Entering commercial service recently in 2018 with Singapore Airlines, the Boeing 787-10 is the "big brother" of the family.
While the 787-8 was about proving the composite technology, and the 787-9 was about perfecting the balance of range and payload, the 787-10 is purely about economics. It was designed to be the most fuel-efficient twin-aisle aircraft per seat in the sky on medium-to-long-haul routes, competing directly against the Airbus A350-900 and replacing older jets like the Boeing 777-200ER and Airbus A330-300. More information below.