Boeing chief financial officer Greg Smith says the 777-9X is still on track to begin flight tests later in 2019 despite the need for some re-testing work on the GE9X engines powering the aircraft.

Boeing staff have had a first look at the new 777-9X at an internal event at the company's Everett facility just outside Seattle in Washington State.

Boeing has won its first 777-X orders for about two years and secured a new airline customer for the type after British Airways signed for up to 42 aircraft.