http://www.bbc.co.uk/news/magazine-23002635 But the worst thing about air travel (I then determined) was what happens in row 21, when the seat belt signs are switched off and passengers are free to move around. Immediately, zonk! Back comes the seat as the person in front assumes relax mode as a default position. So, faced with the anonymous unpleasantness of the passenger in front of me, I made a public vow. Never again - I promised listeners - would I press that tempting shiny button on the right hand side of the armrest.