I got a little confused there with the question. Of course the VFR limits below 3000 feet for a helicopter includes a vis of 1500m. My point was that my personal limit is to look out the window and only fly as far as I can see. That could be more or less than 1500m, but how do you measure that?
Ps Now what about that height AGL that you're prepared to go down to remain VFR?
Don't know, I suppose it depends on the terrain (probably 200 ft.). I have landed on several occasions when it got too bad. Nice of you to ask.
