perhaps it's on the bottom, where the evil stowaway is hiding, and accidentally gets cooked because s/he didn't realize it was a heat vent... or maybe you land on something that's covered with something flammable, that accidentally (or on purpose) ignites when you're landing or taking off.

Of course, when dealing with exhaust vents, beware of magical farm boys using explosives. Just, you know, in general.

  • 1
    $\begingroup$ Psionic farm boys are no threat to the ships systems, since the vents don't lead into into the super-structure. $\endgroup$ Jan 20, 2016 at 22:19

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .