self-destruct mechanism

[McPerth]

The problem is that crippling the ship generally means the power plant, maneuver, and jump drives no longer work. That in turn makes it pretty hard to use them to accomplish a self-destruction.

True, and leaving it fuelless acomplishes all at once...

On the other hand, it won't take a lot of hydrogen on the whole to flood the ship sufficiently for a nice fuel-air mixture to detonate. Since the ship would have lots of separate tanks rather than one big one, it's going to be likely that one or more survived. You'd only need battery or emergency power to operate the valves and sensors. Adding extra oxygen only makes it even easier to do.

The mix doesn't even have to be that precise to get an explosion, and if you're off a bit you still get an nice fire that burns the compartment out.

Of course, in the OP scenario wouldn't it just be easier to set the ship on a "death spiral" into a gas giant or star and have some sort of control disable that means the boarders either get off or ride the ship down to its destruction than some sort of blow the ship up device?

Another thing to keep in mind is that a ship being boarded is likely to be in vacuum, be it due to battle damage or to standard practice to avoid explosive decompression (probably both). A hijack attempt, though, is another matter...

 

[whulorigan]

. . . P-P fusion in a transportable form would need some Deuterium doping to make it work.

What are your thoughts behind this? Normally P-P fusion produces the deuterium that it needs.

1. [ p + p ==> d + e⁺ + ν_e ] x2
2. [ d + p ==> ³He + γ ] x2
3. ³He + ³He ==> ⁴He + 2p

p = proton
d - deuteron
e⁺ = positron
ν_e = electron neutrino
γ = gamma photon
​

Or are you speculating from a technology standpoint that an initial doping of deuterium would allow alternate fusion reactions to start at a lower temperature (d+d and or d+p) and help produce the energy needed to step up to P-P fusion?

 

[Lycanorukke]

What are your thoughts behind this? Normally P-P fusion produces the deuterium that it needs.

Yes and no. The catch is that stage 1 (p + p ==> d + e⁺ + ν) - Beta plus decay - is a fairly rare occurrence.

Most of the time it simply splits apart again into 2 protons.

p + p -> ²He -> p + p

Once you have the deuterons, stages 2 and 3 are almost instant.

The reason it works in the sun is due to the sheer amount of fusing hydrogen. In a reactor when the density is probably a lot less, it would be easier to slip in some deuterium to boost available deuterium. Of course you could always handwave with nuclear dampers.

Or are you speculating from a technology standpoint that an initial doping of deuterium would allow alternate fusion reactions to start at a lower temperature (d+d and or d+p) and help produce the energy needed to step up to P-P fusion?

That what I am thinking with the 'start' mode. Bootstrap the reactor chamber temperature up in a series of stages (D/T, D/D, D/p, p/p) as opposed to trying to go from room temperature to a bajillion degrees in one go.

The same with 'Park/Idle mode' - reduce stress on the reactor when full power is not required, but still have it running if full power is needed quickly as opposed to a cold start.

 

[Carlobrand]

If you're near a world and have some maneuver capacity, point it at the world and set the computer to provide continuous thrust before abandoning.

 

[McPerth]

If you're near a world and have some maneuver capacity, point it at the world and set the computer to provide continuous thrust before abandoning.

If the world in inhabitated collateral damages may be hard...

Remember they are the ones likley to rescue you after abandoning the ship (if anyone does).

 

[Enoki]

If you're near a world and have some maneuver capacity, point it at the world and set the computer to provide continuous thrust before abandoning.

I suggested that. But, you don't even have to point it right at it (or where it'll be), so long as your course takes you close enough for gravity to do the rest. But, the system star might be a better option... :toast:

 

[Enoki]

Another thing to keep in mind is that a ship being boarded is likely to be in vacuum, be it due to battle damage or to standard practice to avoid explosive decompression (probably both). A hijack attempt, though, is another matter...

Except "explosive" decompression is largely a myth, even in space.

https://www.youtube.com/watch?v=4yG2h1aDB6k

By the time you get to major damage from a decompression the explosion causing it would be far more dangerous than the following decompression.

 

[Carlobrand]

I suggested that. But, you don't even have to point it right at it (or where it'll be), so long as your course takes you close enough for gravity to do the rest. But, the system star might be a better option... :toast:

Oop, sorry, missed that. I considered the system star, but it's generally too far away to be useful. They've got a lot of time there to figure out some intervention.

If the world in inhabitated collateral damages may be hard...

Remember they are the ones likley to rescue you after abandoning the ship (if anyone does).

Depends. Even on our billions-and-billions world, odds are pretty good you'll either hit water somewhere that it won't matter or hit open territory. You'd probably have more problems with them trying to prosecute you for what almost happened than for what did happen. But, fortunes of war - assuming it's a war. If it's not, then why are they permitting hijackings in their space? They should have had a system patrol component that could have come to help you. So, their fault anyway.

 

[McPerth]

Except "explosive" decompression is largely a myth, even in space.

https://www.youtube.com/watch?v=4yG2h1aDB6k

By the time you get to major damage from a decompression the explosion causing it would be far more dangerous than the following decompression.

Well, what I understand as explosive decompression is not the ship exploding, but the hole sucking many things (or people) and the air current to it producing damages inside the ship.

Another reason to put your ship into vacuum in combat would be to minimize the fire risk.

In any case, I always assumed it was a standard practice to put your ship (or at least most of it) in vacuum when readying for combat.

Even a long battle as the one told about the Bard Endeavour is likely not to be countinuous combat, but a series of skirmishing, allowing the ship to short time of presuring it for crew's rest (or to have some resting areas presured). See that in the incident I of AHL the whole ship is in vacuum.

 

[McPerth]

They should have had a system patrol component that could have come to help you. So, their fault anyway.

I'd wish you good luck at the court if you try this :devil:... In the best case, you'll be stranded in the planet for some time while the trial is performed.

 

[Ran Targas]

Could you just open all the bulkhead doors to engineering and flood the ship with reactor plasma? Not much would withstand exposure to contact with super heated hydrogen and helium at fusion temps. The hull may survive but only as a hollowed out hulk.

Also, what about scuttling charges? I designed a military courier that carried a kiloton sized charge just for this purpose.

 

[aramis]

Could you just open all the bulkhead doors to engineering and flood the ship with reactor plasma? Not much would withstand exposure to contact with super heated hydrogen and helium at fusion temps. The hull may survive but only as a hollowed out hulk.

Also, what about scuttling charges? I designed a military courier that carried a kiloton sized charge just for this purpose.

Plasma isn't all that energy dense. In part, because it's generally not very dense. You're probably using less than 2 kg of fusing plasma to generate the output...

Even at 15,000°C, that's still (checks, specific heat around 21 kJ/kg/°C)... 31.5 MJ... spread out over the entire surface area of the engine compartment first...

The penetration value drops precipitously almost instantly.