l was looking on the website and noticed that American Airlines is now using the 767 for there once daily flight from raleigh durham to London Heathrow.l have been on this flight a lot to gatwik and it has always been the 777-200ER.l checked and it is only for the newt few weeks.

The only thing that comes to mind is maintenance.It is the same plane that goes to and from london each day aal173/174

l would assume the plane is just down for scheduled maintenance. after looking it up on flight aware, it departs and arrives on a regular schedule

Maintenance could be the reason, but more likely they decided to put the 777 on a route that has been very heavily booked for the next few weeks. The 777 holds about 300 passengers compared to the 200 passengers on the 767.