If the ship's self-destruct is such a great idea why don't real Navies do this? [closed]

Question

Background to my question:

I watched a recent episode of The Expanse where the ship's captain

self-nuked a main battleship/flagship to keep it from being captured.

It got me thinking, in-universe this appears to make no sense!

Ships having a self-destruct is a thing across many books/movies. Is this done only for "drama"?

Scuttling a ship and/or melting down certain tech (cryptography machinery e.g.) prior to capture makes good sense regardless of setting but blowing everything and everyone up seems a mere conceit to the writers craft.

I can imagine that at times a self-destruct may fit the story - Borg assimilation or other wars of total annihilation of the human species. Otherwise it just seems dumb to me.

Further proof of this device being merely a conceit, and not a coherent in-universe thing, is the fact that no matter how badly damaged the ship is it always retains the capacity to self-destruct. All other systems are fair game for being knocked off line but the self-destruct is somehow indestructible (until it's actually used of course).

Even the movie Galaxy Quest pokes fun at this by having the characters fail to disable the self-destruct at the last moment and it doesn't blow up because, well, it never has before so obviously it's supposed to be built to stop at 0:01:14 time remaining :D

Am I missing something?

~~~ So here's my edit. ~~~

There is lots of talk in answers and comments about "scuttling" a ship. I'm not asking about how one might scuttle a spaceship. If you re-read my question, now helpfully bolded or italicized to show clear emphasis, you will see I call out scuttling as a sensible procedure.

What is not sensible is atomizing the ship in a massive explosion, particularly while friendly people are still on board or near-by. Self-destruct is not scuttling a ship! It's turning it into a crazy up scaled IED. As it is usually presented, self-destruct is simply insane. And itt's the suicide-bomber part that bothers me.

If it was such a great idea it wouldn't be found only in fantasy literature, right?

As for methods of effectively scuttling a spaceship.

"Scuttle" it into a gravity well; "Scuttle" it by radiation "leak"; "Scuttle" it by fusing all critical electrical components; "Scuttle" it by giving it extreme rotational momentum at the time of abandonment; etc.

Excepting in science-fantasy settings, the hard vacuum of boundless space is a great place to scuttle a ship. Especially if you've toasted the critical components, then salvage is of dubitable worth. And for those who think spinning a multi-thousand-metric-ton ship at high speed and sending it off into deep space isn't a good way to scuttle it, then you need to consider how you would actually go about salvaging such a ship. How apart from tech that is really just a different name for magic that is (cough>transporter< cough).

~~~ So here's my 2nd edit ~~~

It seems the USS Halibut may have been under orders to scuttle itself with all hands on board if necessary to avoid capture. While this is seemingly a real example of mass suicide by the decision of one (or a few) senior officer(s) as a standing order,

it still fails as a direct comparison of what happens in The Expanse. Given the tech level exhibited in the show, self-destruct is a completely unnecessary method of keeping secrets IMO.

https://en.wikipedia.org/wiki/USS_Halibut_(SSGN-587)

Answer 1

There's some things that make a self destruct system make sense in SciFi, but not in real life.

1. Starships are already bombs: Most of the time spaceships use some form of anti-matter, black hole, or highly energetic unobtanium. All of the ship's power engineering systems are designed to continually prevent a catastrophic explosion. A 'self-destruct system' consists of disabling safety systems. These systems generally can't fail, because if the safety systems do fail, they ship blows up right then and there. In the real navy, there is nothing similar. Ships would need to be carrying around extra explosives just to turn themselves into a suicide IED. The space used for those explosives would be far better reserved for non-suicidal weapons.
2. Starships are fast: Most of the time, if you are going to turn your ship into a kamikaze IED, you want to blow just as you are ramming into your opponent. With FTL, impulse, shields, or other SciFi tech, ramming can be possible. In the real Navy? Ramming isn't a thing. It doesn't happen. Since the Age of Sail no ships have been successfully rammed. With the advent of iron ships and cannons on turrets there is simply no way to get close to another ship from typical naval engagement ranges.
3. Unknown possibilities: We are talking about ships that are exploring unknown space. Space that might have technologically advanced hostiles. You might not have the time to send your ship spiralling into a gravity well or any of those other options you listed.

