Boeing has obtained its first firm order for its 737 MAX as part of a $US19 billion deal.
Southwest Airlines has commissioned 208 new Boeing planes, including 150 MAX aircraft. It is Boeing's largest order ever.
Southwest is first in line to take delivery of the upcoming revamp of the 737, which will feature a new energy-efficient engine.
Boeing chief executive, Jim Albaugh says the company has commitments and firm orders for 948 new 737 MAX planes.