Boeing's 787 test aircraft ZA004 will return to flying on 20 May with the first Rolls-Royce Trent 1000 'Package B' engine hung under its right wing, marking the beginning of tests on the updated powerplant meant to deliver specific fuel consumption (SFC) rates within 1% of the engine-maker's initially targeted specification.
The fourth 787 test aircraft had been down for maintenance since 27 April for installation of the engine and its extensive instrumentation. The left-hand engine is expected to be installed on ZA004 later this month, say programme sources.
The Package B engine includes a revised six-stage low pressure turbine (LPT) design, high-aspect-ratio blades, relocation of the intermediate-pressure (IP) compressor bleed offtake ports and a fan outlet guide vanes with improved aerodynamics.
Additionally, it is believed that the Package B engine also incorporates undisclosed hardware changes that were prompted following the August 2010 uncontained failure of a 'Package A' model Trent 1000 on the Rolls-Royce test stand in Derby, UK.
The test fleet, which Boeing said in April had completed 95% of certification requirements, had been flying with the Package A engine since the 787's first flight in December 2009.
Boeing and Rolls-Royce have not disclosed whether or not first 787 deliveries in the third quarter to All Nippon Airways will include the Pacakge A or B engines, though initial planning prior to the most recent programme delays indicated the first five or six Rolls-Royce 787s to be delivered would feature the A model engine.
Rolls-Royce received extended twin-engine operations (ETOPS) certification on the Package A engine on 9 May, clearing the way for engine-airframe ETOPS certification to be undertaken.
Boeing offers also offers a choice of General Electric GEnx-1B engines on the 787.