https://phys.org/news/2019-03-boeing-airlines-tough-path-max.html > The US on Wednesday grounded the 737 MAX 8 and MAX 9 models while it continues the search for the cause of the crash, which happened less than five months after a Lion Air plane of the same model went down in Indonesia, killing 189. > Both accidents occurred a few minutes after take-off, a similarity that led authorities around the world to pull the plane out of operation.