Bin Laden recounted his experiences at Tora Bora on an audiotape that aired on Al Jazeera in 2003. He recalled that, on the morning of December 3, heavy U.S. bombing began around the clock, with B-52s dropping some 20 to 30 bombs each.
unwind. 1  to wind off or undo (something wound) 2  uncoil. 3  to straighten out or untangle (something confused or involved) 4  to make relaxed, less tense, etc. 5  to close out (a position in a securities or commodities trade) to sell (a stake in a company, business venture, etc.)
Unbalance is a radial force and produces a vibration frequency equal to shaft speed. The Radial force can sometimes also produce a vibration in an axial direction, especially in overhung or cantilevered rotors. In these rotors the axial vibration may be even greater than the radial vibration. The radial force causes the shaft to deflect, producing an axial direction vibration in the bearings. Normally, unbalance will produce a 1x or shaft speed vibration that is 80 percent or more of the total vibration. If 1x vibration is less than 80 percent, suspect other problems in addition to the unbalance.