I think the issue is not with the camera, per se, but rather, with having a loose "thing" as one approaches a helicopter with blades turning. If a person has not been near one, the wind is unbelievable. On an unstable surface, it would be easy to fall, and to lose the camera, which could end up in the air, and in an engine, disabling the copter.
When I've been involved in air operations, they are careful to orient us to not have loose "things" on our bodies.
On the other hand, it could have to do with stopping the fun filming, and getting into gear and onto the helicoptor. At a thousand dollars a minute or more, 20 seconds of filming is pretty expensive.
