Australia's transport safety regulator has criticised national carrier Qantas over a "cascade of errors" that saw a 1.25-metre tool left in an engine for 300 hours of flying time.

A report released by the Australian Transport Safety Bureau (ATSB) details how maintenance staff "lost" the "turning tool" in an A380's outboard engine, and it was only discovered after it had been cleared for service, flying multiple trips between Australia and the US.

The details were revealed within days of a 737-engine failure that made international headlines, when QF-520 was forced to land with one working engine at Sydney Airport.

Aviation auditor Professor Ron Bartsch formerly served as a manager at the Civil Aviation Safety Authority (CASA) and was once head of safety at Qantas. 

He is concerned airline maintenance staff are overstretched across the sector, and likened the missing tool incident to "an operation where the surgeon leaves one of the instruments inside the body".

A photo shows the equipment in question – a 1.25metre-long nylon turning tool, used during a maintenance procedure called a "borescope inspection" in which engineers visually inspect the inside of the engine, using the tool to manoeuvre it.

'A cascade of errors'

What happened has been described as "a failure on a number of levels and "a cascade of errors, of processes that weren't followed", by ATSB chief commissioner Angus Mitchell.

The ATSB investigation found there was a litany of missed opportunities to address the problem – including flags raised and ignored by Qantas staff – which ultimately resulted in a regulation breach after several procedures were skipped.

The series of events began on December 6, 2023 when Qantas Airbus A380, registered VH-OQI, entered the service hanger at Los Angeles International Airport (LAX) for a three-day scheduled maintenance check.

On the morning of day one, three engineers were assigned to the borescope task, and the turning tool was used to inspect the left engine. 

According to the report, two of the workers were "unfamiliar with the task" and were initially guided by the third engineer. The latter left work early for a medical appointment.

Another team took over the job that afternoon. One of those workers left the tool on the engine inlet assuming it would be needed later. He was wrong.

Later that night the job was marked as complete and an engineer inspected the engine with a torch, checking for "foreign object debris". The engineer missed the turning tool. 

A second engineer completed a second check, also failing to spot the misplaced item.

At the shift's end, after 9pm, an internal report identified that the tool hadn't been returned.

Over the next two days, the ATSB report revealed, all relevant LAX service and aircraft staff were made aware of the situation but the tool was unable to be located.

The Airbus was cleared for service and returned to the skies on the night of December 8. When it landed in Melbourne, despite Qantas staff knowing the tool was missing, the jet wasn't inspected.

The aircraft twice returned to LAX, on December 19 and again on December 28. Again – no checks.

Toward the end of the month, the ATSB report found a Qantas employee entered false information into the airline's digital maintenance system to say the tool had been accounted for – again going against protocol.

On January 1, after flying for 294 hours, the Airbus returned to LAX for the fourth time, and it was then – during routine maintenance – that the tool was found in front of the engine's outlet guide vanes, warped from the pressures of airflow.

No engine damage was reported.

Qantas says it won't happen again

Qantas' head of safety Mark Cameron told 7.30 he didn't believe there was ever any risk to the engine.

"It could have easily dislodged and fallen out on the ground. It wouldn't have caused any impact to the engine itself," Mr Cameron said.

The ATSB refuted that statement.

"Doesn't matter whether it's the tip of a screwdriver or a one, one-and-a-quarter-metre-length nylon tool, regardless of what was the makeup of the tool itself doesn't make it any higher or lower risk," Mr Mitchell said.

Mr Cameron accepts the incident was a failure in process.

"We have worked with our teams ... to understand our training and our processes to make sure that this wouldn't happen again," he told 7.30.

Qantas avoided a fine from the aviation regulator, CASA, which told 7.30 it was "satisfied that Qantas took appropriate safety action in response to the incident, in accordance with their safety management system, and we did not take enforcement action".

Bad look for Qantas?

Qantas though denied that the two incidents within a year hurt its reputation for great safety, as Mr Cameron told 7.30 the way the airline handled the blown engine in Sydney "enhanced" the airline's reputation.

"We know that operational events will will always happen," he added.

"This particular engine has billions of hours of flying across the world. It's one of the most used engines worldwide, and we are constantly making sure that we understand any issues with with the engines to make sure that we can proactively address them ahead of events occurring."

The fault is thought to have originated in the turbine of its right engine – which was almost two decades old and nearing the end of its working life. 

Both Qantas and the ATSB have begun investigations, in conjunction with the engine's manufacturer, GE.

Mr Mitchell says "it's very rare to have seen what we saw the other day, but not unheard of".

"Of the avenues that we look at in our investigation is not only the life of the engine, but its maintenance history as well," he told 7.30.

Qantas said safety for its passengers and crew remained the airline's number one priority.

'A continuous struggle'

While Qantas denies that either incident is part of a "trend", it has been theorised that the industry's maintenance workforce is significantly stretched.

Professor Bartsch said that while the industry is back to pre-COVID levels in terms of passengers, the increased demand for staff is taxing, especially after COVID enforced layoffs. 

"The problem is a lot of people departed the industry, a lot of people were made redundant, some illegally, and the result of that has been a continuous struggle for airlines and a lot of other aviation sectors to actually recruit and retain the number of qualified people to maintain safe operations," he told 7.30.

The union that represents aviation engineers is the ALAEA. It is comprised of 2,000 members. 

President Rod Wyse said engineers will never let an aircraft go into service unless it is "100 per cent safe" but acknowledged the workforce is stretched.

"Ten years is what it takes to become a licensed aircraft maintenance engineer. That's a generally understood or agreed upon period of time," he told 7.30.

"There's a big gap and there needs to be some drastic measures taken to start training.

Qantas said it was ensuring a "pipeline" of skilled workers would be available, with plans to open an engineering academy in 2025 to train the next generation of engineers.

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