Engine manufacturers begin preparations to meet Boeing proposal for new Advanced derivative of widebody

The competition to power Boeing's proposed 747 Advanced derivative is starting amid signs that using unchanged baseline 7E7 engines will not be possible, and that the General Electric/Pratt & Whitney Engine Alliance may enter the fray.

In addition, the relatively restricted market potential of the new derivative, added to the cost of developing a refanned version of an existing or planned powerplant, indicate a winner-takes-all competition. Boeing says "no decision has been made on how many suppliers" will be selected and says it is "still studying several configuration options. We are not ruling out refanning 7E7 engines for a better match." It adds it therefore does not "rule out a minor derivative" version of the GEnx or Trent 1000 7E7 engines now in development, or possible proposals from "P&W or the Engine Alliance".

Engine Alliance president Lloyd Thompson says: "We are supporting those studies and are ready, willing and able to propose the [GP7200] engine on whatever Boeing is ready to do." The Alliance, which was formed for Boeing's major stretch attempt on the 747 in the mid-1990s, then designated -500X/600X, says its original mission statement "is good as long as it is a four-engined aircraft with more than 450 seats. The proposed 747 variant meets these qualifications."

P&W says the technology developed for its PW-EXX 7E7 bid "continues to be spread across the product line and we continue to have ongoing discussions with Boeing about new aircraft programmes."

The main contenders are still believed to be GE and Rolls-Royce, both of which are studying refanned 7E7 engine variants to reduce fan diameter from 2.79-2.84m (110-112in) to around 2.56-2.64m. The reduction is required after analysis revealed continuing configuration issues with the outboard engine at the 7E7 fan diameter because of interference drag and potential aeroelastic effects.

Boeing plans to brief airlines on the new 747 derivative in Hong Kong later this month.



Source: Flight International