“This ACARS pings come ONLY if there is something mechanically wrong to notify ground crews of what needs repair”
I think that depends if they are also using it for trend monitoring. In that case there are many exceedences that will also cause it to ping. If for example the aircraft were hijacked and put into a steep dive, several allowed engine parameters could have been exceeded. Likewise flying too fast too low to the ground would as well.
Don’t play by the rules and them engine manufacturers are going to make sure your power by the hour cost increases!
My point is simply that ACARS is NOT a black box mime and has NEVER been one. It is NOT a continuous feed. A steep dive may or may not cause it to ping.
The way the WSJ article was written implied that this is a continuous data stream which it is not.