Deception in space without stealth

[Adam Reynolds]

What would be the best approach for trying to hide what your spacecraft are doing if you can't hide your emissions? The problem of stealth in space is somewhat obvious, as indicated by Atomic Rockets. While there are a few arguments against the assumption based on lack of sensor coverage, I was thinking it might be interesting to work with the case in which you truly can't hide your emissions well enough. What deception options still work?

Obviously this also depends upon what type of science fiction engines are in use, but with any kind of reaction engines, you can probably be detected. If you go with something essentially modern and realistic, fuel limitations dominate and so Newtonian paths are what is most important, as you don't need to fully track ships if you can know where they will always be. On the opposite end of the spectrum, in a setting more like The Expanse with impossibly powerful engines that can ignore gravity, you can't hide because your exhaust plumes are so easily visible that sensors don't have to be all that sensitive(which means that if you don't use full sized Epstein drives, you probably can hide from most sensors).

The most obvious approach seems to be the Q-ship, in which you appear to be some kind of civilian vessel with all of your systems disguised as cargo. The problem with this idea is that it only works as a way in, if it even works in that context. It also requires that there is enough civilian traffic that you can blend in.

Another potentially interesting approach is to use something akin to stealth by impossibility, in which you take a course that cannot be easily followed without a massive expenditure of fuel, because the velocity vectors of patrol craft are all pointing in the wrong direction at the time you thrust. Combining this with the above, if your "cargo" is simply fuel, you might be able to escape before anyone notices you have done so.

Ships are helped during both infiltration and escape by the fact that a lack of stealth means that you would also know the routes of patrol craft as you are attempting to escape, unless those craft also used the same deceptive approach that you did, making their patrol craft appear to be civilian ones until they suddenly turn on their real engines and begin pursuit.

This would also obviously imply a Cold War or modern sort of conflict in which there is almost no direct fighting between peer enemies that can actually throw around patrol vessels and maintain sensor coverage. It would more be about Coast Guard sorts of vessels against armed smugglers, as opposed to full size warships in which you can simply vaporize anyone who looks a bit suspicious. Which is also a somewhat interesting concept, that of a space setting without wars, in which espionage and diplomacy dominate instead of full scale combat.

Is there anything important I'm not thinking of?

[bilateralrope]

The most obvious approach seems to be the Q-ship, in which you appear to be some kind of civilian vessel with all of your systems disguised as cargo. The problem with this idea is that it only works as a way in, if it even works in that context. It also requires that there is enough civilian traffic that you can blend in.

With the added complication that you have to match the mass of whatever civilian ship you're pretending to be. If you get the mass wrong, anyone looking at you will see that your engine flare is the wrong color for the acceleration you're doing.

Another potentially interesting approach is to use something akin to stealth by impossibility, in which you take a course that cannot be easily followed without a massive expenditure of fuel, because the velocity vectors of patrol craft are all pointing in the wrong direction at the time you thrust. Combining this with the above, if your "cargo" is simply fuel, you might be able to escape before anyone notices you have done so.

That won't help you sneak around. Anyone interested in you will just keep a telescope pointed at you.

As for escaping, if your sustained acceleration is better than that of anyone chasing you, your course just needs to be away from any enemies. If your pursuers have better sustained acceleration, you're in trouble regardless of your course.

[The Romulan Republic]

The obvious answer is to disguise warships as civilian vessels, yes. Ie, Q ships. That would entail some compromises in terms of the warships' capabilities, most likely, but could be made up for by the ability to get in a good sucker punch against an unsuspecting opponent.

But bottom line: just because you can see that there's a ship's drive in the area doesn't mean you will be able to tell everything about the nature of that ship and its capabilities until it gets much, much closer.

[bilateralrope]

How well would a Q ship work in a setting where everyone submits a flightplan ?

Any ship flying without a flightplan is suspicious.

Sure, you could try to submit a flightplan saying your Q ship belongs to {transport company}. But that has two problems:
- You risk someone from {transport company} leaking that your ship was never loaded with the cargo the manifest claims.
- {transport company} is probably not going to like you putting a Q ship under their name, as the response to a successful attack is bad for their business.