Also, I don't know what aspects of them being a suicide bomber is troubling you. If you want to say what exactly is troubling I'll edit this and address it. That being said, from the Kamikazes in WW2 to Muslim Extremists today, when suicide bombing is the tactically superior choice, it will be used. When your ship is being shot out from under you and your tactical options are:

1. Die with all hands aboard
2. Suicide bomb, take out the bad guy; still die with all hands aboard

Well, suicide bombing IS the tactically superior option there.

Answer 2

On the One Hand: Often self-destruct is not a feature of the ship, but is more of an option inherent in the power / propulsion system. If you turn off all the safeties and let the warp core / nuclear reactor / unobtainium go out of control, it will overload and blow up the ship.

You could, in theory, allow a reactor meltdown to happen on a nuclear powered ship and it would melt the reactor chamber and kill everyone on board due to radiation exposure. It may melt its way outside and sink the ship as well.

Such as K-431 which had an unintentional accident during refueling which resulted in an explosion.

At 10:55 AM the starboard reactor became prompt critical, resulting in a criticality excursion of about 5×10¹⁸ fissions and a thermal/steam explosion. The explosion expelled the new load of fuel, destroyed the machine enclosures, ruptured the submarine's pressure hull and aft bulkhead, and partially destroyed the fuelling shack, with the shack's roof falling 70 metres away in the water.

You could also kamikaze your ship into another. This will likely result in it being ruined and be detrimental to the crew's health.

On the Other Hand: I think most crew would be very demoralized working on a ship that could at any moment self-destruct. That is why in real life usually a little work is required to destroy an asset, instead of having a button ready to kill the ship should you accidentally lean too hard against it.

And on the Gripping Hand: Traditionally navies have used scuttling to cost effectively destroy assets they don't want falling into enemy hands. Warships could also purposefully detonate ordinance that is on the vessel (be it torpedoes, gun powder, or rockets).

Scuttle:

to sink (a vessel) deliberately by opening seacocks or making openings in the bottom.

Answer 3

Historically, scuttling ships has been fairly common. Warships are expensive and valuable assets, if you have one of your ships destroyed then you have just lost one, if it is captured not only do you lose it but your enemy has gained use of it so you are now effectively two ships down.

In 1942 the French Navy scuttled most of their fleet at Toulon to prevent capture by German Forces. Another well known example from WWII is the Graff Spee, scuttled at Montevideo after being trapped in port by a British fleet.

As well as denying the ships themselves to the enemy scuttling could be used to protect secret information or technology eg in the case of U-110 where this was unsuccessful.

Ships may also be scuttled in shallow waters or deliberately run aground for tactical or engineering reasons for example to deny access to a harbour or to quickly create a breakwater.

In practice ships tend not to need a specific 'self destruct' system as they can either use their own munitions to breach the hull or allow the hull to flood, for example a submarine could be quickly flooded by opening both the inner an outer doors of its torpedo tubes.

Clearly there isn't a direct equivalent of 'sinking' a spacecraft so it seems reasonable that they would require something a bit more active to put it beyond use, what this might be would depend on the technology involved.

To answer the question why warships don't self destruct the answer is that sometimes they do (eg the Graff Spee again). This usually occurs in circumstances where the crew have plenty of time to prepare the explosives required and to escape safely and when this would be more effective than simply sinking the ship eg in shallow water.

The 'suicide bomb' aspect of the question depends on whether the crew have any means of escape and some form of escape pods or shuttle craft are common enough in sci-fi. Similarly a space craft offers many situations where the crew are either already dead or have little chance of surviving eg due to hull depressurisation or radiation exposure. Equally any self destruct with a timer implies that the time is for the crew to escape, otherwise what is the point of having a countdown. In any case any measure which puts a ship beyond salvage is going to stand a fair chance of killing any crew left on board.

It may also be that the only way to prevent the ship being captured is to improvise a way to destroy it eg by detonating its munitions on-board, in which case it is not a planned feature but a desperate decision.

