A Boeing 787 engine involved in a contained failure on the ground earlier this week has been identified as belonging to the originally-certified production standard.
The 29 July incident now under investigation by the US National Transportation Safety Board (NTSB) involved a Block 4 version of the GEnx-1B, according to General Electric The Block 4 is the version that falls short by 2.4% of Boeing's target for specific fuel consumption (SFC).
In late 2011, GE certified a new, more efficient version of the engine called the performance improvement package (PIP) 1.
The Block 4 engine that failed during the runway taxi test sprayed internal components from the low-pressure turbine on a grassy area near the runway, which ignited a fire on the grounds of the airport in North Charleston, South Carolina.
Boeing tests aircraft built at the 787 final assembly plant in North Charleston before delivering the aircraft to the customer. In this case, the customer is Air India.
The low-pressure turbine was a major focus area in the PIP 1 upgrade. As part of the effort to improve SFC performance, GE increased the number of blades in the low-pressure turbine stages.
The components retrieved from the damaged Block 4 engine are now being analysed in a metallurgical laboratory at GE's main engine factory in Cincinnati, GE says. The specific identities of the components of the low-pressure turbine have not been disclosed.
The Block 4 engine has been removed from the wing of the 787, and transported to Cincinnati to be inspected by NTSB investigators.
Boeing and GE say they are unaware of any issues that could affect the 80 GEnx engines currently in service, which includes four GEnx-1Bs installed on two Japan Airlines 787s and all GEnx-2Bs flying on Boeing 747-8s.