Boeing has rolled out the first 787-9 aircraft at its Everett, Washington production facility.
The company says it is preparing to fly the aircraft "later this summer".
The 787-9 is 6m longer than the 787-8. It can carry 40 more passengers than the 787-8 and can fly 300nm (555km) farther.
The second and third 787-9 aircraft are in final assembly. The first example will be delivered to launch customer Air New Zealand in the middle of 2014.
According to Flightglobal's Ascend Online database, Boeing has 367 firm orders for the 787-9.