I cannot see how such an advisory board would have any legal right to make any demands whatsoever pertaining to your flying operations.
If you believe your operation could be potentially jeopardised by the complainants then this sounds like a job for a capable lawyer and a
PR firm.
You've mentioned you are on as island - have you looked at the viability of a pontoon or barge in order to relocate the take-offs and landings to a less populated area?
Mafia Tactics:
1) Arrange for about 20 or so of the complainants to be kidnapped and held in a warehouse/facility with enough space for landing 2-3 helicopters. Pay a couple of the local police (or a security firm) to play-out a stand-off with the 'kidnappers' at the gates of the facility. At some point bring your entire fleet to swoop-in with some black-clothed 'SWAT style' security personnel and load the complainants aboard your aircraft and whisk them away to safety. When they eventually pass by your offices to express their gratitude, mention the fact that you'd appreciate it if they would back-off with their complaints.
2) Hire someone to fly around the island at the lowest legal height in a fully-laden Huey for several hours a day for a couple of weeks. When the complainants are at the point of killing themselves .. you and your crew offer to rid the complainants of the blade-slapping Huey through your 'higher' negotiating powers as fellow blitterblat drivers. Once the Huey is gone and the media have done a good job of crediting your involvement in sending it away .. have 20,000 stickers made-up with the name of your company and a sentence stating that you rid the town of the Huey so that all your complainants will ever hear about you is the fact that you dispatched a greater evil! If you're really clever (and in order to save cost) you'll manage to pull this off by getting an entire flight of the National Guard to run their Huey training ops out of your field for a time.
Many more suggestions but .. its getting late!
