@Suzk123, although I didn't have Air Expanders, I did interview Dr Tony Connell in WA (who was the first surgeon to trial them) for Reclaim Your Curves and this was his advice about flying with the expander:
RYC: Is it safe for women to fly with the expander in?
TC: This is one of the questions I looked at as part of the ASPIRE study into the device. Those patients that have flown with the device at altitudes above 1,000 meters did report a slight filling sensation upon ascent, which then normalised on descent. Based on those results I recommend that it is safe for patients to fly with the expanders implanted, but dosing of the AeroForm should be discontinued for 2 weeks before flying and resumed once the patient has returned home.
It's probably a good thing to check with your own surgeon as well, especially since the Airexpanders have now been on the market for a few years now and this advice may have been updated.
There are a few members in the Choosing Breast Reconstruction group who have had Air Expanders and who may have flown, so feel free to join the group and post there as well. Jane xx