Boeing's oft-delayed 787 schedule may again find itself in jeopardy as the airframer and engine-maker Rolls-Royce investigate the failure of a Trent 1000 engine intended to power an early -8 delivery to launch customer All Nippon Airways.

R-R confirms that one of its "Package A" Trent 1000 engines suffered a failure during a sea-level test at the company's Derby, UK facility. The engine-maker and Boeing are working closely to determine the cause and R-R says: "We are now investigating in detail and have made good progress in understanding the issue. We do not anticipate any impact on the programme."

However, Boeing strikes a more cautious tone, with its year-end delivery target to ANA already at risk of slipping into 2011 as a result of sluggish flight-test instrumentation change-out and horizontal stabiliser inspections, saying: "There has been no impact on the flight-test programme to date as a result of this event."

The airframer says it is "working through a plan" to determine if the failure will have any impact on its year-end first delivery target to the Japanese carrier, as well as determining whether it will conduct the first flight of a production 787 before the R-R investigation is complete.

Boeing says Trent 1000 production engines have not yet been delivered to the final assembly line in Everett, Washington.

Industry sources say the failure, which is believed to have been uncontained, has been initially traced to the single-stage intermediate pressure turbine. The IP turbine in conjunction with the IP compressor supplies the electrical power for the 787's systems.

"A modification is already in place for later engines," says R-R.

With two additional years to mature and improve its 787 powerplant, the manufacturer will introduce a host of improvements with its Trent 1000 "Package B" engines, which will be test flown later this year on Boeing's fourth 787 flight-test aircraft, ZA004, bringing the 62,000-75,000lb-rated (277-333kN) engines within 1% of specified specific fuel consumption.

These changes include a revised six-stage low-pressure turbine design, high-aspect-ratio blades, relocation of the IP compressor bleed offtake ports and fan outlet guide vanes with improved aerodynamics.

Boeing offers a choice of Trent 1000 or General Electric GEnx-1B engines for its midsize, long-range, twin-engined 787.

Source: Flight International