I was getting hi-temp gripes on one of mine over the weekend – it was only 103F outside, and I had the sealed metal enclosure containing the Pi3, SDR, and POE board covered with a cardboard sun shade – the Pi3 was only hitting 70C! When the sun went down, it cooled off to under 50C.
Not sure what good a heat sink on the CPU would have done – I think CPU utilization was under 30%. A fan inside the enclosure would have turned it from a normal oven into a convection one, not sure what good that would have done.
If I go with this setup long term, I’ll probably mount the Pi3 board to the enclosure using a relatively thick sil-pad, which will conform to the bottom of the board and provide a reasonably low thermal resistance to the enclosure. (Bergquist Gap Pad VO Soft, great stuff but not cheap)
Device temps start hitting 90C and I worry. 70C is warm, but survivable. SanDisk on their website says their microSD and micrSDHC cards “are capable of surviving operating temperatures from -13ºF to 185ºF (-25ºC to 85 ºC).” I’d note that “survive” is not the same as “happy and long lived.”
Question: what’s FlightAware’s threshold for hi temp?