Originally Posted by
chistery
As iPads require more power than a standard USB port, it may not work. I think they need 10W instead of every other device needing 5W.
I doubt that the onboard USB will deliver 10W. It is still possible to charge the iPad using USB, but only when the device is switched off. When off it will trickle charge from a standard USB port, but take 10 hours or more to charge fully!
If there are standard plugs in the floor then your best bet is to use the Apple mains charger or mains-charge it fully in the lounge before the flight.