Boeing delivered the aircraft in Seattle late Wednesday. United will initially put it to use on Houston-based routes on Sept. 20. On Oct. 26, United will inaugurate six-day-a-week 787-9 service between LAX and Melbourne, Australia, which at 7,927 miles would be the longest 787 route in the world.
For now, United's San Francisco-Chengdu flight, at 6,857 miles, is the longest 787-8 flight to operate non-stop in both directions, while the longest single direction 787-8 flights are Ethiopian Airlines' flights from Addis Ababa to Washington at 7,182 miles and to Toronto at 7,143 miles. The eastbound flights are non-stop but the westbound flights both stop in Rome.
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The 787-9 has a range of 8,550 miles, compared to 8,200 miles for the 787-8. The 787-9 fuselage is trenched by 20 feet.
United will operate the 787-9 with 252 seats, including 48 in business and 204 in economy. Of the economy seats, 88 are Economy Plus seats with added legroom and increased personal space. United operates the 787-8 with 219 seats, including 36 in Business and 183 in economy, which includes 70 in Economy Plus.
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The first 787-9 was delivered to Air New Zealand in June, while the second delivery was to ANA in July. In August, ANA became the first airline to put the 787-9 into revenue service.
United operates 11 Dreamliners and has orders for 54 more, including 26 more 787-9s.
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"The 787-9 builds on the Dreamliner's fuel efficiency and customer comfort while giving us even more flexibility and range," said Ron Baur, United's vice president of fleet, in a prepared statement. "Last year our customers gave the 787 the highest customer satisfaction scores of any aircraft in our fleet, and we know they'll enjoy what the 787-9 has to offer."