Hmmm well there’s nothing scientific about this but I just flew 40 Hrs mostly in a record hot mid-west with iPads on the passenger seat (Although, in the Cessna, never directly in sunlight because of the shade effect of the high wing) without any issues of shutting down. The actual issue was insufficient battery life for 7 Hr flying. I ran the primary iPad (generation 3, faster) down to 30% before switching to the standby iPad 2 to use 70% of it’s power. I never needed the power in the reserve iPad mini and used it as an AF/D display. (BTW, all these hold perfect satellite lock. I would not dream of using an external GPS with all the battery charging reliability issues that would bring).
Here’s a sneak preview of the power of Foreflight on iPad: (Trip report to follow, eventually)
I do have a battery pack, but this only just keeps up with the power use due to the charge rate and does make the iPad feel hotter although again I’ve never had a shutdown.
So I’d say overheating can be avoided (in a high wing, anyway) and that a bigger hazard is limited duration running Foreflight with the screen turned up on 4 Hr legs in a plane without a cigar lighter. Not to mention forgetting to fully recharge the night before….
Aveling wrote:
I do have a battery pack, but this only just keeps up with the power use due to the charge rate
My iPad Mini is the same with on board power supplied by an accessory plug… But it rarely goes below say 75% on any long trip I might make. My backup iPhone stays at 100%.
iPad overheating is not a problem with a little ventilation air blowing on it, even under a bubble canopy, as I think I’ve posted here before that is a problem long since solved for my use. My biggest issue is that the iPad mini screen is barely bright enough – the iPhone is brighter. I usually keep both running down the same Foreflight magenta line.
I’ve seen all sorts shut down, not just iPads. Our standard fit is three Lenovo tablets and two iPad Minis. All of these have overheated in flight, normally in the Middle East with cockpit temps of 40+ Celsius. The Lenovo batteries are particularly bad at retaining charge but plug-in the charger and it will overheat more quickly. I’ve also seen Garmin GLOs, SkyEcho and PAW shut down due to excessive temps. Of course, one can mitigate the risk by keeping devices in the shade or utilising the extra crew member to wave the errant tablet in front of the aircon vent. 
My iPad Mini is the same with on board power supplied by an accessory plug… But it rarely goes below say 75% on any long trip I might make. My backup iPhone stays at 100%.
iPad overheating is not a problem with a little ventilation air blowing on it, even under a bubble canopy, as I think I’ve posted here before that is a problem long since solved for my use. My biggest issue is that the iPad mini screen is barely bright enough – the iPhone is brighter. I usually keep both running down the same Foreflight magenta line.
Yes same with me! 
My iPad Mini, yoke mounted, has overheated on three of the last four flights (Arrow IV). I now use a ventilated holder. In each case the sun was shining over my left shoulder late in the afternoon so directly onto the screen. Hopefully the problem is now resolved.
Peter_Mundy wrote:
My iPad Mini, yoke mounted, has overheated on three of the last four flights (Arrow IV). I now use a ventilated holder. In each case the sun was shining over my left shoulder late in the afternoon so directly onto the screen. Hopefully the problem is now resolved.
I also just received a new ventilated holder for my ipad mini. Last time I did a cross-country beg of May, it was overheating with an AOT of 25C and pure blue sky!
That’s the one I have.
Interesting comments about overheating. I’ve only had one overheating event, and that was when I put an old iPad2 on the dash for 15 minutes or so where it sat in direct sunlight. The iPad Mini2 (WiFi only) I use now has – so far – never overheated. It lives on a non-ventilated yoke mount in Cessnas, mostly C210. I did, however, buy a mount that leaves most of the back exposed, so doesn’t enclose the tablet completely as some mounts do. What may also make a difference is that I don’t have supplemental O2 and therefore rarely venture into the thin (and this less heat dissipating) air above 10 or 12k ft.
My blackouts were all at <3000ft AMSL :(
Peter_Mundy wrote:
My blackouts were all at <3000ft AMSL :(
Interesting. Most of my flying is between 8 and 11k.
