It's like if you replaced your 2015 car with a new, but heavier 2020 model. Since its heavier, but has the same braking system as the 2015 model, it has a longe

It's like if you replaced your 2015 car with a new, but heavier 2020 model. Since its heavier, but has the same braking system as the 2015 model, it has a longer braking distance. To remedy that the engineers put in a "braking characteristics augmentation system" (BCAS) to augment the braking power applied, so that it stops sooner than a person normally would. It uses a single camera and computer vision to detect obstacles ahead. The car company didn't think they need to tell its drivers about it. One day you'll be driving and all of a sudden come to a screeching halt (and maybe cause a wreck) and come to find out the camera was obscured by a precise strike of bird poop. The car company could have either A) told and trained their drivers at the dealership to brake harder than normal, B) used a two-camera backup system, or C) redesigned the brakes to accommodate for the increased vehicle weight. MCAS is basically that. It makes the MAX8 maneuver and behave just like the previous 737 models, even though the larger engine and more forward placement causes it to fly somewhat differently in certain situations. The failures came from the lack of training and understanding of the system as well as a flawed implementation using input from only a single sensor instead of two. Without MCAS, they would have required a significant amount of training and possibly re certification, which costs at least a few billion dollars more than a few hundred lines of code (but unfortunately a lot less than 346 people's lives and many many billions of dollars of follow-on debt).