fish_boy said:
I read that the new US bomb is based on the British "Tallboy" 12,000lb (5.44 tonnes) bomb of WW2. This weapon could penetrate around 5m of reinforced concrete or up to 50m of earth when dropped from 20,000 feet.
Even if the US "Bunker buster" was dropped from (as per the original Tallboy design) altitude of 40,000 feet these figures would alter much, given the bomb achieves terminal velocity from 20,000 feet.
Destroying a target dug out of a mountain made of granite is a different order of magnitude to knocking out a U-Boat pen.
Being Americans, I am surprised they didn't bypass the Tallboy and go straight for the grand Slam bomb - 10 tonnes. Maybe they didn't want to have to ask the British if they could borrow a Lancaster.
It's more like a supersized Durandal.