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FAA snubs NTSB, ALPA requests on Rolls-Royce 777 engine ice directive
By John Croft
In a final airworthiness directive (AD) to be published Friday, the FAA has rebuffed efforts by both the Air Line Pilots Association International (ALPA) and the US National Transportation Safety Board (NTSB) to acclerate a mandated hardware fix with a 2011 deadline for Boeing 777 operators with Rolls-Royce Trent 800 turbofan engines.
The action stems from the crash of a Rolls-Royce-powered Boeing 777 at Heathrow Airport last year in which accumulated ice in the engine's fuel-oil heat-exchanger (FOHE) is suspected of blocking fuel flow to both engines. The same phenomena likely caused a similar in-flight incident with one engine of a Delta Air Lines 777 in November of 2008.
An interim AD issued in March of this year called on operators to follow certain operational guidelines designed to prevent ice from forming, including in-flight and ground measures.
European regulators in July mandated that airlines close out the interim AD by equipping aircraft with a redesigned Rolls-Royce FOHE, a device that is supposed to cool the engine oil while at the same time pre-heating the incoming fuel to prevent any water present from freezing. EASA gives operators 6,000 flight hours from July or until 1 January 2011 to make the fix, whichever occurs first.
The FAA final AD to be issued Friday gives operators the same lead time, with the clock starting in early January.
However, ALPA and NTSB have expressed concerns over potential safety issues during the compliance period.
In comments to the proposed rulemaking, issued in July, ALPA requested that the compliance time be set as soon as six months after the January effective date for the AD as interim procedures call for "an immediate idle descent to melt the blockage" in the case of an engine rollback.
Union concerns include the potential for traffic conflicts during such descents in remote areas with no radar separation.
"This engine rollback is very insidious to the crew and creates the potential for a pilot to be faced with an immediate descent without adequate time to compensate for traffic, weather, or terrain," ALPA states.
Fearing similar incidents, NTSB had called on the FAA to mandate that at least one engine on each affected aircraft be modified with the redesigned FOHE by the end of December this year.
"The NTSB believes that the January 1, 2011 compliance date for installation of the new FOHE is not consistent with the risk associated with the original FOHE design."
The FAA rebuffed both requests however, telling the organizations that the interim operational procedures would "assure continued safe operation until hardware modifications become available".
FAA allows Boeing 777s to fly with glitch into 2011, WSJ reports
UPDATE: Boeing response added below.
The Federal Aviation Administration will allow more than 130 Boeing 777s to continue flying long distance through early 2011 with suspect parts that "have caused engines in extremely rare instances to ice up and basically shut down in midair," The Wall Street Journal reported Monday.
The issue concerns "ice plugging up certain internal piping parts and restricting fuel flow to engines built by Rolls-Royce PLC, particularly during extended, high-altitude flights crossing polar regions," The Journal said. It said this has happened just three recorded times, including on a British Airways jet that crashed short of a runway at London's Heathrow Airport in January 2008, injuring 13.
Critics, including the National Transportation Safety Board, have urged faster action, The Journal reported. It said the FAA delayed in part because of limited availability of replacement parts and because it determined interim safeguards are adequate to ensure safety.
Boeing responded to the report with a statement saying:The Journal said Rolls-Royce has indicated it is cooperating with Boeing and Airbus, which also uses its engines.
Boeing welcomes the issuance of this rule. While the conditions that the rule addresses are extremely rare, the interim procedures developed and mandated earlier this year were specifically put in place to mitigate against the effects of ice in fuel until retrofit of the new hardware. Once the new hardware is in place, the interim procedures will be removed. This assures the continued safety of the 777 fleet whether or not the new hardware has been installed.
http://blog.seattlepi.com/aerospace/archives/191873.asp#extendedFor sale: Airbus A320 pulled from Hudson
The U.S. Airways A320 that pilot Chesley B. Sullenberger III landed safely on the Hudson River after a bird strike in January is up for sale.
"Aircraft suffered severe bird strike event resulting in water emergency landing," reads the auction listing by Chartis Aviation Salvage. "Severe water damage throughout airframe. Impact damage to underside of aircraft."
The aircraft is for sale "AS IS/WHERE IS" (in Kearny, N.J.) and engines are not included. People can bid through March 27.
BA 777 crash: Quick flap retraction avoided ILS collision
By David Kaminski-Morrow
Investigators believe the British Airways Boeing 777-200ER which crashed at London Heathrow would have struck the ground earlier, potentially colliding with the instrument landing system antenna, had the pilot not partially retracted the flaps on approach.
The final report into the accident shows that the aircraft's flaps were at 30° before ice flushed through the fuel lines choked off the fuel flow to both engines.
As the aircraft descended to a height of about 240ft, the captain retracted the flaps to 25°. The Air Accidents Investigation Branch concludes that this enabled the aircraft to glide an extra 50m (160ft) before touching down.
"The action of reducing the flap setting was prompt and resulted in a reduction of the aerodynamic drag, with a minimal effect on the aircraft stall speed," it states.
If the twin-jet's flaps had remained at 30°, the AAIB adds, it would have cleared the Heathrow perimeter fence but landed before the ILS antenna, probably resulting in a collision.
"The effects of contact with the ILS antenna are unknown but such contact would probably have led to more substantial structural damage to the aircraft," it says.
Flight BA038 came to rest at the threshold of runway 27L after arriving from Beijing on 17 January 2008. While the aircraft was badly damaged, all of the passengers and crew members on board survived.
European safety regulators have identified another suspected dual-engine icing event, involving a Rolls-Royce-powered Airbus A330, and ordered precautionary measures centred on the water scavenge system.
During take-off, the aircraft's right-hand Trent 700 engine suffered a temporary shortfall in engine thrust - prompting an 'engine stall' warning - before it recovered.
Investigation showed that fuel flow to the right-hand engine had been restricted. But it also determined that the left-hand engine had experienced a similar flow restriction shortly afterwards.
This thrust shortfall on the left-hand engine had been "insufficient to trigger any associated warning", says the European Aviation Safety Agency, adding that it was "only noted through analysis of the flight data".
After the initial 'engine stall' warning on the right-hand powerplant, the pilots responded with standard procedures, which included retarding the throttle to idle.
No action was required to restore thrust on the left-hand engine. Both engines recovered fully and the remainder of the flight was uneventful.
EASA has not disclosed the identity of the carrier or the location of the incident, describing it only as a "recent in-service event".
But it says: "Based on previous industry-wide experience, the investigation of the event has focused on the possibility for ice to temporarily restrict the fuel flow."
While no fuel system fault has been identified, EASA says the operation of the water-scavenge system, located at wing rib 3, "cannot be excluded" as a contributing factor.
EASA has issued an emergency airworthiness directive ordering the operators of Trent-powered A330s to deactivate the automatic standby fuel pump scavenge system which operates during taxiing and take-off. It is also prohibiting dispatch of aircraft with any main fuel pump inoperative.
"Testing and analysis are continuing to identify the root cause of the event," it adds.
Restriction of fuel to the engine, as a result of ice accumulation, has become a high-profile concern since the dual-engine accident involving a Trent 800-powered British Airways Boeing 777 at London Heathrow in January 2008.
Ice-related fuel restriction on Trents is also suspected in single-engine incidents involving a Delta Air Lines 777 in cruise and an Etihad Airways A330 during a go-around at Manchester.
EASA has already mandated a modification to the fuel-oil heat exchanger in Rolls-Royce Trent 800, 700 and 500 engines. It has not been confirmed whether or not the A330 involved in the incident had been modified