Bose QC3 headphone
£245 Tax Free from BHX, about £275 from Bose direct, and stupid money "Tax free" from USD$ & Euro (Dutch) based OOA Px'.
These are the noise cancelling ones, recently (sucessfully) tested with a hovering Chinook nearby. Cost a lot, but earn their keep and most parts are individually replaceable if a drama should occur.
Link:
BoseQC3