[Bedlam]

How well would a Q ship work in a setting where everyone submits a flightplan ?

Any ship flying without a flightplan is suspicious.

Sure, you could try to submit a flightplan saying your Q ship belongs to {transport company}. But that has two problems:
- You risk someone from {transport company} leaking that your ship was never loaded with the cargo the manifest claims.
- {transport company} is probably not going to like you putting a Q ship under their name, as the response to a successful attack is bad for their business.

Depends who 'you' are. If you are the transport company then you can have a certain proportion of your fleet as Q ships and just log them the same as anyone else. Maybe your reputation takes a hit but it depends how many other shipping options there are. If you're a government equivalent than you can force companies to support your ships whether they want to or not or if you can hack the flight plan system you can just insert your ship without the transport companies permission.

[Adam Reynolds]

The obvious answer is to disguise warships as civilian vessels, yes. Ie, Q ships. That would entail some compromises in terms of the warships' capabilities, most likely, but could be made up for by the ability to get in a good sucker punch against an unsuspecting opponent.

This is probably not actually something that would be worth it as a dedicated warship substitute. In that case a better solution would be akin to the equivalent of anti-ship missiles carried in shipping containers, though this would also have the same flaw as that proposal in the real world, that it is a war crime. A better solution might just be launching the missiles directly with either a missile bus or simple booster rockets, depending on the types of engines in use. I'm thinking of this more as a substitute for submarines in terms of covert action and intelligence gathering, not direct combat.

The most obvious approach seems to be the Q-ship, in which you appear to be some kind of civilian vessel with all of your systems disguised as cargo. The problem with this idea is that it only works as a way in, if it even works in that context. It also requires that there is enough civilian traffic that you can blend in.

With the added complication that you have to match the mass of whatever civilian ship you're pretending to be. If you get the mass wrong, anyone looking at you will see that your engine flare is the wrong color for the acceleration you're doing.

One way that might work is by having rocket boosters or just extra fuel as "cargo," allowing you to also make your rapid escape. At least as long as no one tries to board your ship for a safety or law enforcement inspection.

That won't help you sneak around. Anyone interested in you will just keep a telescope pointed at you.

As for escaping, if your sustained acceleration is better than that of anyone chasing you, your course just needs to be away from any enemies. If your pursuers have better sustained acceleration, you're in trouble regardless of your course.

Total delta-v would also play a role assuming that is a limit. I don't mean as a means to sneak around, I mean as a means to escape outright after you have been caught. It would also require that there is somewhere safe you can go in the first place that your pursuers cannot follow, like someone escaping from Earth to Mars or visa versa.

The obvious downside is if they're willing to shoot at you, missiles can pull far more Gs than crewed vessels, and lasers would be rather hard to evade regardless of what you try. Though could a laser actually damage a high energy engine? I suppose it might cause overheating and an explosive failure.

How well would a Q ship work in a setting where everyone submits a flightplan ?

Any ship flying without a flightplan is suspicious.

Sure, you could try to submit a flightplan saying your Q ship belongs to {transport company}. But that has two problems:
- You risk someone from {transport company} leaking that your ship was never loaded with the cargo the manifest claims.
- {transport company} is probably not going to like you putting a Q ship under their name, as the response to a successful attack is bad for their business.

I hadn't thought of that one for some reason. This is also a problem for spies and other covert actors who want to go somewhere in person at the individual level even today, and with a speed of light lag and presumably bandwidth limits to the internet between Earth and Mars, you would have more of a need to go somewhere in person. So it's a problem that you would need to find solutions to in more ways than one. It certainly would be expensive, which would mean that it could only be done when it was truly necessary. One approach might be to actually create independent trading companies owned by intelligence agencies for this purpose, something the CIA has actually done. On the individual level, officers have had their identities entirely thrown away for a single operation.

Currently one of the solutions is the use of corporate spies on behalf of nation states. As long as they aren't being used as true warships, it might actually be possible to get a company onboard, as long as something useful can be offered in return. I give you a valid shipping registration, and in return those pesky pirates get taken care of without any questions asked. Both of these approaches are extremely expensive, but then so are submarines. The downside is that these ships and their covers can't be used in wartime without major problems diplomatically, which might or might not be worth it.

