Self Destruct Sequence

I was perusing Wikipedia and in the article about Grissom’s ill-fated first flight Liberty Bell 7 (the one that sank) it says this about its eventual recovery:
After Liberty Bell 7 was secured in the deck of the recovery ship, experts removed and disposed of an explosive device that was supposed to detonate in the event of the capsule’s sinking but which failed to explode**

First I’d heard of this. If true, I assume it was so the Russkies couldn’t get their commie hands on one…

WWII torpedos had a self-destruct mechanism included. If they reached their ‘end-of-run’ (out of fuel) without having hit a ship, they would explode. Presumably this was so that there would not be live torpedos floating around in the area where the submarine was.

FASCAM Artillery rounds have a self-destruct sequence.

FASCAM rounds scatter a minefield via field artillery. Nasty little trick for denying enemy troops mobility.

The mines self-destruct after a given time period.

There is also an aircraft-deployed system or two that does the same thing.

Target drones used by the Air Force often have self destruct systems. Some of the drones are actually older fighter planes, flown by remote control for testing purposes. If one of them is damaged enough to make it unrecoverable, it will be destroyed over the test area.

Ah well, we British bombed them,
something I learned from immense hostility from one relation of a family I stayed with in about 1967.

With hindsight, I think she probably lost a future husband.

I accept no responsibility for the antics of my forebears, but I’ll quietly say that I would have done the same in their place.

Shelled - assuming you are referring to Mers-El-Kebir

IIRC he had a coin with a spring-loaded needle. Hopefully no one ever got them mixed up and bought a candy bar with one…

This isn’t true. The Lockheed U-2 “Dragon Lady” reconnaissance aircraft has never been equipped with a self-destruct system. Such a system that would effectively dismember the craft would require a serious weight penalty and would be of little use; if one were to be shot down or fly out of control the fall from 60k+ feet would pretty much demolish the major structure (as with Power’s plane) and no reasonable charge would be able to completely disintegrate the major components of the aircraft like engines and avionics. There was a small charge on the film cannister (thus eliminating information that would tell the opposition how high the plane was flying) which Power’s failed to detonate, but by his own testimony he has no recollection of the hit (if in fact the plane was struck, a point about which there still is no consensus). Power’s first reported memory after the flight anomoly was being out in free fall, having already ejected or having been auto-ejected. I don’t recall whether Power’s was given a cyanide pill or not, but the notion that he was required to use it if captured is hooey; such a policy has never existed even in the darkest intelligence agencies.

As for missiles, it depends on the function. Operational ICBMs and SLBMs do not have range safety/flight termination systems on the basis that once they’re launched they are supposed to proceed to target without further instruction. It’s still theoretically possible to abort a flight by inducing premature staging and thrust termination (which blows open ports in the upper dome of the stage to prevent it from raming the subsequent booster stages or payload after stage seperation) but you end up with a large motor burning at both ends, which is not something you care to have land in your back yard. Test flights are equipped with a range safety destruct system which blows open/apart the booster and payload into a statistically predictible debris pattern should the flight become uncontrolled or fly out of the expected flight path. Other missiles, like Tomahawk cruise missile, the defunct Spartan booster-interceptor, and the Patriot, have self-destruct capability, either as a seperate subsystem or by prematurely detonating the main charge. Torpedos do have destruct systems (again, detonating the main charge) which can be used if they’re being wire-guided; otherwise they just run until their battery/solid prop runs out, and then a safe & arm switch is supposed to disable the main charge.

Regarding the STS Solid Rocket Boosters, I quote from Space Shuttle: The History of the National Transportation System by Dennis R. Jenkins:
Originally, both SRBs and the ET [external tank] were fitted with explosive charges capable fo destroying the vehicle. The ET system was deleted beginning with with ET-80 since it was felt the vehicle was sufficiently far downrange not to present a threat at that point – the SRB systems are retained…The ET range safety package consisted of linear shaped charges on botht he LO2 (8 feet long) and LH2 (20 feet long) tranks on the ET. The SRBs have a linear shaped charge running hte length of each booster. The SRB charges split the SRB casing open, effectively terminating thrust. The charges are linked together in such a way that if one RSS package receives a destruct signal, the signal is routed to all packages to ensure complete destruction of hte vehicle. On STS-33/51-L, the RSS was commanded to destruct the SRBs approximately 30 seconds after the breakup of Challenger, and the ET RSS was recovered intact, os neither system played any role in the accident.

The STS Orbiter neither has nor can be readily fitted with a destruct system; when aero and thermo loads exceed design capability, it comes apart like a cheap gold watch, and there’s really no way to predict the debris pattern, particularly on re-entry. The Shuttle is supposed to have enough cross-range (ability to glide in a broad path) to maneouver to safety even with the loss of the Shuttle Main Engines (SME) and this was the theory under which the requirement for a launch abort/eject system was eliminated, but the reality is that an abort sequence occuring early enough to require a Return-to-Launch-Site (RTLS) or East-Coast Abort Landing (ECAL) is laughably complex and very high risk; fortunately, the only post-launch abort occured on STS-51-F with an Abort-to-Orbit (ATO) manoeuver.

I believe US Navy submarines are fitted with scuttling charges; these won’t completely destory the sub–nothing short of a nuclear blast could disintegrate a submarine–but they do breech all bulkheads, the idea being that the command officer will scuttle the sub in an ocean trench or other inaccessibly deep area for future recovery, a la Project Jennifer. I don’t recall reading of any specific systems for WWII subs; I think the plan there was simply to open all ballast valves, point the dive planes down, and send the sub to below crush depth (>200 meters) where it would be unrecoverable by the technology of the day.

On a lighter note, my favorite cinematic destruct sequence is the one in Galaxy Quest, where Tim Allen and Sigourney Weaver are desperately trying to figure out how to cancel the auto-destruct sequence to no avail…only to discover that it automatically stops at “00:01”…because that’s what it always does in the show.