Boeing officially launched the 737-900ER following the completion of a sales agreement for up to 60 airplanes to Indonesias first low-cost carrier, Lion Air. The new 737-900ER, formerly the 737-900X, becomes the newest member of the Next-Generation 737 family. The 737-900ER features aerodynamic and structural design changes, which allows the derivative to accommodate higher takeoff weights, carry 26 more passengers and fly farther than the 737-900.