Daily Insight: Friday 21 March 2019: Safety Options and the MAX

News It was disclosed today that some optional equipment related to safety will now be made standard on the Boeing 737MAX. There are two safety-related “options” on the Boeing 737MAX. The first is an angle of attack indicator, which shows the readouts from both of the aircraft’s angle of attack sensors. The second is a disagree alert option, which lights when readings from the two sensors are not identical.Neither of the two aircraft that crashed had those options installed, and even among US carriers, there are differences in installed equipment. American Airlines MAX fleet has both of the options installed, while Southwest has the disagree alert option and an airline installed angle of attack indicator rather than the factory option. United Airlines has neither of these options on its 737 MAX9 fleet.Boeing now plans to install the disagree alert in all 737 MAX models going forward, but not necessarily the angle of attack indicator. Analysis Boeing designed the MCAS system that is used to push the nose of the aircraft down in the event of a high angle of attack to rely on a single sensor. In the event of a failure, it would expect the pilot to shut down the trim system and take over the flight of the aircraft manually. But without an AOA indicator or light showing disagreement between sensors, how are the pilots to know that it is an angle of attack sensor that is providing false input to the system?Reports that Boeing plans to now include the “disagree alert” as standard equipment indicates awareness of the risks of a single sensor input to the MCAS system when a sensor fails, and the lack of an adequate back-up source of data for their automated flight laws. One of the key questions that must be asked is how the 737 MAX was ever certified with a system that relied on one and not multiple sensors, had no provision to address a sensor failure, and compounded the problem through not including those issues in transition training. A criminal investigation has been opened by the FAA, given that 346 lives were lost during a rush to production. The design of the MCAS system and its approval continues to defy explanation in an industry where redundancy to protect safety is a cardinal rule. Insight The reports on the standardization of safety equipment come from an unidentified insider at Boeing speaking off the record to reporters. That in itself, says a lot. But if Boeing adds the safety equipment as standard equipment, does that reflect negatively on the FAA's certification processes and that the aircraft without that equipment were less safe that those with them? Lawyers and international regulators will have a field day with this, and the FAA may be forced to step-up its oversight responsibilities to rely less on Boeing employees and more on independent staff.Adding the disagree alert to the MAX, along with increasing the sensor inputs to MCAS and software revisions to reduce the trim travel and rely on two inputs may still not be enough to satisfy international regulators. After two crashes, pilot simulator training on what to do in the event of an MCAS system failure may also be in the cards, which will increase costs to both Boeing and its airline customers.The real question Boeing needs to answer is why equipment that is related to safety of an aircraft is ever made “optional” rather than standard? The lapses in judgment at both Boeing and the FAA that enabled a non-redundant system to be installed in the 737 MAX are under further investigation. One thing is certain. The world has lost trust in the FAA, and the way aircraft are certified will likely never be the same again. Major changes are in the wind, and appropriately so.

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