We had a visit from the NRPB, CAA and the AAIB (mob handed!) following the loss of PA103 asking how much DU could possibly be fitted. The answer being no idea! It was used to mass balance the elevators, outb'd ailerons IIRC upper rudder and could also be found bolted inside the outb'd nacelles to stop or rather damp out 'pod nod'. The latter depending on the mod state because the other option, would be to do away with the nacelle weights and fit a damn great block of Ti at the back of the exhaust plug.
I don't think it was ever recovered, more than likely scattered over several thousand square miles of Scotland.
