Boeing Co. (BA) is poised to win an order for 100 737 narrow-body aircraft from General Electric Co. (GE)'s jet-leasing unit, a boost in the U.S. company's competition with Airbus SAS, two people with knowledge of the transaction said.

GE Capital Aviation Services' purchase includes 75 upgraded 737 MAX planes, said the people, who asked not to be identified because they aren't authorized to discuss the deal. The order comes as the Farnborough air show, the aerospace industry's highest-profile trade event of the year, begins today near London.

Boeing is seeking more MAX buyers among aircraft lessors as it develops the fuel-efficient replacement for its top-selling 737, a rival to Airbus's A320neo. Leasing companies place planes with multiple airlines, which would broaden the base for the MAX before its 2017 commercial debut.

Narrow-body planes form the bulk of the global airline fleet, and Airbus got an eight-month head start on the A320neo by unveiling it in December 2010. That set up a rout of Boeing at the Paris air show in June 2011 as the A320neo amassed hundreds of firm purchases and commitments, and it wasn't until the following month that Boeing said it would offer the MAX.

Gecas's order would have a list value of US$9.25 billion, based on Boeing's retail prices for the 737-800, the most-popular version of the existing plane, and the equivalent version of the MAX.

Eric Jones, a GECAS spokesman, said the company doesn't comment on speculation about orders, and Marc Birtel, a Boeing spokesman, declined to comment.

Boeing has received 451 firm orders and hundreds more commitments for the 737 MAX, according to airlines' announcements and the company's website tally through June.

The MAX will be powered exclusively by new engines from CFM International, a joint venture between Fairfield, Connecticut-based GE and Paris-based Safran SA.