BIIIGGG bomb - what's TMH doing about it ?

[Bert Coules]

Who or what is TMH?

[Bert Coules]

Forget that: I've just fallen in...

[Onetap]

Survey report here;

bombs contain 1400 tons of TNT which is thought to be still viable but stable.

The concern is the cluster bombs, which are fused. The fuses may have degraded and become sensitive. The fuse was screwed into place by a propellor device after the bomb was dropped from an aircraft, so it was safe (by 1944 standards) to transport fused bombs. There also WP which may account for some fires reported around the wreck; WP burns in air. The usual fruit loops claim it may have chemical munitions as well, but there's no evidence.

All the experts recommend leaving it alone.

[Derek G.]

It's a typo for "Sheer mess".

Derek G

[Londonman]

It would take out Sheerness, so not all bad.

and even better............ about a third of Essex

[Roberts]

Remembering the fuss about the oil spill in the sea off the southern states of USA I suggest we sue the Americans>

Robbie

[dennis]

I thought the only high explosive cluster bombs of that period were German butterfly bombs. Aren't theses allied incendiary cluster bombs?

[The Medway Handyman]

No problem BC :-)

[The Medway Handyman]

Thats no way to talk about me Bob!

[The Medway Handyman]

[The Natural Philosopher]

Extraordinarily good point.

[tony sayer]

You learn summatt here every day!, I always wondered why the used them I assumed it was to generate some electrical charge;!...

[David WE Roberts]

Sounds reasonably surfable. Not quite twice the height of the highest Severn Bore. Could be part of the grand opening ceremony for the 2012 Olympics?

[dennis]

There were a number of ways to ensure the bomb didn't arm until it was clear of the plane. The prop was one, a length of wire fasten to the bomb rack was another.

What got me was that it was originally planned to arm the Hiroshima bomb before the plane took off and it was only a few crashes the week before that changed that plan.

[ARWadsworth]

:-)

[ARWadsworth]

What if it needs a wireless doorbell fitting?

[Andy Dingley]

There is a diffference between "arming" and "safing". If the fuze is a sophisticated design, it may be possible to keep it safe with a safing wire inserted through some moving part. If it's a cheap design though, and cluster bombs generally were, then this isn't applicable or reliable. In that case, the detonator needs to be kept physically separate from the striker, by enough distance that a crashing plane won't bring them together. The classic way to do this is a screw thread and a propeller. This cheapness of fuze manufacture on individual cluster munitions is what gives them their perennial unreliability problem.

Going the other way, a "render safe" procedure for a bomb or landmine might be to have the wire inserted, but "defuzing" requires the detonator to be physically separated. A "rendered safe" munition can't be handled quite so carelessly as a "defuzed" one can - in particular it may not be possible to transport it, so it might then have to be destroyed in situ (you can carry it away from buildings, but you can't truck it away to a bomb cemetery in bulk). Apart from the few that can't have either done to them, many ordnance devices (esp. landmines) can be either rendered safe or defuzed, but not both.

Hiroshima (Little Boy) was always intended to be armed (actually to have the pit and capsule inserted) in flight. For a gun-type device, this was relatively practical (although difficult in an unpressurised compartment at altitude).

Later implosion-type (Nagasaki type) bombs (Mk 4 & Mk 5) had "in- flight insertion" too, even though this is a much more complex task for an implosion bomb, because there's much more explosive "works" in the way. The bomb casings were flat-nosed with obvious nose doors. They could only be carried by aircraft like the B50 or B36 where there was crew access to the bomb bay. The later Mk 5s had "automatic insertion", which was basically the same thing, but driven remotely by an electric motor. These were in service until the early '60s (it seems the RAF Valiants were the last to use them).

[Steve Firth]

result in damages running into tens of pounds.

[dennis]

Not according to the guy that armed it. It took him a few hours to do it in flight IIRC. There were three detonators and other gubbins to fit.

[John Williamson]

*That* much?