These things are TOUGH MOTHER FUCKER that go big boom. -Max http://www.fas.org/nuke/guide/usa/bomber/n19980326_980417.html EIELSON AIR FORCE BASE, Alaska (AFNS) -- A B-2 Spirit bomber dropped two B61-11 bomb shells to test their improved ground penetration capability March 17 at the Stuart Creek Impact Area, 35 miles southeast of Fairbanks. The tests here were designed to measure the nuclear bomb casing's penetration into frozen soil and the survivability of the weapon's internal components. These were the final two tests needed to certify the weapon system as operational. A team excavated the two unexploded dummy bombs and took careful measurements of their angles and depth of penetration into the soil, which were 6 and 10 feet, according to Ellsworth Rolfs, a B61-11 program test manager. The shells were sent back to Sandia National Laboratories in New Mexico for full analysis of how the simulated internal components fared in the impact. ... "The test unit casing didn't rupture in any of our tests, including drops through concrete from 40,000 feet," he said. "We fully recovered all test units 100 percent intact."