This wind-up occurred sometime in 1993 when the Wessex was used for multi-engine helo training on 2 Sqn at Shawbury.
One of the advanced sorties involved flying the Wessex at high AUW to experience the handling characteristics. Unfortunately, one of the less capable students overtorqued one at Chetwynd and it had to be underslung back to Shawbury by Chinook. The procedure stated that somebody had to board the underslung aircraft to apply the brakes when it was placed on the ground.
A particularly gullible student was selected to be the brakeman and told that he had to be on board for the whole trip. In case the Chinook had an emergency and had to dump the load the brakeman was told to collect a parachute from stores so he could bail out. Having collected his parachute the student then waited at the edge of the main dispersal at Shawbury for the Chinook to pick him up en-route Chetwynd. The Chinook duly arrived and our hero waddled towards it wearing his 'chute. Somebody then ran out to tell him about the wind-up and indicated the rather large audience watching from every available window facing the dispersal. A very red faced student then faced the longest short walk of his life.
Ironically, he is now a Chinook pilot himself. I'm sure he remembers the incident.