Recently I travelled to Australia via Cathay Pacific airlines. This was a full 36 hour trip. The seating was extremely uncomfortable. I had one of those inflatable neck pillows and made a startling discovery. In desperation I inflated the pillow VERY lightly . . . a good 2 or three breath's worth. Then I turned it around with the opening to the back and placed it on the seat and used it as a cushion.
It made ALL the difference in my comfort level. I will NEVER be without one of these pillows again. They pack easily into my purse and can be deflated and repacked easily. I hope this hint is useful.