Our Hero (OH) has finally triumphed over the mob of saber wielding monkey guardians. He blows down the doors leading to the heart of The Evil Mastermind’s (TEM) command center/chamber of love, but when the dust settles, OH is greeted by a loud woosh and the hot exhaust of TEM’s escape pod. Their eyes lock in mutual loathing, and as the pod blows through the ceiling and arcs across the sky, OH can hear TEM’s taunting laughter, because when TEM ordered his escape pod he chose the one with the optional exterior PA system for just such an occasion. Before OH can think of tracking down TEM however, he suddenly has a more immediate problem on his hands: that dreaded soothing female voice announcing “the self destruct sequence has been activated. Eight minutes before total annihilation…”
So, has anything every actually been built with a self destruct system? I can understand the various motivations to do so (destroy intellegence, deprive enemy of captured resources, collateral damage), but given the additional engineering/material costs, has anything been deemed worth the expense? Nuclear subs? Spy planes? Chocolate factories?
No cite, but I’m fairly sure the data recorders on recon birds can be fried at the flip of a switch. The D-boys/Rangers that secured the Black Hawk crash sites in Mogadishu dropped some pretty horrid grenades into the wreckage after they got everyone out.
Didn’t many military naval ships has a method for scuttling? Opening up the seacocks, planting charges, etc…? I realise that the explosives can be seen as an afterthought, but building in seacocks, a system to flood the ship, can be seen as a self destruct system of sorts.
No cite, but I remember reading that the CIA U-2 Powers flew over the Soviet Union had a self-destruct system. Powers, if I remember correctly, thought he activated it before he bailed out but obviously it didn’t work. If I remember correctly, there were concerns about the pilot getting far enough away before the plane blew up-and consequently concerns whether the pilot would activate the sequence before he bailed out. In the one case it mattered, the system didn’t work. (recognizable pieces of the aircraft were displayed at a news conference).
Military intelligence type aircraft have a “self-destruct” to wipe out the hard drives on their data gathering and communication computers. When the Chinese forced down that Navy intelligence aircraft, they were able to destroy or wipe clean the hard drives, but did not have enough time to destroy all of the paper manuals or smaller devices themselves - the crew was supposed to shred and dump them out before landing. I remember reading that just by looking at the antenas on the plane the Chinese could figure out what information, and approximately how much detail, the Navy was getting. At Bell Labs, some of the pc’s had a device attached to the side; if the hard drive was removed without the proper code entry, a magnetic pulse would be generated to wipe the disk. It was kind of funny there. Just like large companies, they would have internal classes on things like Word or Powerpoint. Some of the pc’s in the classroom were re-used from other work. When class was over, and before you were allowed to leave, armed guards would come in with a cart and physically remove the hard drives from some of the pcs the students were using. They had been used before for government secret stuff, and were still under tight control.
Minor nit. Don’t the SRBs simply light the other end? (I think a solid rocket booster can burn from either end, can’t it?). I don’t think they self-destruct, they just quit moving forward (and hopefully plunge into the ocean).
Sorry, no cite. I was told this by and ex-NASA worker.
The SRB’s have a hollow center their full lengths. They burm from the inside out, not the bottom up. The destruct feature is an explosive cord running lengthwise along the case, which ruptures it, relieves the internal pressure and stops the motor from producing thrust, although the fuel continues to burn to exhaustion.
The purpose of a range safety system on-board a launch vehicle is the termination of powered flight, or thrust, not reducing it to tiny pieces with a big explosion. The idea is that after powered flight is terminated, the remains of the launch vehicle will follow a ballistic trajectory into a safe impact area. The range safety officer (guy/gal with the big red button) has computer systems that provide continually updated predictions of where the debris would land if the engines failed or the launch vehicle suffered a structural failure. Many expendable launch vehicles will automatically self-destruct if they detect a catastrophic problem like structural failure. This can happen if the guidance system fails and excessive aerodynamic loads cause the vehicle to break up. This happened to Ariane V when a software problem resulted in simultaneous failure of all the on-board computers.
The very first use of a Self Destruct mechanism in a science fiction movie that I know of was in the underappreciated Robinson Crusoe on Mars. It’s a surprisingly good flick, if you make a couple of allowances, and it managed to sidestep a lot of cliches. It sidestepped the “self destruct” cliche before it even began. Usually the self-destruct is used in a tense, dramatic, and utterly unrealistic climax sequence where the mechanism has been activated when the hero is still tragically close, for some reason (as in the OP), and either has to escape or disable the mechanism. In RCoM the hero uses the self-destruct to destroy his still-orbiting vessel, which might attract the attention of the prowling and dangerous aliens (just as the Swiss Family Robinson blew up the remains of their ship, after salvaging what they could, to avoid attracting the attention of pirates). He presses the “self destruct” button from his rem,ote console, and the ship, which is far awaty, blows up with a muffled crump. It’s the most realistic and believable self-destruct I’ve seen in any movie.
Usually, as I say, the Self Destruct device is used for a hypertense, artificial situation. The SF TV-movie Something is Out There even poked fun at this. The Earth Guy and the Beautiful Female Alien (played by one of those d’Abos) are trying to get away from and destroy the Evil Alien Creature aboard the ship.
Earth Guy: Don’t you have a self-destruct built into this ship?
Beautiful Alien Female: Why would we want to do that?
No. The SRBs have a ring of det cord around the middle that basically cuts them in half. With the pressure containing the combustion of the solid fuel suddenly released, they go foom pretty spectacularly.
Actually, the det cord runs down the side of the SRB, along its entire length. When it blows the entire SRB comes apart along its entire length instantly. In theory, when the pressure and heat of the combustion chamber is released, the remaining fuel stops burning. The shuttle also has a line of det cord running down the length of the external liquid fuel tank to cut it open and disperse its fuel remotely as well.
Furthermore, SRBs don’t burn from the end. They burn from the center - they’re basically hollow tubes of fuel, not solid cylinders. The ignition system is actually at the top, and combustion takes place along the entire length of the booster throughout the flight. It is possible with this kind of rocket to have a thrust-temination system which consists of blowing off the nose of the rocket, letting the exhaust out of both ends, and that may be what pullin’s NASA friend was thinking of, but the shuttle doesn’t use that system.