Qantas pilot questions Airbus' explanation for A320 malfunction as fuselage panel issues uncovered

Following the grounding of 6000 Airbus A320s this weekend, an ex-Qantas pilot has questioned the manufacturer’s explanation for the issue.

An incident on a JetBlue flight in the US on 30 October prompted a downgrade in a software update that was intended to protect against in-flight loss of control. It was revealed that “intense solar radiation” caused a malfunction in the elevator and aileron computer on the aircraft, resulting in 6000 around two thirds of the fleet being grounded for a software fix.

Kevin Sullivan was the captain of a Qantas flight that suffered two computer-generated pitch down events in October 2008, which injured more than 100 passengers. Captain Sullivan, who captained flight QF72 on an A330, told The Australian that the uncommanded drop in altitude he experienced on flight QF72 was never fully explained, with the Australian Transport Safety Bureau (ATSB) ruling out solar radiation after exhaustive tests.

“It took the ATSB three years to determine that cosmic or solar radiation was not the cause of the poor behaviour of the flight control system on the A330. But Airbus has concluded in one month that it can cause abnormal effects of the A320 aircraft, specifically for aircraft recently updated to operating system L104,” said Captain Sullivan, who retired from Qantas in 2016.

“I am sceptical. Is the cause of ‘solar radiation’ a smoke screen for a bigger issue? It is up to Airbus to answer that.”

Software upgrade

In an emergency airworthiness directive, the European Aviation Safety Agency made it clear aircraft affected were those that had undergone the software upgrade, from L103+ to L104.

“This condition, if not corrected, could lead in the worst-case scenario to an uncommanded elevator movement that may result in exceeding the aircraft’s structural capability,” said the EASA directive.

A spokesman for Airbus said the decision to revert to a previous software version was due to the need for an “extremely prompt reaction” to a single event with potential unsafe consequences.

“Following analysis of the JetBlue in-flight event, and in liaison with airworthiness authorities, it was indeed determined that atmospheric radiation let to an SEU (single event upset),” said the spokesman.

“This was the first time we have seen such an occurrence on an A320 family aircraft.”

He said the L103+ software was known to be resilient to this kind of event. “This will not have any implications for the ongoing operation of the (A320) aircraft,” the spokesman said. “With reference to the A330, A350 and A380 our analysis does not show similar vulnerability within these families.”

Captain Sullivan said there were obvious similarities between the JetBlue pitch down event and the QF72 upset, except for the fact A330s were not grounded in the wake of the 2008 incident. He said both events highlighted the complexity of computer-controlled fly-by-wire aircraft that are “easier to fly but harder to save”.

“When the automation malfunctions, pilots are left in a ‘no man’s land’ of abnormal operation that they may not have been trained to address,” Captain Sullivan said. “Increased automation can increase the risks of unforeseen consequences; complex systems can fail in complex ways.”

A National Transportation Safety Board investigation into the JetBlue incident is continuing. The majority of the 6000 A320s grounded in response to the incident are back in the air, after undergoing the software fix over the weekend. An Airbus update issued late Monday said the manufacturer was working with airline customers to support the modification of less than 100 remaining aircraft to ensure they can be returned to service.

Fuselage panel problems

Meanwhile Reuters has reported that Airbus had found quality problems affecting the fuselage panels of several dozen A320-family aircraft, delaying some deliveries. There were no indications that any had reached aircraft in service.

“Airbus confirms it has identified a quality issue affecting a limited number of A320 metal panels,” it told Reuters. “The source of the issue has been identified, contained and all newly produced panels conform to all requirements”.

A spokesperson said the problem stemmed from a supplier, who they declined to name. Airbus has internal and external suppliers for its aerostructures, with the front of the A320 fuselage broadly made in France and the rear in Germany. Upper panels tend to be produced in-house with the rest involving multiple suppliers.

The quality problems emerged as Airbus is beefing up efforts to meet challenging delivery targets for the year and followed lower-than-expected indications for deliveries in November.

A person with direct knowledge of the matter said some deliveries were already being impacted, but there was no immediate confirmation of how many nor for how long. One source told Reuters the total number of jets affected was around 50.

How badly the flaw affects deliveries and whether the impact will fall in the current year or in 2026 depends where on the aircraft the problem is located, and on how serious it is.

Airbus said “only a portion” would need further action.

Worldwide more than 12,500 aircraft in the A320 family are in operation, making them the most common commercial passenger plane. It recently ousted the Boeing 737 as the most-delivered jetliner.

More: The Australian, Reuters