A glimpse of new Heathrow Airport Terminal 2
When Heathrow's Terminal 5 opened six years ago, it turned into a national embarrassment - there was chaos, including lost luggage and delays.
Heathrow Airport bosses say they have learned lessons and will try to avoid the same problems when Terminal 2 opens in June.
The airport is using volunteer passengers to test the terminal ahead of the big day. BBC London transport correspondent Tom Edwards spoke to volunteers and to John Holland-Kaye from Heathrow Airport.