The 777X is unlikely to be delivered before 2023, Boeing says. 

 

The first 737 MAX 10 and 777X delivery dates "reflect a number of factors, including an updated assessment of global certification requirements informed by continued discussions with regulators and resulting in a management decision to make modifications to the aircraft’s design,” Boeing said.

 

The MAX 10 is set to be the biggest member of the family and aims to compete with the popular A321 from rival Airbus.