The "CRJ900" is a stretched 76–90 seat version of the CRJ700. The first CRJ900 (C-FRJX) was modified from the prototype CRJ700 by adding longer fuselage plugs fore and aft of the wings. It was later converted into the prototype CRJ1000 by replacing the fuselage plugs with longer plugs. The CRJ900 also features strakes located at the rear of the plane. The CRJ900 competes with the Embraer 175, and is more efficient per seat-mile, according to Bombardier. Mesa Air Group was the launch customer for the CRJ900 painted in America West livery. The FAA Type Certificate designation of the CRJ900 is the "CL-600-2D24". The wing is wider with added leading edge slats, the tail is redesigned with more span and anhedral. The cabin floor has been lowered 2 inches which gains outward visibility from the windows in the cabin as the windows become closer to eye level height. The cabin has a recirculation fan which aids in cooling and heating. The environmental packs have a target temperature instead of a hot-cold knob. The APU is a Honeywell RE220 unit, which supplies much more air to the AC packs and has higher limits for starting and altitude usage. The aircraft features two GE CF34-8C5 engines, thrust with APR. The engines are controlled by FADEC digital engine control instead of control cables and a fuel control unit. In typical service, the CRJ900 can cruise 8–10,000 ft higher with a slightly higher fuel burn and an average true airspeed of 450–500 knots, a significant improvement over its predecessor. Its maximum ground takeoff weight is 84,500 pounds. In 2018, the CRJ900's list price was $48 million while its market value was $24M; reportedly, most customers are paying around $20–22M and the American Airlines order for 15 was at below $20M. A 2012 aircraft was worth less than $14M and it was to fall by 30% in 2021. The CRJ700 "Series 705" is based on the CRJ900, featuring a business class cabin and a reduced maximum seating capacity to allow operation with regional airlines. The Series 705 seats 75 passengers. Some regional airlines have scope clauses with their major airlines that limit the maximum passenger capacity of aircraft they operate. The Air Canada Pilots Association negotiated a scope agreement with Air Canada limiting the maximum seating capacity of any jet aircraft at Air Canada Express to 75 seats.