Answer 4

Why don't real navies use dedicated mechanisms to allow for quick self destruction when the need arises?

Every naval force still trains its men to scuttle ships, and has in-depth protocols for such a situation, but they don't have a "self destruct" system ready to go at the push of the button for a number of reasons:

• Because scuttling a ship is a last resort to keep the ship and/or its cargo from falling into enemy hands, and it doesn't happen very often.

• Because our technology is limited. The only means I can imagine by which a ship could be scuttled are:

  • Rig the bilge pumps, hatches, etc, to allow water in, or actively suck water in.

  • Rig the hull with explosive charges, and don't arm them until they are needed.

    Both of these options are problematic: Both might fail when you need them, after sitting idle for most of the ship's life. Both might trigger when they shouldn't, either through accidental malfunction or malfeasance/sabotage, leading to the loss of the ship and/or some or all of the crew for no reason. And the explosives, even if they aren't armed, might detonate (partially or fully) if the ship is attacked, or even if it hits a patch of rough seas and gets banged around a bit.

• Individual ships, in and of themselves, aren't that important anymore, and in the unlikely event that, say, a USN vessel was captured intact, it wouldn't be that big a problem:

  • The real danger in capture would be the intelligence (data), intelligence gathering devices, and weapons systems on the ship. The crew would almost certainly be trained to render these useless to the enemy before capture. The computers, etc, could be disabled rather quickly, probably according to predetermined protocols which the crew had been trained in beforehand.

  • The ship's crew would alert command on other ships and on the mainland of the situation, and it would be relatively easy for command to order a strike on the ship after it was captured - either by launching a remote attack via bombers and missiles, or by ordering a special forces assault (probably by Navy Seals, in the USN) to retake the ship.

• The smaller the ship, the easier it would be for the enemy to capture - it is hard to imagine a force large enough to successfully overwhelm an aircraft carrier, with hundreds of aircraft, and thousands of crew. And the smaller the ship, the less useful it would be to the enemy, and the less threat would be posed by its capture.

  • For example: It would be relatively easy to overtake a Navy tug, but why would you bother? If you can afford such an operation, you can probably afford to buy a tug yourself. And even if it was cheaper to steal a tug than buy one, it would make more sense to steal a civilian tug - civilians can't call up the Navy to get their tug back; the Navy can.

    In other words, if you have to steal a tug, and you have a choice between stealing it from people who have Navy Seals (or their international equivalents) at their disposal, or people who don't, why would you choose to steal it from the guys who can send in the Seals?

    More generally, you can steal a small ship easily, so why steal one from any navy, knowing that it will either lead to serious legal problems (far more serious than just stealing a civilian ship), possibly trigger an international incident, and almost certainly lead to lots of trained military personnel with very big guns trying to murder you?

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My buddy who is an officer in the US Coast Guard confirms this:

I can tell you that scuttling plans were still a real thing as of when I left my underway assignment in 2002. We had shallow water and deep water scuttling instructions, and friendly/hostile seas instructions. As the Damage Control Assistant, my job involved running down ladders with a large sledge hammer. My engine room duties involved disabling the heavy machinery in ways that if the ship were recovered by enemies it would be worthless mechanically. The combat officer took steps to prevent sensitive information and systems from falling Into enemy hands - not sure how specific I should get, can't remember how much of a trade secret this was.

As to why we don't have a dedicated system or a button - the basic answer is one of the ones posited [in this answer] - a combination of maintenance and the fact that even if you had explosives without a charge set, if an enemy could learn where those explosives were then sinking a ship and killing many of the sailors on it becomes a LOT easier. Even the important stuff isn't set to fry on its own - it needs some combination of matches, axes, or magnets operated by people to fry it.

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In short, scuttling is rarely necessary today, so it isn't worth the risks involved with rigging your ship ahead of time to sink at a moment's notice on the off chance that you'll need to do it. If you try to scuttle your ship when the need arises, you might be overtaken before you can do so, but even so, it isn't as big a problem as it might have been in the past. This doesn't change the fact that sailors are trained in scuttling; however, it is rarely done.

