About 12-14 and that's on the aircraft... if it's the first time you've flown for a while let the H sit powered up, but motors off for about 15 minutes to download the current GPS almanac, as well.
I use a consistent 10 count on both the aircraft and the transmitter. However, if my intent is to fly in Angle mode I’ll often take off with only 8 on each one. As Smart mode and BLOS is never used the above covers 100% of my flights.
In my neck of the woods I consistently get 16 or more satellites showing for the aircraft and typically get 18 to 20 satellites...occasionally 21. So for me, then, I would consider anything less than 15 satellites as a no-go (I have never got less than 15 satellites so I've never had a no-go because of a lack of satellites seen).
Am I lucky? Is it because I live in a part of the world that 'sees' more satellites? I dunno. All I know is that (for my TH) I never have any problems seeing satellites...My Phantom, on the other hand, is quite another kettle of fish.
Thanks to all of you who have responded to my question. It does seem that the ST 16 is sometimes slow to aquire satellites. I get a 8 - 9 - 10 -9 -10 -8 - 11 and so on. The bouncing around in the number of satellites just seems strange. by the time I've gone through one battery I'm at 15 - 18 range.
No real issues but trying to prevent trouble while in the air.