The Bombardier CRJ-900 is a stretched variant of the CRJ-700 and part of the CRJ family that defined North American regional aviation for two decades. The aircraft entered service with Mesa Airlines in 2003 and seats 76 to 90 passengers in typical configurations. The CRJ family has a distinctive narrow cabin compared to the Embraer E-Jets, with four-abreast seating and a lower ceiling. This has made the type less popular than the E175 on routes where passenger comfort matters, but the CRJ-900 has remained in heavy service with regional carriers thanks to favorable operating economics on shorter routes. Bombardier sold the CRJ program to Mitsubishi Heavy Industries in 2020, and production has since ended. In 2026 the aircraft is still operated by many regional affiliates in North America, though retirement is accelerating as newer types arrive.