SSD
The hangar roof collapse at Woodford was caused by a botched roof extension to accomadate the AEW Nimrod. When the extension was added all the load was being carried by the asbestos roof panels. HSE rules dictated that the asbestos panels had to come out and BAe took the opportunity to insulate the roof at the same time. A combination of the additional weight of the scaffolding in the roof and the lack of rigidity from the roof panels caused the roof to collapse.
In the hangar at the time was the Lanc, two unsold 748's and a fire damaged Nimrod (damaged on take off from St. Mawgan IIRC, and eventually scrapped, but thats another story). The roof collapse missed the Nimrod and both 748's and virually cut the Lanc in two. Several of the roofers where seriously injured and a BAe inspector was killed, scallded by a broken steam pipe.
If the roof collapse had happened twenty minutes earlier, then the injury list would have been much higher, it collapsed during the lunch break.
Not one of my best memories of Woodford.