10,000-pound M121 WWII bombs

This is taken out out of USO magazine “On patrol”. What are those huge bombs on the bottom left?

Those are 10,000 pound General Purpose bombs. We dropped a lot of them in Viet Nam to make helicopter landing zones. I have a picture of me sitting astride of one in the bomb dump in Canh Ranh Bay, Viet Nam. We pushed them out the back door of C-130’s on the wood crib you see in the picture with a parachute and barometric fuzes set to explode about 100 feet off the ground.

I found this on the website of the National Museum of the USAF:

During the Vietnam War, the USAF used 10,000-pound M121 bombs left over from World War II, to blast Helicopter Landing Zones in the dense undergrowth. As the supply of M121 bombs dwindled, the USAF developed the Bomb Live Unit-82/B (BLU-82/B) as a replacement. Weighing a total of 15,000 pounds, the BLU-82/B was essentially a large thin-walled tank (1/4-inch steel plate) filled with a 12,600-pound explosive “slurry” mixture. The designers optimized this bomb to clear vegetation while creating little or no crater, and it cleared landing zones about 260 feet in diameter – just right for helicopter operations. Since only cargo aircraft could carry them, C-130 crews delivered the BLU-82/B with normal parachute cargo extraction systems.


So this must be one of the largest “Special Purpose” ammunition ever developed? I wonder if, Pepper, has a “Helicopter Landing Zone” round in his collection :-) This might not fit on a SLICS display table?


Isn’t this bomb actually of post-WW2 vintage? The wikipedia says it was developed for the B-36, an airplane more in keeping with its girth and weight than the American bombers of the second war. Jack

Jack–The one I was sitting on was dated 1945.

An interesting Project CHECO report about M121 and BLU-82B use in South East Asia:


Was this bomb used in combat during World War II? I’m not a bomb person, but I am an airplane guy and until this thread had never heard of the M121. Jack

Here is a link to a great website that has pictures of all the different types of bombs used by the U.S., upto the 44,000 pounder.

scribd.com/doc/65567926/Amer … -1917-1974

The 15,000 Commando Vault (BLU-82) weapons were also sent to Saudi Arabia during Desert Storm and in Afganistan. They are dropped by the MC-130s operated by the 1st Special Operations Wing. They were designed originally (as I understand) to clear Jungle in Vietnam, but in Desert Storm about a dozen were dropped, initially to clear minefields. Some were also dropped in Afganistan as anti-personnel weapons (as I understand).

These weapons are filled with an explosive GSX slurry (ammonium nitrate, aluminum powder, and polystyrene) that degenerates under high temperatures and heat cycling. In fact, a weapon in a bunker at a desert storage area in California blew up in the late 1980s as I remember, on a Sunday morning. I have visited the resulting crater where the bunker use to be in the early 1990s. The bunkers in front and behing had the curved roof still standing, but the blast blew off both the front and back and scattered the munitions inside over a wide area. The bunkers on either side survived but the earth cover was blown off. The blast wave rolled over the curve side of those bunkers, but destroyed the flat front and back of the bunkers in front and behind. As a result of this another unstable Commander Vault was found at an overseas base that couldn’t be exploded in place and there was a rush effort to develop a remote drilling robot device to put a large hole in the bomb to inert and remove the slurry which was successful.

At the end of Desert Storm, the filled bombs in the Saudi desert were destroyed in place.

The largest bomb I know of in the USAF inventory today is the 30,000lb bunker buster called the Massive Ordnance Penetrator (MOP) or GBU-57. It is guided and designed to go after very deep and very hard sites and is the successor of the deep penetratorsdropped by the F-111s that took out the deep bunkers during Desert Storm. The guidence system allows the bomb to impact within a few meters of the target. The B-2 carries two of these weapons. The MOP was recently mentioned in the news media as the likely weapon of choice if the US went after the hardened nuclear sites.

Interesting Thread…


So you like the big ones ?

Here I am trying to get the U.S. biggest bomb ever for my collection. I stand 6 feet 2 inches. Do the math.

Aberdeen APG, I tried to enlarge this photo but it did not work.