Answer 5

Credit to @CBredlow (I had no idea): "They do implement a self-destruct on real spacecraft. If a launch is off of intended trajectory and is a potential danger they will order the rocket to self destruct."

(source)

Navies can scuttle any seafaring vessel with the help of Poseidon alone. Astronauts need something with a little more kick. It is therefore decidedly not only found in fantasy literature. On the most efficient space-faring warships the option to deploy "Wal-Mart rubber boats" just wouldn't be there.

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Because in space you get to drive angry: Mutually Assured Destruction. If Earth ever went MAD we wouldn't be having this discussion.

This is the best tactical decision available to the captain of the ship. Not only can she not risk her ship being captured, she must insure the safe escape of those who can prevent an all out war and also the data to that affect. She knows she's outgunned so she has to press the button.

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It's turning it into a crazy up scaled IED. As it is usually presented, self-destruct is simply insane. And it's the suicide-bomber part that bothers me.

Unfortunately, there was a navy that utilized that tactic successfully at least 730 times.

Kamikaze aircraft were essentially pilot-guided explosive missiles, purpose-built or converted from conventional aircraft. Pilots would attempt to crash their aircraft into enemy ships in what was called a "body attack" (体当たり; 体当り, taiatari) in planes laden with some combination of explosives, bombs, torpedoes and full fuel tanks; accuracy was much better than a conventional attack, the payload and explosion larger. A kamikaze could sustain damage which would disable a conventional attacker and still achieve its objective. The goal of crippling or destroying large numbers of Allied ships, particularly aircraft carriers, was considered by the Empire of Japan to be a just reason for sacrificing pilots and aircraft. –Wiki

Yes, it's insane and it bothers me too. Watching videos of them makes me want to throw up.

Answer 6

The other answers go into great detail of how scuttling is the modern day self-destruct. As for why on science fiction the have an actual self destruct sequence as opposed to the manual scuttling procedure, it is because they have a viable option that can actually be automated.

Generally in sci-fi the ship's propulsion system makes use of a fuel/energy source that can be highly unstable and is very energetic. I.e, it is a bomb just waiting to go off. The warp core breeches in Star Trek bring a prime example. In this case you just need the self-destruct algorithms to disable the safeties and set the system to go critical and boom. We don't have anything comparable in the modern Navy, hence the manual scuttling procedures.

One would imagine that those future crews also drill on how to manually self-destruct their ships. The primary manual process would probably still be to make the reactor go critical. Secondary methods would exist for when the reactor is offline or maybe previously ejected because invests going critical. Generally, of course, the majority of the crew would evacuate before using the automated or manual methods.

Answer 7

Scuttling starships in a method similar to ships at sea is impossible because there's no guarantee of a nearby ocean to take advantage of. Systematically destroying sensitive material is also rather slow. A lot of the methods the questioner suggested involves the ship having full engine power - in which case, why scuttle at all? Why not just attempt to escape?

The best comparison is not actually ships at all, but instead, tanks.

WWI tank example https://www.awm.gov.au/collection/E04927/

Or this Panther https://i.sstatic.net/G7ARb.jpg

For tanks, the traditional way to destroy them is by internal explosion, using the tank's own remaining ammunition reserves, or a dedicated scuttling charge.

Answer 8

I wanted to address one comment in particular from the question.

"Scuttle" it into a gravity well;

In-universe for The Expanse, there is no FTL travel. More to the point, there is little travel at much more than 1G, except in emergency. This means that you could be days or weeks from the nearest gravity well, assuming your ship is capable of travel at all. (i.e. not incapacitated)

There is also the small matter of what's at the bottom of the well. There are several passages in book 1 in particular where they mention space warfare with rocks. I.e. all that the attackers have to do is start dropping rocks (asteroids) down the well; meanwhile, the defenders must specifically target the (much smaller) ships of the attackers. Damage to the defenders' infrastructure and population would be catastrophic, but the attackers would be relatively unscathed.

So even if you're near a gravity well, it might not be one you want to drop your ship down.

Answer 9

Scuttling is useful, but self-destruct is more of a plot device than anything else.