[bilateralrope]

Depends who 'you' are. If you are the transport company then you can have a certain proportion of your fleet as Q ships and just log them the same as anyone else. Maybe your reputation takes a hit but it depends how many other shipping options there are. If you're a government equivalent than you can force companies to support your ships whether they want to or not or if you can hack the flight plan system you can just insert your ship without the transport companies permission.

When I'm talking about the transport companies reputation taking a hit, I'm talking about the target government (and probably other governments) going: You lied about what was in that ship, so we are banning you from space/facilities that we control. Maybe we will let you in if you submit your ships to thorough searches.

How willing various governments are to ban a transport company does depend on how many there are. The fewer there are, the more it costs to ban one. But the more power any one company would have to refuse to allow a Q ship, because they can threaten to stop flying ships to the government that wants one.

When it comes to governments forcing a company to fly a Q ship*, the question becomes: Is it better to force an unwilling company to fly a Q ship or use other political pressure on the enemy government through sanctions or other trade restrictions ?

When we are talking about hacking, it's a similar question. Is it more effective to target the enemy governments flight plan system or one of the other systems ?

*Or, more likely, load up a transport ship with soldiers and weaponry instead of building a new ship.

I'm expecting a lot of spycraft, hacking and trade restrictions long before anyone tries any military action.

[Juubi Karakuchi]

If I understand rightly, there are ways of defeating - at least partially - most detection methods. Technology already exists to at least complicate electromagnetic (Radar) detection, while visual detection can at least theoretically be complicated or defeated by purported 'invisibility cloak' technology. A 'cloaking device' that defeats radar and telescopes is thus theoretically plausible.

The one that none of them can defeat - and the one Atomic Rockets keeps harping on about - is thermal detection; for the simple reason that heat has to go somewhere. In the case of the engine flare - as has been mentioned already - it can be detected both visually and thermally. But even if it isn't giving off an engine flare, a ship can be detected by the heat radiating away from it. This can technically be defeated by using thermotic hull plating - or anything that blocks the transfer of heat out through the hull - but this comes with the drawback of the heat building up inside the ship. At the very least, this inflicts a time limit.

That did raise one possibility to me; that of 'thermal dazzling'. The idea came from the dazzle camouflage used on warships in WW1 and WW2. The idea was not to hide the ship, but to confuse observers by breaking up the outline, making a ship seem smaller than it was, or going in another direction, etc. There's some disagreement as to how well it worked - some U-boat captains claimed it fooled them - but it was generally rendered useless by radar.

The idea in this case would be to use thermotic hull plates and radiators to block or release radiation in specific patterns. It might not confuse an observer as to a ship's location or heading, but it might confuse as to its size and configuration.

[Formless]

Actually, Matterbeam has a really good argument for thermal detection being totally defeatable. He calls it the "stealth steamer", and it takes advantage of how the engine nozzle is designed so as to cool the exhaust before expelling it. Basically the nozzle is s shaped and really long. It's not meant to be fast, but the overall design runs cool enough that a detector can't easily distinguish the ship's emissions from noise. That way you can get spy ships and strategic weapons from planet to planet easily, if slowly.

The same trick could be used to Change a ship's engine's thermal profile to look like a different class of ship.

[Solauren]

'Core out' asteroids, and put the ship inside of it. Get it up to speed, and then close the area over the engines. Now it's just a fast moving asteroid.

[Dass.Kapital]

So, just adding an idea.

One idea is to 'Chill' things down as much as one can while safely home in your own sytem with lots of orbital clutter to hide behind/in before using some sort of auxilary system (Discardable) to boost towards target system.

Another idea is finding excess mass and using its internal volume/mass as a 'Heat dump'.

My favourite is an astronomical version of a 'Ghilly' suit. Carry exess hydrogen and oxygen. Useful as re-mass, coolant, life support etc. Have some extra piping around the vessel. Spray ice'water out around th coasting ship and *Puff* now you're a metal rich comet coasting in from the ort cloud.