Boeing has confirmed it has completed development and installation of revised 787 electrical systems software on its test fleet, modified after an electrical fire halted test operations last November, sliding the programme's schedule an additional six months.
Ground and flight testing of the final electrical software load - believed to be dubbed version 10.4C - first began in late February on test aircraft ZA003, say programme sources, and was rolled out to the balance of the Rolls-Royce Trent 1000-powered test fleet in March. ZA005 and ZA006, the General Electric GEnx-1B-powered test fleet, completed installation in late April.
Boeing said last week in its quarterly earnings call it is 95% through certification testing the Trent 1000 fleet and 75% through the GEnx-1B aircraft.
Prior to installation of the 10.4C electrical system software, Boeing's 787s were flying on an interim patched version that ensured power distribution in the event of a fault or arc like that seen during the November incident. That interim load allowed ZA004 to return to Boeing flight operations on 23 December 2010. The last of six 787s returned to flight with the interim load on 29 January.
On 9 November 2010, ZA002 suffered an electrical fire while on final approach to Laredo Airport, which caused a loss of power distribution throughout the aircraft, likely due to foreign object debris inside the P100 power distribution panel in the 787's aft electrical equipment bay.
The aircraft landed safely in Laredo, though Boeing halted all test operations for six weeks until an investigation could be conducted and an interim software and hardware solution developed to protect against FOD and the resulting faults.
The result of the six week slip in testing slid first delivery to Japan's All Nippon Airways from early 2011 to the third quarter.