The famed Russian thermobaric bomb, that is.
The Russians, astoundingly, didn’t actually release a lot of technical specifications about the weapon, aside from it’s weight, and the implication that they dropped it out of a Tu-160 (although there’s some debate about that last bit—the weapon appeared more suited to delivery by a cargo plane)
But I thought I’d ask here, in the hopes that someone would have a better way of ballparking it than me. Can anyone help?
Oh, hey…my first post of 2009! ::cue Kermit yay::
Why not start off the new year with some WAG and back-of-the-envelope calcs.
Leaving aside all the statements about “nanotechnology” let’s assume that the Russian device is very similar to the American MOAB - it’s a thin steel container filled with several tons of explosives. Let’s also assume that the density of the filling is about the same and that both the Russian device and the American device have a similar percentage of the total weight as explosive.
The MOAB is about 30 feet long and 40 inches in diameter (from Wiki). It has a total weight of 22,600lbs and a filler weight of 18,700lbs. This gives a total device density of about 86.3 lbs/cu ft, and the ratio of total weight/filler weight is about 1.2.
The Russian device, according to Wiki, has a filler weight of 7100kg. Using that same factor of 1.2 gives a total estimated device weight of 18,800lbs.
Following some of your links leads to video of the Russian news story which shows both film of the device being dropped and animation of it so we can get an idea of the proportions. Freezing this video:
At about 1:45 shows that it’s a big fat cylinder with a widget hanging on the right side, I’m assuming that’s the parachute delivery system and so I discounted that from my subsequent calcs. The length of the main body appears to be about 2.5 times the diameter which for a plain cylinder gives a volume of 1.96D^3.
Assuming a density of 86.3 lbs/cu ft (same as the MOAB) and with our estimate of the total weight of the device (18,800lbs) we can get a diameter of 4.8 feet and a length of 12 feet. Remember that’s just for the main body of the device, not the overall length but you can estimate that from the same video.
Feel free to pick away at my assumptions 
Oh and I agree that the video doesn’t look like it shows that bomb being dropped out of that bomber - the video of the device going out of a plane with the drogue chute deploying really looks like what you’d see filming something rolling off the ramp of a big cargo plane, not what you’d see of something dropping straight down from a bomb bay.
AWEsome! I am in your debt…thanks! 
