Somewhere around 1973 or 74 we had a HAS1 flew into the cliffs at night on a casex, hidden in the blind arc and plot slippage was believed to have been a factor: 824NAS. Somewhere west of Predannack, IIRC: the cliff was 210 feet AMSL, they were in the jump at 200ft RadAlt. I had to launch with the total holding of black powder extinguishers from Culdrose to drop off to extinguish the MGB on fire: all 25-30 of them.
I'll look up the date tomorrow.