THE GENERAL ELECTRIC GE90-powered Boeing 777 test aircraft resumed certification flight-testing on 20 July, following formal US Federal Aviation Administration approval of the new engine hardware and software modifications.
The aircraft was grounded after a bird-strike test on 30 May revealed design problems with the platform spacers between the fan blades. At the same time, revised software was also being developed for the engine's electronic control-system, to correct a compressor surge, which had been caused on 4 May by scheduling problems with the variable-guide vanes.
New spacers and software were installed on the GE90-powered 777, which resumed flying on 16 July. On 18 July, the new software was validated when the test aircraft duplicated the take-off sequence leading to the original surge without causing a repeat performance.
The 20 July flight is the first since 30 May, which will count towards certification. This was originally scheduled for August, but GE and Boeing are racing to try and certificate the GE90 777 before the planned first delivery to British Airways on 15 September.
Source: Flight International
