Boeing Commercial Airplanes reported it completed the first 787-9 Dreamliner, the second variant if its high-profile passenger jet family. It unveiled the new jet at the Everett, Wash., factory, and its workers will continue to outfit it in preparation to fly later this summer.

Three of the new jets will be delivered to Air New Zealand in 2014.

The “Dreamliner” is a wide-body twin-engine aircraft with long range and carrying capacity for 210 to 330 passengers. Boeing says it is its most fuel-efficient commercial jet, with a structure based on a large volume of composite materials helping to reduce fuel consumption by up to 20% versus similar-size jets. A more advanced aerodynamic design than previous jets, more-electric systems, and modern engines add to the 787’s appeal to airlines.

After many delays in design and development, the first Dreamliner, a Boeing 787-8, was delivered to All-Nippon Airways in 2011. Numerous more of that version of the jets have been supplied in the interim.

The 787-9 has a longer (“stretched”) fuselage, and will seat 250–290 passengers in three classes (40 more than the current Dreamliners.) It will have a flight range of 8,000 to 8,500 nautical miles (9,200 to 9,700 miles.) It differs from the 787-8 in that it has a higher fuel capacity and a higher maximum take-off weight, but it has the same wingspan as the 787-8.

Also, Boeing noted the 787-9 will continue to achieve “exceptional environmental performance — 20 percent less fuel use and 20 percent fewer emissions than similarly sized airplanes,” as the current 787-8 jets.