In reply to The Lemming:
Have tried various types over the years when doing regular long haul business flights.
Only ones that totally shut out airplane noise are ones that completely cover the ear, not just rest on top.
Of these the Bose were the best which I now use.
Tried in ear ones which work well if pushed right into the ear but never found any that were comfortable and couldn't really find a way of easily sorting out earwax / blockage or the earpiece.
Noise cancelling ones exert an air pressure onto your ear and its noticeable. Since they are pumping out the inverse of the background noise continuously as well as the signal you want to listen to.
Have tried ordinary headphones and a battery powered amplifier but not that successful.
However unless you are taking the dog for a trip along a city road or airport the background noise may well be a lot less than in a plane which is surprisingly loud. So you may well find a comfortable pair of Bluetooth headphones best.