I remember an advert in Resale Weekly (was it around the late 80s / early 90s?) -
'For Sale Euclid R15 kept undercover last 20 years' together with a great pic of an R15 dumptruck partially uncovered when an old waste tip was being removed!
Not sure if it is the same incident but I remember reading about a similar (may even be the same) picture where they had parked a few 777's in a different place without telling the night shift. The night shift came in, started the stacker and burried them all!