Boeing is studying development of a larger stretched variant of the new-generation 737 twinjet, to compete more effectively in the 180-200-seat class against the Airbus A321.
Boeing has refused to comment officially on the proposed 737-900X growth derivative, which was only revealed as a study to suppliers at the end of April.
According to company sources, the stretch would be developed from the existing -800, with a similar fuselage extension to the 2.38m difference in length between the 31.2m-long 737-600 and 33.6m-long -700. The -900X would incorporate two additional plugs, one each side of the wing, in addition to the 1.17m and 1.63m extensions already incorporated into the -800's stretched fuselage.
The longer fuselage would allow for the addition of three more rows of seats, adding 18 more passengers in a six-abreast configuration to that of the -800, which seats 162 passengers in two-classes or 189 in a high density layout. The -800 cannot match the larger A321, which can accommodate185 passengers in a two-class configuration or 220 in a high density layout, similar to the 757-200. Several airlines are understood to be looking at the 737-900X, including Aer Lingus and China Airlines.
Other changes to the -900X are likely to include a strengthened landing gear to cope with the longer aircraft's increased take-off weight and landing speed. The aircraft will probably be otherwise identical to the -800, and is expected to retain its tail skid and expanded environmental-control system.
CFM International, which produces the CFM56-7 engine for the 737 family, says: "We are aware of the programme, but we have not yet been formally approached to study what it will take to power it." It is thought that the aircraft will require up to 127kN (28,000lb)-thrust, which would require a simple "throttle-push" development of the -800's CFM56-7B26, rated at 117kN.
Source: Flight International
