Putting the X in Triple Seven

Putting the X in Triple Seven:
The B777 family is Boeing’s second most successful widebody after the venerable B747 and fast on its way to assuming pole position. Having been in service for just under 18 years and already updated once, the Seattle-based manufacturer is now looking to renew the twin-engined airliner once more in an attempt to fend off the threat caused by Airbus’ new A350 and defend its own market.
The resulting Boeing 777X programme is no hidden project, with CEO Jim McNerney admitting that the company was actively pursuing a stretched and improved version of the current B777 family as early as 2010. Currently two main derivatives are being studied; the -8X would be a stretch of the current -200/ER/LR fuselage, and the -9X would be based a lengthened -300/ER fuselage. These would compete with the larger variants of the Airbus A350 currently being assembled; namely the -900 and -1000. With the new Airbus widebody touted as being 15-20% more efficient than the current B777 family, Boeing has recognised the need to improve its own products to meet these claims, as a result, the Boeing 777X will receive new engines and new composite wings.
The new composite wing will be Boeing’s largest ever, with a wingspan of over 71 metres it will provide significant weight reductions and better overall aerodynamic properties. To facilitate the larger wingspan without pushing the aircraft into a larger airport category, Boeing is re-visiting an old concept; folding wings. The idea stems from a design first studied for the original Boeing 777, when the manufacturer went as far as building an actual test rig for the mechanism. Unlike the original folding wing concept, Boeing is reportedly looking at a simpler and lighter mechanism that only folds the wingtips, which would be devoid of any control surfaces.

This is the original B777 folding wing test rig. Currently hidden away in Boeing’s Everett facility, it may already be back in use in proving tests for the upcoming project

The contest between engine manufacturers for the B777X contract is also rapidly becoming a fierce battle. Initially all three big players; General Electric, Pratt and Whitney and Rolls Royce, expressed an interest in the programme. Since then Pratt and Whitney have reportedly bowed out of the competition, leave General Electric and its GE9X to contend with Rolls Royce’s RB3025. Both engines are claiming to improve fuel burn by 10% and are believed to be more developed versions of the GEnx and Trent 1000 respectively. Unlike the current trend of larger fan diameters, the engines manufacturers have hinted that the powerplants will be smaller than the GE90-115B power the B777-300ER, achieved by scaling down the engine core. This agrees with the overall reduction in thrust available as both engines will fall into the 95,000 to 100,000lbs mark, significantly less than the current 115,000lbs.

With the B777-8X being significantly larger than the current B777-200ER, the prospects for the B787-10 are all but set in stone

Even if the Boeing 777X programme is launched this year, it is not expected to enter service until 2018 at the earliest, one year behind the brand new A350-1000. It is anticipated that a 2013 launch is likely, together with a B787-10 launch. As a result, the current Boeing 777-200ER will cease to be competitive, cannibalised by it’s own sibling, the Boeing 747-8, itself a relative newcomer, will also have little future. This projection provides an insight that in less than a decade, all Boeing commercial aircraft will be single deck twin-engined airliners.