The goal of destroying valuable information and material before it falls into enemy hands is a very logical scorched earth policy. We see it in militaries all the time. However, it is typically well controlled. The logic is simple. On a normal ship, the vast majority of the ship is not all that sensitive. We don't mind it if the enemy gets their hands on a lot of things. However, there are a few things that are highly sensitive. These are things which, if falling into the hands of the enemy, are unpredictably dangerous. Obviously "a working warship" is something which would have unpredictable costs if the ship was taken over, so crew will go to make sure bringing the ship back into service is a maintenance nightmare. We see a similar policy for military arms which need to be removed from service. They are often rendered unable to fire by welding pieces of metal in places which are very difficult to repair without doing damage to the essential structure of the gun. This is far easier than outright destroying the gun.

The other thing which needs to be protected are secrets. In warfare, knowledge can be well over half the battle. These need to be destroyed to prevent them from falling into enemy hands. Such knowledge items as papers, codes, and sensitive hardware are easy to reproduce back home, but dangerous in the hands of the enemy. People will be told to destroy them.

So why the self destruct? There's a few reasons I think it is popular, all of which stem from the lack of audience understanding of the ship. In a real ship, people have literally spent their careers learning the ins and outs of the ship. All of the little details are in their heads. If they need to destroy it they can be efficient, targeting the weakest parts of the ship. In a show, its hard to convince viewers that just crumpling this one tube over here and filling the gas tank with sugar is going to cause some enemy mechanic to shake their head and say, "This isn't worth repairing." Better to make sure the viewer knows the hardware's going nowhere. Likewise, the viewers are typically not aware of what secrets are most important, and where they are kept, especially since the writers may not know either!

Finally, consider the suddenness. Captains in storylines are often asked to scuttle their ship on a moment's notice. There's a few issues here. First is that a real captain's job is to not get that surprised. The second issue is that real ships get thousands of man-hours dedicated to exploring these what-if situations, and try to make it as reasonable as possible to manage the destruction of what matters. The staff of a writing team and special effects teams may have a total of thousands of man-hours to build the entire ship, if they're lucky. Thus, a realistic captain trying to scuttle the ship in a realistic way would quickly reveal all of the shortcuts the team had to take in using a budget of a few million to write a story about a ship whose budget was in the high billions.

Answer 10

The equivalent of self-descructing a spaceship is scuttling a (sea)ship. Real navies do have that. In fact, all ships can be scuttled.

All ships have a feature called a sea chest, which is a recess in the hull from which water can be drawn for e.g., ballasting and fire-fighting. Water is pumped into the interior of the ship for whatever purposes through pipes, which are, as I recall, typically somewhere in the region of 15-30cm in diameter. To allow these pumps and pipes to be replaced when necessary, there is a valve at the start of the pipe: you close the valve, replace the pipe, then open the valve again. To scuttle the ship, you close the valve, remove the pipe and open the valve: you now have a fairly large diameter connection between the sea and the interior of the ship, and seawater gushes in at a rate of up to tons per second. Ships are sometimes lost because repairs to the sea chest inlet pipes go wrong (e.g., Sea Breeze off south-west England in March 2014.

Perhaps a closer analogy would be aircraft. Some military aircraft, such as the Lockheed U-2 do have a self-destruct mechanism which destroys parts of the plane with explosives to avoid them falling into enemy hands. Likewise, the when a U.S. EP-3 aircraft collided with a Chinese fighter plane sustaining damage that forced it to land, the plane's crew destroyed much of the equipment on board (by pouring coffee into the electronics!) and dumped more into the sea. That probably didn't involve explosives but the crew of the downed helicopter in the Osama Bin Laden raid did use explosives to destroy sensitive parts of that craft after it crash-landed.

Answer 11

The benefits to a self destruct mechanism is:

• explosions tend to be pretty irreversible for everything you want to destroy
• you take out any enemy bad guys that happen to be close enough
• explosions are easy to create, especially on war ships with lots of explosive armaments
• explosions are quick. Once activated, you don't need to do any additional work to finish them.
• explosions are not partial. An explosion will never be interrupted so that only part of the ship is "blowed up".

