Following two fatal crashes and the eventual grounding of the Boeing 737 Max 8 aircraft, it has been revealed that the plane had two safety features that were sold as optional extras. The New York Times reveals that the additional sensors would have checked on data collected by existing sensors, and could have alerted pilots to potential issues.
Specifically, the 737 Max 8 of Lion Air and Ethiopian Airlines lacked an “angle of attack (AOA) disagree” light. To clarify, the AOA sensors essentially detects if the plane is about to stall, based on the direction the plane’s nose is pointing in relation to the airflow. And when two AOA sensors present data that don’t match, the AOA disagree light will light up to indicate so.
Another feature that was missing was an AOA indicator. Unlike the AOA sensor, the indicator is designed to translate the data from AOA sensors into a visual representation.
A source close to the New York Times also said that the AOA disagree light will be added as part of an update to the MCAS. The update in question is expected to be deployed by the end of April, and will also have the MCAS take readings from both AOA sensors instead of just one. That said, it looks like the AOA indicator will remain an optional extra.
These are just two items on a list of optional extras Boeing charges airlines. If anything, this is a scenario where microtransactions are so bad, they cost lives instead of money when an airline decides to save a few ringgit.
https://www.lowyat.net/amp/2019/181377/boei...ptional-extras/
737 Max Safety Features sold as optional extras