Shoehorned into economy class seats on an Ethiopian Airlines “Dreamliner” on our way back from Heathrow to Addis I discovered that you should only put one, not two, flimsy plastic cups into the cup holder on the back of the seat in front. Chris was sleeping peacefully with an empty cup in front of her and trying not to wake her I popped a fresh plastic cup of water into the empty one ready for when she awoke.