More countries ground Max 8 aircraft; Boeing software update due in April

Lauren Eldershaw
By Lauren Eldershaw March 12, 2019 15:03

More countries ground Max 8 aircraft; Boeing software update due in April

As you will have seen this morning, Australia and Singapore are the latest countries to ground Boeing’s 737 Max 8 aircraft following the crash of Ethiopian Airlines flight ET 302 on March 10. Yesterday, the aircraft type was grounded by Indonesia as well as China and Ethiopia. Aeromexico is the latest airline to ground six of its Max 8 aircraft, while the cause of the accident is investigated.

Australia’s Civil Aviation Safety Authority said: “This is a temporary suspension while we wait for more information to review the safety risks of continued operations of the Boeing 737 MAX.”

The action will only impact flights coming into the country from Singapore-based SilkAir and Fiji Airways.

The Civil Aviation Authority of Singapore said that it is evaluating “the safety risk associated with the continued operation of the Boeing 737 Max aircraft into and out of Singapore”.

The governments of both countries state that they remain in close contact with the accident investigation authorities.

Boeing announced yesterday that following the fatal crash of Lion Air Flight 610 in October 2018, the company has been developing a flight control software enhancement for the 737 MAX, which includes updates to the Maneuvering Characteristics Augmentation System (MCAS) flight control law, pilot displays, operation manuals and crew training. The enhanced flight control law incorporates angle of attack (AOA) inputs, limits stabiliser trim commands in response to an erroneous angle of attack reading, and provides a limit to the stabiliser command in order to retain elevator authority. Boeing states that it has been “working closely with the Federal Aviation Administration (FAA) on development, planning and certification of the software enhancement”, which will be deployed across the 737 MAX fleet “in the coming weeks”, adding that the update also incorporates “feedback received from our customers”.

According to the Boeing statement, the FAA anticipates mandating this software enhancement with an Airworthiness Directive (AD) “no later than April”, adding that the FAA is not “mandating any further action at this time, and the required actions in AD2018-23.5 continue to be appropriate”.

A pitch augmentation control law (MCAS) was implemented on the 737 MAX to improve aircraft handling characteristics and decrease pitch-up tendency at elevated angles of attack. It was put through flight testing as part of the certification process prior to the airplane entering service. MCAS does not control the airplane in normal flight; it improves the behaviour of the airplane in a non-normal part of the operating envelope, explained Boeing in the statement.

Boeing stresses that the 737 MAX Flight Crew Operations Manual (FCOM) “already outlines an existing procedure to safely handle the unlikely event of erroneous data coming from an angle of attack (AOA) sensor. The pilot will always be able to override the flight control law using electric trim or manual trim. In addition, it can be controlled through the use of the existing runaway stabilizer procedure as reinforced in the Operations Manual Bulletin (OMB) issued on Nov. 6, 2018”.

Boeing extends its heartfelt condolences to those that lost their lives in the Lion Air and Ethiopian Airlines crash but maintains the 737 MAX “is a safe airplane that was designed, built and supported by our skilled employees who approach their work with the utmost integrity”.

So the upshot from this is that the 737-800 is now total gold dust to anyone with one ready to sell or lease. Indeed an uptick for the 737-700 might follow also if things do not resolve out soon. But as mentioned yesterday, no matter the cause of the accident this week, it is better to be safe than sorry, thus grounding as a precautionary measure does seem to be the wise course of action until the full facts are known. Spare a thought for Silk and other airlines losing significant amounts of income over this whole mess.

Lauren Eldershaw
By Lauren Eldershaw March 12, 2019 15:03