It seems that Gib is about to get much anticipated Heli tourism!
IS IT A BIRD? Gibraltar introduces helicopter sightseeing tours in 2019 with Norwegian firm Fonnafly - Olive Press News Spain
Apparently a big issue was the danger to rare migrating birds that transit the area (I'd be more concerned about any danger to the Heli!) but it seems to have been solved by having some sort of trained ornithologist/observer on board.
Single engine over water, even if a turbine? Well, plenty of existing operators have done this type of flying for many years and I'm sure the Gib startup will have the required flotation equipment for the pax/Heli.
Wishing them the very best of luck when they start in May and I might even treat myself and the wife to a whizz - any excuse to get in the air!!!