The down side to alternatives:

• gravity well may not be close, or may be a friendly planet, so it wouldn't always be an available option. Also, you would need to drive into it - attacks may foil you by taking out your propulsion early, thus removing this option.
• radiation leak may render much of the hardware unsafe for people to be around, but what if they send in a robot to look through computer files and salvage any tech? They may be able to reverse engineer it based on a robots detailed analysis, pictures, and video feeds. Or even through remote operation of the robot.
• extreme rotation seems interesting, but not necessarily irreversible. Perhaps throwing a bunch of sticky foam at it until it slows down? If the rotation is so extreme that nothing sticks, the ship will probably fly apart, and how is that different from an explosion? Also, it takes time to ramp up, during which an attacking force could take out the propulsion units providing the rotation. If you have unlimited time to plan your scuttling, then sure. But if you need to make a quick decision, then this might not be an option.
• fusing electrical components is fine too, but there are lots of electrical components on a ship. Would you take the time to fuse them all? You'd have to install fusing mechanisms in every hard-drive and media device. What if the the tech you are trying to protect is on a USB stick transported by a VIP? Or it is some documentation? You are not always just trying to protect your ship from falling into the wrong hands. Maybe there is something else on the ship you are trying to protect.

So in my opinion, there are many valid reasons why a self destruct explosion would be a good idea.

In the Expanse, the Mars ship invoked the self-destruct only when the enemy combatants threatened to breach their bridge. If they had succeeded, they might have obtained codes which would put the entire Mars communication systems at risk. Maybe they could have destroyed the codes, but perhaps the captain and officers could be captured and coerced (tortured) to reveal secret information. The self destruct mechanism was suicide, but the officers and captain agreed it was for the best interest. Also, it was a mutual destruction - none of the enemy survived.

In this case, there was a battle and the Mars ship was about to lose. The Martians were being killed and there seemed to be the thought that the attackers would not stop until all were dead. The self destruct transformed the result from a complete defeat to a stalemate. In fact, it was a minor victory if you consider that it enabled Holden and crew to escape.

To me, the plot hole is that the attackers did not anticipate the self destruct, or knew about it and tried regardless. A more intelligent attacking force would have retreated with a few of their ships to a safe distance while their boarding units attempted to secure the ship. That way, at least some of them could survive if they were unable to secure the bridge before the self destruct was activated.

In the books, there is a bit more detail to this. There are three main stations on the ship: engineering, the bridge, and one other (I can't recall). Two of these are required to invoke the self destruct, so if one of the three is breached, the other two will destroy the ship before any sensitive data can be collected. Holden likens it to a race where the attacking force tries to secure two of the three before the defending force realizes hope is lost and destroys the ship.

Answer 12

There is a false dilemma here. Your assumption is:

• Self destructs are common in scifi
• Self destructs are not common in RL
• Therefore, it probably doesn't make sense

It is important to consider how in many scifi universes, the time a crew might have to scuttle/incapacitate is on the order of seconds. A crew can be killed or removed much more easily in scifi universes than a real-life world crew removed from a ship. This makes it more important for them to have an option to "scuttle" their ship quickly, reliably, and easily.

Second, in those universes, it is possible and probably that a self-destruct is far more reliable and safe than it would be now. They are all done differently, but it might be completely safe in the their world -- but it would not be safe given 2016 technology.

The purpose of scuttling is to prevent someone else using the ship or getting access to information about how it works, important sensitive information, etc. This works well in oceans where you can put it several thousand feet (or even several miles) below the surface. Or when your crew has time to make an orderly destroy-everything-and-sink-the-ship process.

If it was possible for an aircraft carrier in World War Two to have their crew immediately and entirely removed within a few seconds, I imagine that both the United States and Japan would have considered more "quickly self destruct" types of features on their ships.

Keep in mind:

• In future technologies, a self-destruct can be more reliable and effective than it could be now
• Pondering why future tactics aren't currently used when the fundamental technology is different is not a valid comparison in any sense
  • It's like saying in 1720, "people in the future [2016] use missiles and machine guns, but people in 1700s don't - it must not be a valid tactic to use. If it's a great idea why does no one do it?"

