FAA on Friday issued its version
of the directive requiring Boeing 777 operators to modify Rolls-Royce Trent 800 engines to minimize the risk of ice build-ups that can lead to fuel flowage problems and, in rare instances, in-flight shutdowns.
The AD is based on an EASA directive issued in July
, which came out just days after Rolls-Royce issued an alert service bulletin detailing the recommended fix. The problem was spotlighted in the probe of the January 17, 2008 crash
of a British Airways Boeing 777 at London Heathrow.
FAA's directive gives operators of about 70 N-registered 777s 6,000 flight hours from the AD's Jan. 4, 2010, effective date or until Jan. 1, 2011, to replace fuel-to-oil heat exchangers (FOHEs) with new, modified designs.
The FAA's compliance window is larger than EASA's. The July 13 EASA AD requires replacing the FOHE within 6,000 flight hours from July 10, 2009--the day the Rolls-Royce bulletin was published--or before Jan. 1, 2011, whichever occurs first.
ALPA, in comments on the AD's draft version
, asked FAA to make the compliance time a bit tighter, suggesting operators be required to make the modifications "within six months after the effective date of the AD or within 6,000 flight hours after receipt of the service bulletin.'' FAA declined, saying that procedures mandated by AD 2009-05-11, published March 5, 2009
, provide "adequate" procedures to address in-flight problems "until hardware modifications become available."(Note: post updated to reflect proper number of aircraft affected by the AD, which lists "about 138 products" -- or engines.)