|The Boeing 737NG is a conventional, medium-size airliner with podded engines and sweptback wing and tail surfaces. All NG versions have greater range and speed envelopes that previous older generation 737s, and operate with lower noise and emissions. The aircraft is fitted with newer high-lift systems, larger tail surfaces, increased wing area, increased tankage while still being able to use the same runways, taxiways, ramps and gates as preceding variants. All versions are powered by a new variant of the CFM56 turbofan engine and is derated from nominal thrust to suit smaller versions of the family. Ground noise is reduced by approximately 12 dB due to the installment of a new diffuser duct and cooling vent silencer on the APU.
All flight controls on the 737NG are conventional and hydraulically powered by two independant hydraulic systems with manual reversion for ailerons and elevator. The wings are fitted with three outboard-powered overwing spoiler panels which assist the ailerons in lateral control and also act as airbrakes. Furthermore, the aircraft has leading-edge Krueger flaps inboard and four sections of slats outboard of the engines, two airbrake/lift dumper panels on each wing, inboard and outboard of the engines, and continuous-span, double-slotted trailing-edge flaps inboard and outboard of the engines.
The 737NG has an aluminium alloy dual-path fail-safe two-spar wing structure with a corrosion-resistant 7055-T77 upper skin. The ailerons, elevators and rudder are constructed of graphite composites. The fuselage structure is of the fail-safe construction. The rears of the engine nacelles are of graphite/Kevlar/glass fibre.
The aircraft is operated by a flight crew of two sitting side by side on the flight deck. There is one plug-type door at each corner of the cabin, with passenger doors on the port side and service doors on the starboard side. An optional airstair for the forward cabin is optional and utilized by several airlines. Overwing emergency exits are provided on both sides of the fuselage. The aircraft has a lightweight interior with a movable class divider, overnight seating-pitch flexibility and modular passenger service units that include fold-down video screens in the underside of the baggage bin. All versions have two underfloor baggage hold, both forward and aft of the wing.
The Boeing 737-900 has alternative cabin layouts capable of accomodating 177 to 189 passengers. Typical arrangements offer 12 first class seats in a four-abreast seating, and 165 tourist class seats in a six-abreast seating in mixed class. A 189 seat configuration is achieved in an all-tourist class configuration.
The NG series is fitted with a Honeywell 131-9(B) APU with air start capability to maximum certified altitude and 90 kVA electrical load capability to 37,000 feet. Furthermore, a three-wheel air cycle environmental control system with optional ozone converter and digital cabin pressure controls is part of the package.
Standard installation include satellite navigation and an optional satcom and dual FMS (single standard) integrated with the GPS.
The Boeing 737-900 is powered by either two CFM International CFM56-7B26 turbofans, each rated at 117 kN (26,300 lb st) standard, or two CFM56-7B27s, each rated at 121,4 kN (27,300 lb st) in the high gross weight version.