I am experiencing the same problem. The battery drains too fast even when I am on an airplane mode with wifi and Bluetooth off (just for the sake of slowing down the drainage). Not only that but the charger that the Ipad came with doesn’t charge it and instead I need to use the charger of the Mac. After calling customer care I restarted and rebooted the device, the problem persisted. I am now using another iPad Air 4th generation (as the first one) and to my surprise - the second device is behaving the same way as the first one. Could that be a general problem with all new IPad devices?