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With space and your specifics:

"Scuttle" it into a gravity well

What if you aren't by a gravity well?

"Scuttle" it by radiation "leak"

This is as nice idea in theory, but nearly all scifi series/shows involve some sort of "radiation suit" which makes it invalidated.

"Scuttle" it by fusing all critical electrical components;

Removing the critical components doesn't mean you are blocking the ship from being useful.

"Scuttle" it by giving it extreme rotational momentum at the time of abandonment; etc.

Many scifi shows have some sort of tractor beams. This might be difficult to intercept in real life, but in scifi it normally isn't. Consider that in Star Trek ships intercept each other and close ranges at warp speed.

Excepting in science-fantasy settings, the hard vacuum of boundless space is a great place to scuttle a ship. Especially if you've toasted the critical components, then salvage is of dubitable worth. And for those who think spinning a multi-thousand-metric-ton ship at high speed and sending it off into deep space isn't a good way to scuttle it, then you need to consider how you would actually go about salvaging such a ship. How apart from tech that is really just a different name for magic that is (cough>transporter< cough).

It's a good place to scuttle a ship using current, real life technology limitations.

Answer 13

1. Space is big, harbours are small.

When scuttling in real life one often gains two advantages; keeping the ship from falling into the hands of the enemy, and blocking sea lanes that are of more use to the enemy. Scuttling has in fact been done with blocking a sea lane as the primary objective (e.g. the Skuldelev ships sunk by Vikings around 1070 and now on exhibition in Roskilde were sacrificed to make a waterway impassible).

This wouldn't impact on space battle in the same way, at least not with the sort of manoeuvrability most other spaceships would have in such stories. Hence there's no advantage to leaving a salvageable, but inconvenient, wreck.

2. Space is big, inhabitable areas of the Earth are (relatively) small.

Navies would not generally scuttle a nuclear-reactor powered ships by deliberately causing their reactors to blow near an inhabited area. Even doing that in enemy territory could be considered illegal. Blowing up a spaceship far away from anyone (or anyone who isn't an enemy anyway) does not have the same issue.

3. Scuttled ships are stationary or extremely slow, spaceships are fast.

By the opposite token, a scuttled navy ship is not going to hurtle through the atmosphere, explode into the earth and leave a massive crater. A spaceship could though. Some sci-fi ships are of a size comparable to that of the asteroid that created the Chicxulub crater and caused the Cretaceous-Paleogene extinction event. This might be considered undesirable.

Even with smaller craft, this is a reason why real space ships have self-destruct mechanisms.

4. Scuttling a ship is dangerous, scuttling a spaceship much more so.

In the Big Scuttle of 1943, 9 Danish sailors were lost and 10 wounded, in the course of scuttling 32 ships. That's less than one death per 3 ships scuttled. In the depths of space though, scuttling a ship and then somehow surviving is likely either going to be impossible (nowhere to go) or no more difficult than destroying it (whee, super-fast escape-craft). Might as well blow the whole thing up, than be careful in the scuttling plans. (In the same Big Scuttle, 14 ships were taken undamaged, which would probably not have happened if they could have just blown them quickly).

5. Ships have lots of dangerous things that can blow up. Spaceships likely have even more.

They might essentially be a dangerous thing that can blow up, with a small living quarters attached. Self-destructing might be very much a matter of ceasing the continuous effort normally being put into not exploding. Scuttling a tank or howitzer would often be more comparable to sci-fi self destruct than naval scuttling, for similar reasons. Consider that the self-destruct sequence in Alien worked by stopping the cooling to the ore refinery and letting nature take its course. (Also why the process couldn't be aborted after a certain point, for extra drama).

6. Ships sink. Spaceships don't have anywhere to sink.

If you scuttle a ship it will sink, making recovery by the enemy likely more difficult than it is worth. A scuttled but unexploded space-ship though would likely just sit there waiting to be boarded. At worse the enemy could repair the scuttling damage, and best they would likely be able to salvage material and/or intelligence to their advantage.

