Sir - After months of rigorous testing to obtain certification, and subsequently testing clearance, for extended-range twinjet operations, you report in the article "Compressor damage grounds two of BA's 777 fleet" that the General Electric GE90 has had to be removed from British Airways 777s, having suffered compressor damage following the failure of a manifold (Flight International, 5-11 February, P10).
That a failure of this nature should occur so soon after entry into service is in itself surprising. That GE seems to have been aware of the possibility - a design solution had already been produced - is astonishing.
Obviously, there has to be a judgement as to when a modification should be introduced, but, on a quality basis, it appears that this change should have been immediate, both from safety and cost considerations.
D F NEWLAND
Watford, Hertfordshire, UK
Source: Flight International