Questions about the safety of Boeing’s newest planes are mounting after the latest grounding of its jets, and while no airlines operate them to Australia, models from the same controversy-plagued generation of aircraft are already in local skies.
The latest saga surrounding Boeing’s 737 Max aircraft began last week, when an Alaska Airlines Max 9 was forced to make an emergency landing back at Portland airport because a panel plugging an unused exit door blew out minutes after takeoff.
Fresh concern about the installation of the door plugs led to the grounding of all Max 9s featuring the panels with subsequent inspections finding numerous examples of loose bolts on other models.
The issues come just a few years after the Max 9’s slightly shorter sibling, the Max 8, was banned from skies globally for almost two years after two fatal crashes in 2018 and 2019 linked to design flaws.
While the 737 Max planes that are flown in Australia are among the most scrutinised aircraft in the world and adhere to strict local regulatory standards, Boeing’s processes will now be subject to a fresh investigation – separate to the probe into the Alaska Airlines incident – in the US.
What have been the Boeing 737 Max’s issues?
The Max is the fourth generation of the Boeing 737, a plane first flown commercially in 1968. Designed to compete with the Airbus A320Neo, the Max was seen as a modern update to bring a more fuel-efficient model to the 737 family while largely retaining the decades-old structure of the plane.
This approach appealed to airlines because pilots who already flew the 737 wouldn’t have to retrain to operate a Max. Boeing achieved the greater fuel-efficiency in part due to heavier engines.
However, crash investigators identified faults in the sensors and new flight control software to compensate for the heavier engines needed for the Max as causing the planes to plunge from the sky.
The Manoeuvring Characteristics Augmentation System (MCAS) – anti-stall software which was designed to keep the aircraft stable in flight – had not been explained to pilots, who found themselves in a doomed struggle to control their aircraft when the system overrided pilots and directed the nose of their planes downwards.
Boeing was hit with US$2.5bn in fines and compensation, and is estimated to have lost tens of billions more in lost orders for planes. Australia’s regulator, the Civil Aviation Safety Authority (Casa) has since deemed the Max 8 safe for operation.
The latest saga involving the Max 9 relates to a panel plugging an exit door that features on the slightly longer versions of the plane, the Max 9 and Max 10, but not most versions of the Max 8.
The Alaska Airlines plane – which had been delivered just weeks earlier – was configured with fewer seats, meaning it required fewer emergency exits. As such, the mid-cabin exit was plugged with the panel that would ultimately blow out.
The US National Transportation Safety Board is still examining why the door panel in the middle of the plane’s fuselage blew out, leaving a hole “the size of a refrigerator” in the side of the plane. The force of decompression in the plane was so strong it blew open the cockpit door, Reuters reported, citing a person briefed on the investigation.
Do any airlines fly the Max 9 in Australia?
No. There aren’t any Australian airlines that have taken delivery of a Max 9 aircraft, nor do any international carriers fly the single-aisle plane designed for short- and medium-haul flights on Australian routes.
What about other Max planes in Australia?
Virgin Australia and fledgling budget startup Bonza currently operate the Max 8 aircraft, and are expecting to take delivery of more in coming months and years as airlines look to become more fuel-efficient for cost and environmental reasons.
Bonza has six planes in its fleet, all of which are Max 8 aircraft.
Virgin Australia has taken delivery of three Max 8s so far, with 11 more on order expected over the course of 2024.
Virgin Australia has also ordered 25 Max 10, an even longer variant that could be configured in a way which could feature the same door plug at the centre of the Max 9 investigation. Virgin’s Max 10s are expected to begin arriving from the end of 2025. Investigations into the Alaska Airlines incident are likely to have concluded by the time the Max 10s make their way to Australia.
Should I be worried about flying on a Max plane?
In Australia, the broad consensus is no. Casa has said it is watching and waiting to see what happens in the US and other countries where Max 9s are flown and currently being investigated.
As for the Max 8, the only one currently flown in Australia, Casa has deemed this plane safe. The Max 10, which Virgin is expected to take delivery of from 2025, is yet to receive regulatory approval.
Dr Sonya Brown, a senior lecturer in aerospace design at the University of New South Wales’ school of mechanical and manufacturing engineering, says aviation in general remains safe, in part due to the strong regulatory standards as well as the intense scrutiny manufacturers and airlines come under after each incident.
Brown says the incident last week and discovery of more loose bolts on other planes could mean standard maintenance schedules for the Max are beefed up – something which should help confidence in the aircraft.
Regarding the safety of all Max aircraft, Brown stresses that as current indications suggest an installation issue occurred on the Alaska Airlines Max 9, at this stage it should not raise the same concern that occurred after the fatal Max 8 crashes, which she says “were the most concerning issues I’ve seen in my time”.
“The current issue is just so completely separate from that,” Brown says.
What is Boeing’s reputation now?
In recent days, the Federal Aviation Administration (FAA) – the US regulator – announced a formal investigation “to determine if Boeing failed to ensure completed products conformed to its approved design and were in a condition for safe operation in compliance with FAA regulations”. It came after numerous reports of loose bolts discovered during inspections of grounded Max 9s.
While aviation experts are cautious not to link the design issue that caused two fatal Max 8 crashes with apparent door plug installation issues and loose bolt findings on the Max 9, they acknowledge a concerning run of events at Boeing in recent years.
“I sincerely hope that Boeing has learnt significant lessons particularly around redundancy of flight critical systems,” Brown said. “I’d be very surprised if such a large mistake like what happened with the MCAS system was made again.”
Some industry insiders have held concerns that the approach to designing and constructing the Max generation, and structural changes at Boeing to outsource key parts of the production line, are too heavily influenced by commercial concerns and have ultimately seen standards slip.
One aeronautical maintenance engineer and safety expert, who has previously worked with Boeing during a decades-long career in the industry, says that while he doesn’t believe the Max 9 revelations point to a safety crisis, the manufacturer needs to address stubborn internal cultural issues.
“You can very clearly make an argument that the Max 8 and Max 9 issues are distant and separate, but at the end of the day these are repeated issues from the same company on the same generation of aircraft,” says the expert, who asked not to be named due to the sensitivity of the issue and size of Boeing in the industry.
“It goes to cultural issues, outsourcing has brought a whole bunch of new problems with standards … The evidence indicates this is all in-house Boeing stuff, given how new the plane was.”
“Boeing needs to demonstrate to the industry at large and the flying public that their cultural issues are sorted,” the expert said.
How to know if you’re booking on a Max plane?
For those who are not put at ease by the regulator’s stamp of safety and are still uncomfortable with the Max generation, it will become increasingly tricky to avoid flying on the planes as airlines take more deliveries in coming years.
Qantas and Rex don’t operate any Max planes, nor do they have any on order.
Bonza only flies Max 8s and has not announced any intention to acquire other model aircraft.
Virgin currently flies its Max 8s on a range of different routes, including between popular destinations including Sydney, Melbourne, Perth and Brisbane as well as its limited international offerings such as between Cairns and Tokyo.
Booking through certain websites, including Google Flights, will display the aircraft model of a flight.
However, airlines commonly shuffle around aircraft. Additionally, cancellation rates on some busy routes, particularly Sydney-Melbourne, are as high as one in 10 across all airlines, and being moved to a slightly earlier or later flight is common, meaning attempts to book on a service not scheduled to be flown on a Max 8 is no guarantee.
