Boeing 787 Dreamliner - Mark Wagner [66]
For the first time in any wide-body engine development program, Rolls-Royce felt the need to use a dedicated flying test bed for the Trent 1000. The ex–Air Atlanta Icelandic 747-200 was converted for the role by L-3 in Waco, Texas, and commanded during its initial test runs by Rolls-Royce Chief Test Pilot Phill O’Dell. The aircraft is pictured taking off at Boeing Field with the test engine at idle. Mark Wagner
Trent 1000 Chief Engineer Andy Geer described the ANA decision as a “great vote of confidence” that gave Rolls-Royce a good “leg up” in the battle to power the initial 7E7. The engine was to be built as a single bill of material across all three versions despite a broad thrust range covering certification at about 70,000 pounds of thrust for the 7E7-9, and derates to 63,000 and 64,000 pounds of thrust on the initial 7E7-3 and 7E7-8 variants, respectively.
Bolstered by the addition of a new commitment from Air New Zealand, which became only the second 7E7 customer to select an engine, Rolls revealed further details about its development plan. By now defined with a 10:1 bypass ratio and 50:1 overall compression ratio, the final design of the Trent 1000 was due to be frozen by February 2005, with first engine to test scheduled for mid-February 2006. The basic test, development, and certification effort was to involve seven sea-level engines and a flight test engine, requiring Rolls to operate its own dedicated flying test bed for the first time since the 1970s.
In late December 2004, L-3 Communications Integrated Systems was given the job of modifying and operating a 747-200 selected for the purpose. An RB211-524C2-powered aircraft acquired from Air Atlanta Icelandic was reregistered N787RR and flown to L-3’s modification site in Waco, Texas. The 747 was a far cry from the ex-RAF Vickers VC10 last used to test the original RB211.
Just as Rolls was securing its deal with L-3, GE signed an agreement the same month with Airbus to use the GEnx as lead engine on the European company’s newly announced A350, at this stage an advanced A330 derivative aimed at countering the 7E7 (see chapter 10). The Airbus deal slotted perfectly into GE’s strategy of developing the GEnx into its twenty-first-century CF6 successor, a policy that would be further reinforced with the engine’s sole-source selection the following April for the newly announced 747-8.
The GEnx development by now was accelerating, with teaming arrangements and the design firming up. Japan’s Ishikawajima and Mitsubishi, Italy’s Avio and Sweden’s Volvo Aero, and Belgium’s Techspace Aero all became partners, with a combined share of 36 percent of the program.
Fuel is injected into the GEnx engine’s TAPS combustor and thoroughly mixed with the swirling airstream to create a leaner air/fuel mixture. As this burns at a lower temperature in this combustor, the formation of nitrous oxides and other greenhouse gases is reduced. GE
Test Trent engine 10009, the eighth full engine to enter evaluation, soars overhead on the Rolls-Royce 747 flying test bed. Rolls said the “relatively unpredictable conditions of a flying test bed” made the converted airliner a valuable asset during the certification program. Mark Wagner
In something of a landmark moment for big engine design, GE also announced that the GEnx would feature a composite fan case to save weight and improve strength and containment performance. Having been the first to introduce large-scale composites in the fan of the GE90, GE was better prepared than any to replace the conventional metallic fan case with the newer material, which it said would save close to 350 pounds per engine.
Suspended on its test stand in the rural wilds of Ohio, the second GEnx-1B, Engine 956-002, gets ready to undergo