In all, while both technological and cultural reasons for exploding an entire space-ship would depend on features of the fictional world-building, it's very much a sensible idea.

Answer 14

Self destruct is necessary to avoid having your assets fall into enemy hands. In Sci-Fi, boarding a vessel is usually surprisingly easy. In real life it usually is not. People would not generally attempt to approach an enemy battle ship in order to board and capture it, because it would be suicide.

Capturing a (space)ship provides the following potential benefits:

• You can attempt to repair the spaceship and add it to your fleet.
• You can learn about it's structural integrity and it's defense systems, stacking all future battles against similar hulls strongly in your favor.
• You can learn how to replicate parts of the enemy technology and incorporate them into your own devices.
• You can gain captives which, by interrogation, can divulge intelligence.
• You can search for classified machinery and data on the ship, hoping that the systems and protocols in place to destroy these failed due to battle damage (see enigma).
• You can learn about culture, habits, and weaknesses of the nation fielding the ship, e.g. look at how big the food storage is, and you know how long they can go without resupply.
• You can salvage parts of the ship to repair or build your own stuff.
• You can use the ship as a trophy for propaganda.
• You may even be able to trade the ship back to the enemy if it has some symbolic or other value to them.

On the sea, all of these can be prevented or severely delayed by sinking the ship in any place where the sea is too deep for divers. In space you can't sink a ship. Since you need excessive amounts of energy for propulsion, you just need to release that energy = atomize the ship.

You list the following alternatives to blowing up the ship:

1. Putting the ship into a gravity well, i.e. crashing into a moon, planet, sun black hole, etc - This offers no benefit to blowing up the ship. It still requires significant amounts of energy to change an object's course, gives the enemy time to react before the ship is destroyed, and can be prevented in various SciFi settings by tractor beams. In contrast, if you blow up the drive instead of using it to change course, the destruction is immediate and final, which is much preferable.
2. Radiate the ship - Nice idea, until the enemy builds radiation proof drones to capture the now undefended ship. You also need a way to radiate the ship, which might be harder than just blowing up the drive.
3. Fuse all electrical components - Requires the ability to fuse all electrical components, still provides the enemy with intelligence regarding the hull, can fail due to battle damage, still allows the enemy to learn more about your technology, still allows the enemy to salvage the ship for raw materials, etc. It's just a very bad idea.
4. Extreme rotational energy - Let's break the 4th wall: Many readers will have difficulties understanding this concept. There's also the issue us tractor beams and similar SciFi technologies which supposedly can undo this. Specialized scanners which scan the spinning ship for weeks may also be able to gain additional information. If the ship spins too fast it's ripped into parts, which are almost certainly bigger and more valuable than the parts left after detonating the drive. Spinning up the ship also needs control of the drive, which you could use to blow up the ship instead. Blowing up the drive and thereby atomizing the ship is much harder to undo.

So finally: Blowing up a spaceship is easy and it works. Other ways of scuttling a ship are difficult and do not deny the enemy from gaining an advantage as effectively as blowing up your ship does.

Answer 15

Scuttling a ship doesn't destroy it, but quite literally sends it to another dimension!

Very few ships are designed to operate successfully in that alternate dimension and return safely (submarines), so rescue operations are difficult and expensive, and too vulnerable to be undertaken during wartime.

If you don't have the technology to shift a spaceship to a relatively inaccessible dimension, then perhaps destroying it is the only suitable alternative.

Answer 16

I'm going to address a slightly different point - aside of material loss/gain or military loss/gain. On planet, you can generally walk off the side of the ship and float around and hopefully get rescued by your side or their side. Most warships don't have a lot of room for the crew of a loosing ship - especially a large one. There's also security issues. As a result, they can let you try to get to land, leave you to float, pick you up, call for someone else to pick you up... and all the while you have some degree of survivability.

Space is a different matter - not easy to breath vacuum and live and the cold/heat/radiation issues... Not good - especially floating in the middle of a bunch of battle clutter. On planet, warheads, torpedoes, missiles, simple bullets sink leaving you able to be approached. In space they would form a cloud of nasty around the battle site - again not really inviting for anyone to come pick you up.