Others have already linked to Wikipedia's article about the crash
, with one guy saying "sounds like a wing fell off". Reading the article, that seems fairly close to the mark, though not quite right. Here's a summary of what happened to the bomber:
The bomber was on an "airborne alert mission", meaning that it was carrying live nukes while flying on a route and schedule that would make it ready to perform a nuclear attack on the Soviet Union on short notice. (This was part of a program called Operation Chrome Dome
.) While it was refueling from a tanker over North Carolina, the tanker crew told the bomber crew that the bomber's right wing was leaking fuel. The bomber broke off from the refueling, informed ground control, and were ordered to fly offshore and hold to burn off most of their fuel load, to reduce the risk of an emergency landing. However, on the way to the holding point, the fuel leak rapidly worsened and became critical, and the plane was then ordered to land immediately. During the descent toward the field, while passing through 10,000 feet altitude, the pilots found they could no longer keep the aircraft under control. The captain ordered the crew to eject; those who survived reported that the plane was still intact when they last saw it. Once the airplane went out of control, it must have gone into an uncontrolled spiral dive, a "tailspin"; that's what frequently happens to a flying airplane when control is lost. Such a dive is often fatal for the airplane long before it reaches the ground; the aerodynamic stresses increase so fast that it breaks up in the air.
From the sound of it, there was some sort of structural failure in the right wing which got rapidly worse. The wing did not actually fall off while the pilots were inside, but the failure became so bad that they couldn't maintain control and were forced to bail out. Unfortunately, even this article puts so much focus on what happened to the nukes that the important question of what caused the bomber accident in the first place is ignored. It would be nice to see what the Air Force's accident report has to say on this.