Strangely enough I went to buy a pair or sunglasses only today in readiness to doing flight training in the US.
I hadn't read this thread until now, but my criteria were:
- The arms of the frames should be as thin as possible so they would pass under my headset
- The arms of the frames would not stick out from my face too much so (again) would pass under my headset.
- Not polarised.
- Offer 100% UV protection
I went to an optician after going to a sunglasses-hut kind of place and being very unimpressed by their technical knowledge of what they were selling.
The opticians were great, and got a (non-prescription, ie. no correction) pair of Silhouette 8592 /55 6086. These have titanium nose bridge, and arms so you can bend them out completely and they spring back into shape again. They are frameless. Got them for £80 from a high street 'express' optician (who had a 50% offer on a range).
I've not tried them in the air yet, but I have tried them under my headset (DC 10-13.4) and the ultra-thin arms (about 500 micron) pass under perfectly.
Tiggermoth