Airport security's been stepped up further across the US.
Authorities in Washington say they won't allow electronic devices onto planes to America, unless they're fully working.
It's because of concerns that the casings of mobiles or tablets could be used to hide bombs.
The Department of Transport said it doesn't envisage any need for changes to security procedures here.
Sky's US correspondent, Dominic Waghorn, says it's likely to catch out passengers travelling from Europe.
