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HONG KONG — In an customer memorandum dated Wednesday, November 17, Airbus’s Toulouse-based Flight Safety Department issued an incremental update to its findings on Qantas Flight 32. The brief memo is a clear, if not directly stated, defense of the A380’s redundancy following the QF32 investigation into the uncontained failure of the aircraft’s number two Trent 900 engine.

The report also adds additional technical color on the state of the aircraft after the engine failure and its publication comes a day after other internal Airbus reports were leaked illustrating the extent of the damage sustained by VH-OQA.

A380 / RR TRENT 900 – QANTAS VH-OQA INCIDENT ON 4th NOVEMBER 2010.

FROM : AIRBUS FLIGHT SAFETY DEPARTMENT TOULOUSE

Subject: A380 / RR Trent 900 – Qantas VH-OQA incident on 4th November 2010

Our ref.: QF32 AIT 3, dated 17th November 2010

This AIT is an update of the AIT 2 following the in-flight engine failure during flight QF32 from Singapore to Sydney, on 4th November 2010.

This AIT has been approved for release by the Australian Transport Safety Bureau (ATSB) who leads the on-going ICAO Annex 13 investigation.

The second RR inspection program applicable to the Trent 900 engine family and covered by EASA Engine Airworthiness Directive has been published allowing continuous operations of the fleet. Together with its partners, Airbus is providing support to the operators for engine logistics to minimize interruptions to the fleet.

One single high energy fragment is considered from a certification requirement viewpoint. The damage assessment has established that the IPT disk released 3 different high energy fragments, resulting in some structural and systems damage, with associated ECAM warnings. Therefore the crew had to manage a dynamic situation.

Despite the situation, amongst the various available systems supporting the crew to operate the aircraft and return safely to Singapore were:

– Flaps remained available (slats were jammed retracted).

– All flight control surfaces remained available on the pitch and yaw axis.

– The roll control was ensured through: (a) on the left wing: inner aileron, spoilers 1, 3, 5 and 7; (b) on the right wing: mid and inner ailerons, spoilers 1, 3, 5, 6 and 7.

– The flight control laws reverted to Alternate law due to the loss of the slats and of some roll control surfaces. Normal law was kept on longitudinal and lateral axes.

– Flight envelope protections were still active.

– The autopilot was kept engaged till about 700 feet Radio Altimeter, time at which the crew took over manually. Flight Directors were ON.

– Manual control of engines 1, 3 & 4 was maintained till aircraft stop.

– Landing in SIN took place about 1 hour 40 minutes after the engine 2 failure with flaps in
configuration 3.

– Normal braking was available on both body landing gears with antiskid, and alternate braking without antiskid on both wing landing gears. The crew modulated braking in order to stop close to emergency services.

– After the aircraft came to a stop, the reason engine 1 could not be shut down has been determined: 2 segregated wiring routes were cut by 2 out of the 3 individual disk debris.

Airbus continues to work in support of the on-going investigation to complete the detailed analysis.

An update to operators will be provided as soon as further consolidated information is available.

Australian reporter Ben Sandilands has published an extraordinary visual and technical account of the damage sustained by VH-OQA when its number two Rolls-Royce Trent 900 engine suffered an uncontained failure on November 4 six minutes after takeoff from Singapore’s Changi International Airport. Sandilands’ report originates from the preliminary Airbus assessment for the Australian Transportation Safety Bureau (ATSB) investigation into incident aboard Qantas Flight 32.

The document’s authenticity has been confirmed by Airbus.

The explosion, now traced to an excessive oil build up in the intermediate and high pressure turbines of the Trent 900 engine, caused engine debris to be violently expelled into the surrounding structure of the A380.

Airbus has grouped the damage to VH-OQA in several main areas,
including to “perforations” to the aircraft’s wing, which entered in the
bottom skin of the wing and exited the upper skin. Additionally, two
additional perforations were sustained to the lower panel of the wing, as well as the belly fairing and inboard flap track fairings.

The first, and larger, of two major punctures was suffered by the droop nose 2 on the wing’s leading edge structure. In the line of fire was the drive motor for the droop nose which was “badly damaged” and “seems ot [sic] have been on the direct path of trajectory through the wing.” The debris entered in front of wing rib 13 on the lower panel and exited at the topskin just in front of rib 12.
 
