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30,000-Lb. Bomb On Fast Track For Deployment
coondoggie writes "Published reports today say the Pentagon is rattling swords in the direction of North Korea and Iran by speeding the development a 20-foot, 30,000-lb bomb known as Massive Ordnance Penetrator. This weapon is intended to annihilate underground bunkers and other hardened sites (read: long-range missile or underground nuke development) up to 200 ft. underground. The Defense Threat Reduction Agency, which has overseen the development of this monster since 2007, says it is designed to be carried aboard B-2 and B-52 bombers and deployed at high altitudes, from which it would strike the ground at speeds well beyond twice the speed of sound to penetrate the below-ground target." Reuters has more specifics on the MOP's chances for deployment by 2010, and the detail that the bomb's load of explosives weighs in at 5,300 lbs.
Though true, what's interesting about this one? I don't mean that entirely as a rhetorical question: it's possible there really is something interesting here. But I haven't seen a good summary.
Is it just, take a normal bomb, make it really really big, and slog through some tedious but mostly straightforward engineering challenges to get the thing to work? Or is there something that, at a conceptual level, is different when you get to bombs of this size?
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
This is really a reinvention and extension of 1940's British technology. Barnes Wallis (of the bouncing "Dam Buster" bomb fame) designed a 5 tonne bomb (Tallboy) in 1943. The larger 10 tonne bomb (Grand Slam) was introduced in early 1945. It was dropped from a Lancaster bomber (by 617 squadron - the Dam Buster squadron) from about 20,000 ft and was close to sonic (320 m/s) when it hit the ground. It was designed as a penetrator, only detonating when well underground. It was used with devastating effect against the German U Boat pens, canals, bridges and viaducts where the "earthquake" effect of a deep explosion undermined foundations. The Grand Slam used 4,144 kg of explosives (Torpex)which is considerably more than the heavier bomb proposed by the US DoD with an earth penetration design depth of 40m. I would imagine that the higher impact speed of the US bomb requires a much stronger casing, but I am surprised at the small ordinance load. It is interesting to note that (as with much British technology) design data for the Grand Slam was shared with the US and a US version was made, but not (as far as I am aware) used in WWII. RobHart
While we're at it, also have a look at this Russian thingy. It's thermobaric, and thus very different in its intended use (not a bunker buster, but what you'd use to clear a large network of caves or underground tunnels with surface exits in one sweep), but of the same magnitude of raw power.
They should write it's power output in terms of sun, in which case it looks really puny next to nuclear. For example, the Tsar Bomba (largest human utilized explosive device, which was detonated at half the possible yield to prevent fallout) actually got into whole number percentages:
"Since 50 Mt is 2.1*10^17 joules, the average power produced during the entire fission-fusion process, lasting around 39 nanoseconds, was about 5.4*10^24 watts or 5.4 yottawatts. This is equivalent to approximately 1.4% of the power output of the Sun.[9]" (Wikipedia).
Ever heard of a kinetic penetrator? It is a type of ammunition used in the main gun of tanks. It contains no explosives, but rather a very dense, arrow-like projectile which uses its high speed (and thus its kinetic energy) for all its destructive power. Kinetic energy weapons are generally weapons that rely solely on their kinetic energy for their destructive power.
Other more sci-fi types of kinetic energy weapons would be rail guns and coil guns.
Evelyn Waugh - Letter to His Wife - 31st May 1942
No.3 Commando was very anxious to be chums with Lord Glasgow, so they offered to blow up an old tree stump for him and he was very grateful and said don't spoil the plantation of young trees near it because that is the apple of my eye and they said no of course not we can blow a tree down so it falls on a sixpence and Lord Glasgow said goodness you are clever and he asked them all to luncheon for the great explosion.
So Col. Durnford-Slater DSO said to his subaltern, have you put enough explosive in the tree?. Yes, sir, 75lbs. Is that enough? Yes sir I worked it out by mathematics it is exactly right. Well better put a bit more. Very good sir.
And when Col. D Slater DSO had had his port he sent for the subaltern and said subaltern better put a bit more explosive in that tree. I don't want to disappoint Lord Glasgow. Very good sir.
Then they all went out to see the explosion and Col. DS DSO said you will see that tree fall flat at just the angle where it will hurt no young trees and Lord Glasgow said goodness you are clever.
So soon they lit the fuse and waited for the explosion and presently the tree, instead of falling quietly sideways, rose 50 feet into the air taking with it 1/2 acre of soil and the whole young plantation.
And the subaltern said Sir, I made a mistake, it should have been 7 1/2 not 75. Lord Glasgow was so upset he walked in dead silence back to his castle and when they came to the turn of the drive in sight of his castle what should they find but that every pane of glass in the building was broken.
So Lord Glasgow gave a little cry and ran to hide his emotions in the lavatory and there when he pulled the plug the entire ceiling, loosened by the explosion, fell on his head.
This is quite true.
I can think of no good ways that they are a direct threat but the fact they would trash the northern half of South Korea in the first half hour of a hot war is one deterrent. They've been training massive amounts of long range artillery of Seoul for years and that would be the first thing to go
That artillery wouldn't last very long if a shooting war broke out. We know where a lot of it is and the remainder would reveal itself as soon as they fired the first volley. Between counter-battery fire and US/ROK airpower those artillerymen would have a short and exciting life once the shooting started. The destruction of Seoul isn't very likely -- it wouldn't escape undamaged but it wouldn't be a modern day Dresden either.
their likely ability to overrun the DMZ
This will sound counter-intuitive but we actually want them to overrun the DMZ. We pulled the bulk of our forces back from the DMZ many years ago. The current plan calls for a counterattack into North Korea to cut them off/go after Pyongyang rather than meeting them at the DMZ and fighting for every inch of ROK soil. It's easier to destroy their forces if they are out in the open conducting offensive operations. As Patton said during the Battle of the Bulge, "Let's have the guts to let the Krauts go all the way to Paris. Then, we'll cut them off and chew them up."
China seems to use NK the same way a redneck likes to keep a slobbering pitbull on a chain prominently on display in his back yard. Sure you can just shoot the nasty thing dead but it won't be the end of it and it isn't much use talking to it. The redneck is the one you have to reason with.
ROFL! That's the best analogy ever :)
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
They used them for psyops in Afghanistan. Had some Taliban holed up in a valley, some spec ops team called for fire support. So the B-1s fly through the valley supersonic while dropping bombs... and hitting everything with its sonic boom. The spec ops dudes said 'I knew that was coming, and I still shit my pants' or something to that affect.
Anyhow, the B1's bombbays are probably too small in one dimension to fit the MOP.