Paul Lewis/SEATTLE
Boeing is discussing a further increase in the 777-200IGW's maximum take-off weight (MTOW) as an interim step towards a new ultra-long-range derivative of the twinjet.
The US manufacturer is considering offering a 777-200IGW+ version for entry into commercial service from 1998 onwards, says Boeing product marketing regional director Ragnar Nordvik. The aircraft would provide airlines with extended maximum range of up 13,875km (7,500nm).
The study is understood to be in response to Air France's recent order for ten 777-200IGWs. The carrier has specified that it wants an aircraft with a higher MTOW of 294,000kg (Flight International, 27 November-3 December, P13).
Ragnar says that increasing the weight would entail making "minor changes" to the existing 777-200IGW, the first of which is to be delivered to British Airways in February. The aircraft now has a MTOW of 287,000kg and a maximum range of 13,200km.
Modifications would involve fitting the -200IGW+ with the same reinforced landing gear as that planned for the stretched -300 version, a thicker wing gauge and software changes to the flight- management computer to take into account the new operating weight.
The structural reinforcements would weigh 227kg, pushing the aircraft's operating empty weight to 143,373kg. No changes are planned to the -200IGW's 170,000 litre fuel capacity, but the higher MTOW margin would allow the aircraft to carry extra fuel with a full 305-passenger load.
Other performance changes would include a 290m-longer take-off field length, a lower initial cruise altitude of 34,000ft (10,350m), a lower engine-out altitude of 12,250ft and a 0.1% rise in fuel consumption per seat.
Airlines operating the 777 view the -200IGW+ as an evolutionary development towards the ultra- long-range -200X derivative. The aircraft under study would have an MTOW of 322,340kg and a maximum range of 16,000km.
Source: Flight International
