Hi duguayjacques
I'm not with Laminar Research, just a fellow simmer in the UK, but a couple of basic questions:-
1. Presumably the helicopter models you purchased are written for X-Plane 11?
2. Presumably also, they are written for the correct operating system i.e. Windows or MAC?
3. Are they in the C:\X-Plane 11\Aircraft\Extra Aircraft folder?
Sorry for the basic questions, but when diagnosing, you should always start at the beginning :-)
Regards