Taking it to the MAX

Looming at the centre of the MAX investigation is the Manoeuvring Characteristics Augmentation System, or MCAS. In very simple terms it would appear that the MCAS was introduced on the MAX to counter the different flight characteristics stemming from the repositioning of the larger engines of the new 737. It is a system designed to sit passively below the operation unless a stall situation is imminent at which time it would intervene without the need for pilot input. If MCAS activation is definitively found to be the cause, then the reason behind why the aircraft intervened and commanded the stabiliser to pitch the jet’s nose down will be critical. That road is still ahead of us at this time.

What has occurred is a prompt response by the industry to ground the aircraft. Like the dawn of the jet age when the deHavilland Comet tragedies saw the type removed from the skies, the MAX now awaits the outcome of the investigations with no specific timeframe able to be applied. However, it is once again a positive for a proactive industry to take such a step globally.

Sure, there was a delay in grounding the type in the United States, but one would be naive to think that there weren’t more elements in play in the land of the MAX’s manufacture. Even so, the tough call was ultimately made, and the 737 MAX was withdrawn from operation in the US.

Once again, we have seen armchair experts throwing up one cause after another before the verdict is finally reached when it would appear to be a case for James Reason’s Swiss Cheese model. Like analysing an individual accident, perhaps we can view the situation with the MAX and its MCAS in a similar light.

The system was born of a need to improve the power plants on the existing 737, however there just wasn’t enough space beneath the wing to fit them. Consequently, they were moved forward and up, which changed the aerodynamics of the aircraft. So was the MAX’s problem rooted in the commercial need to match Airbus and the neo? Were the aerodynamic changes and systems involved too complex to be a modification on an existing type? Did they warrant an entirely new aeroplane? Much has been written about the piloting aspect from a range of perspectives including speculation around the low time first officer and a degradation of the handling skills of pilots as automation has increased.

Neither of these debates are new to the conversation. Pilot training has also been a point of scrutiny as the ‘differences’ course for the MAX was minimal and it would seem, without a requirement for simulator or line training. Was this a commercial consideration for airlines, or was the MAX truly just so similar to its NG predecessor it wasn’t necessary? Also, it would appear that even in the books there was no particular system description regarding the new MCAS.

Was there a software problem? Or a components problem? Or a manufacturing problem? Was the Angle of Attack sensor transmitting erroneous information to the MCAS causing it to intervene? Only now are the first indications beginning to filter through.

Was the certification process thorough enough? There are so many unanswered questions – not just one. And these are what the investigations will seek to answer.

Until that time, it is all in the preliminary stages even though there are some strong indicators in play.

For the time being, the MAX will remain grounded at great cost and inconvenience to the airlines, although once again it demonstrates the aviation’s proactive approach to safety. For now, we wait for official findings but it is doubtful that one factor alone will prove to be the villain. Aviation is a complex beast and when something goes wrong, there are usually many contributing elements dating back to the earliest of origins, long before the final impact.

For the sake of all parties and the safety of the travelling public, a cause and a resolution will be found in whatever time it takes to achieve.

This is not an air-bag recall on a motor vehicle which rolls the onus of rectification onto individual owner/ drivers, with the option to ignore the issue at their own risk. An answer will ultimately be found and, as costly as it may be, a solution will be implemented worldwide. Undoubtedly, the immediate consequences for Boeing are farreaching, but for air travel they are even greater.

The tragedies of the loss of the two 737 MAX aircraft will stay with individual families forever. For the industry, it must regroup, recognise shortcomings, self-examine, improve and move forward, as it has done before.

Importantly, we must never forget any lessons that will be learned.

Safety must remain front and centre – Cabin Pressure, Page 79.

‘We have seen armchair experts throwing up one cause after another’