The BBC News helo pilot had the right idea as he landed away up in a clearing on one of the hills before the event started, thus was free to take off shortly before the Lancaster arrived without spoiling the event through noise.
The Sky News helo pilot had already been told to make himself scarce for 10 minutes when the service started at 10am as he was making a fair bit of noise at that time (from my position on the slopes of Abbey Banks the helo was drowning out what seemed to be a band at the time). Bad form.