Parachuting from helos? Lot's but 20 years ago. Simple process for permissions which was identical to fixed wing operations away from a drop zone - displays etc. 90% of displays/demos were fixed wing once we'd quoted helo costs but paperwork was identical. Os map ref and copy required. Assessment of ground hazards and so on. Liason with local ATC watch.
Very busy doing it for a while: some may remember the Barrattts A109 dumping it's contents with monotonous regularity over housing developments
Much more muddy than even the worst UK DZ. The semi-glam divorcees Barratt's employed at each site showhome/office were most welcoming
Rob