enstrompilot
Shouldn't that be (Alouettepilot?!!) How are you chap?
1000m is quite a long way; I don't think the noise will be an issue in reality and I don't think you could argue that their position would affect your approach either. You're a smart chap and I'm sure you'll sort it out; any objection must be based on the usual rules, which normally exclude any visual impact (unless in an area of outstanding natural beauty, etc.). However, noise and disturbance are considered to be valid objections, so
if you can prove disturbance, you may make some progress. Definitely worth engaging a professional.
Good luck mate
PS Good to hear you've got the biggest heli-pad in the UK so far ;-)