The second major puncture came as engine debris tore into the lower side of the droop nose panel, and continued its path through the front wing spar (CATIA rendering pictured above). As the debris transited the A380’s wing structure, a fuel pipe and wiring were severed near wing rib 9 where it exited.

Additionally, the lower skin on wing panel 1 was punctured in two locations, causing a leak in the A380’s left wing inner tank. The first, was at rib 7 at stringer 0 and the second at rib 10 and stringer 6.

The result of the punctured fuel tank was a steadily increasing imbalance in the aircraft’s center of gravity as the left wing tank emptied its contents over Batam Island.

Immediately following the explosion in the number two engine, the crew was presented with 53 electronic centralized aircraft monitor (ECAM) messages, including the confirmed failure of the A380’s green hydraulic system. The severed wiring also appears to have locked out control of engine number one to the crew.

Sandilands addresses the questions of the A380’s system redundancy directly, writing:

“The wing of the jet shows remarkable structural strength in sustaining damage that might have destroyed the airliners of earlier decades, but the questions as to whether control system revisions are necessary to deal with some of the consequences in terms of failed hydraulics and fuel imbalance are said to be very actively under consideration.”

The ATSB plans to release its preliminary factual report on December 3.

ZHUHAI — Few companies on the planet are as disciplined as Boeing with their words, so how the US airframer chooses to express itself can illuminate how the company’s leadership is thinking. Boeing released its third statement Tuesday on the November 9 fire that occurred while ZA002 was on approach to Laredo, Texas. The most important line in the statement at first pass is positive for the 787, taking a glass-half full approach to system redundancy.

“The incident demonstrated many aspects of the safety and redundancy in the 787 design, which ensure that if events such as these occur, the airplane can continue safe flight and landing”.

Morgan Stanley aerospace research analyst, Heidi Wood, reads between the lines, remarking:

“The vagueness alerts us, as it sidesteps claiming the systems all worked. This tells us the multiple redundancies may not have performed as they should have, which dovetails with what our sources have been asserting. We’re impressed by the honest admission; we believe this is an FAA chief concern. “

Exactly what redundancy was not provided after the P100 panel failed is unclear at this point, but Wood does not expect the flight test fleet to return to testing anytime soon, estimating a December or January resumption of the certification campaign, which “could push first delivery to 2012” with changes to aircraft hardware and software.

ZHUHAI — With six 737s with Boeing’s new Sky Interior now handed over to airlines, the airframer is looking ahead to what’s next and may be turning its attention to updating the narrowbody’s front office.

ZHUHAI — Rolls-Royce, beset by criticism over its public handling of the uncontained failures of its Trent 900 and 1000 engines, has canceled its planned Airshow China show briefing.

The engine-maker offered no explanation for the cancellation, leaving media attending the show only to speculate on its sudden change of plans.

ZHUHAI — It’s very late here in China at the moment. Wanted to do a very quick post on ZA001 and ZA005 heading home to Boeing Field from Rapid City, South Dakota and Victorville, California, respectively. Following the ferry flights to BFI, the fleet will remain grounded. Flightglobal has the latest details on the ZA002 fire investigation.

ZHUHAI — At a briefing and announcement at Air Show China Tuesday morning, Comac announced an order for 100 narrowbody C919 aircraft to Air China, China Southern, China Eastern, Hainan Airlines, CBD Leasing and GECAS.

While foreign journalists were banned from the event hosted by state-owned aircraft maker Comac, a side door was left ajar prior to the commencement of the event. Though it was staffed with a police officer, some journalists, includling this one, were provided an unobstructed view of a marketing film for the C919 produced by Comac. Most notably was the presentation of the latest specifications of the new aircraft, but also featured six models that are planned.

These models included the single-class 168-seat (156-seat two class) baseline model, as well as stretched, shrunken, freighter, business configuration and “special” variants. With these plans revealed, Comac’s six models appear to be readying for competition against Boeing’s 737-700, -700C, -900ER, BBJ and Airbus A319, A321, A320P2F and ACJ.

Air India’s first 787 Dreamliner, registered VT-ANA, has been moved from the paint hangar to the Everett flight line. Airplane 25 is slated for a second quarter 2011 delivery to the Indian flag carrier.

Photos Credit Moonm