Originally Posted by gobluetwo

Was it below 10k feet? The power is only supposed to be on above 10k feet or when parked. Below 10k feet, power is off as indicated by a lack of green light on the outlet. I've had no issues charging my various Lenovos (3 different T420's and a T440) on the 737.

Or maybe it's because you have an ancient IBM Thinkpad