You need to turn off your phone or enable the Airplane mode on a plane, however, is it the same for wireless Bluetooth earphones? The short answer is yes.
According to the Federal Aviation Administration, “You can… continue to use short-range Bluetooth accessories”. Since AirPods count as short-range Bluetooth devices, you’re free to use them on planes. All you need to do is to turn on the Airplane mode and the Bluetooth at the same time. In addition, in the consideration of your safety, you should remove your earphones when the plane takes off and lands, as the ANC may prevent you from hearing any important announcements during that time.

In case that some airlines may still support in-seat entertainment systems, you have to either use a pair of wired headphones or purchase an extra Bluetooth adapter or transmitter, such as Twelve South Airfly. Just plug it into the headphone jack of your seat once you’re onboard and then connect it with your AirPods Pro or other Bluetooth headphones. It is small and portable, so you won’t feel inconvenient with it at all during long journey in plane.