[Trippynet]

If I recall, the fixes were actually to add additional kevlar linings to the tanks.

Regarding the 737 Max, my biggest issue with it is that MCAS relies on data from a single sensor (with two fitted to the plane) - meaning no redundancy for the system. Boeing have been talking for a while now about a "software update", but this cannot properly address the issue. The Max should have 3 sensors minimum, with onboard software capable of "voting out" one of those sensors if its readings disagree with the other two. That is how critical systems should be implemented if safety (rather than profit) is the primary concern.

Boeing may be looking to modify the software to allow for readings from both current sensors, but in the event of a sensor problem it still doesn't answer the question of which sensor is at fault? In short, it's a bodge and no matter what they do software wise, the plane will still have a weakness due to only two AOA sensors being fitted.