FARNBOROUGH -- The Engine Alliance, a -Pratt & Whitney joint venture, plans later this year to define a new set of performance upgrade packages to the ’s GP7200 engine as continues to evaluate future propulsion options ranging from incremental improvements to re-engining.
The packages cover a variety of options ranging from relatively minor, near-term changes that could be fielded by 2017, to more substantial revamps that would involve wholesale changes to the flowpath as well as an increased diameter fan. “The first package we could certify by analysis, and launch and introduce by the second half of 2017,” says EA president Dean Athans. Initial upgrades could yield specific fuel consumption improvements in the 0.5% to 1% range, while more comprehensive packages are aimed at between 2% and 5%.
These latter phases would potentially involve the replacement of the blades and vanes in the flowpath with a new generation of three-dimensional aerodynamically designed shapes, an additional low pressure (LP) turbine stage and a larger fan. However Athans concedes that the cost and timing of the larger-scale upgrades could be “cost prohibitive” in the absence of a compelling business case, while nearer-term improvements form part of the on-going efforts to maintain competitiveness with
The newest enhancement package, which is focused largely on improving the durability of the high pressure (HP) turbine, is aimed at improving time-on-wing by up to 50%. Upgrades include optimized clearances and better blade, nozzle and shroud cooling in the first and second stages of the turbine. The package will also help slow down performance retention, particularly in the tough operating environments for leading GP7200 operator Emirates Airlines.
“We had an army of engineers working on it in 2013 and we froze the design in October. It will be introduced this summer,” says Athans. The Engine Alliance has also negotiated with German engine maker and partner MTU to run a 3,500 cycle endurance test of the engine with the new core upgrades in place. The test facility will be specially modified to simulate the environment of Dubai by injecting heated air and dust imported from the United Arab Emirates into the inlet. Testing is scheduled to run through the end of the year. A variety of other external and internal enhancements are also planned, including a software upgrade for improved clearance control which will be introduced in mid-2015.
The GP7200 has also been certified at two new thrust ratings. The first, the GP7272, allows the GP7200 engine to operate at 72,000 lb. thrust. The second, GP7272E, allows the engine to operate with the same thrust at higher ambient temperatures.