Apart from usual SW tests, Lots of testing with airlines and experienced pilots. Processing feedback and improving the model step by step over the course of several years.
I'm very curious how you "bootstrap" a model like that. Do you start with a physics simulation? Make an educated guess and then get pilots to label when it's wrong in order to incrementally improve? Recruit pilots to manually track CAT events?
I've had to build a few of these kinds of models over the years, and it's consistently the hardest task I've faced in my DS career.
The second is closer to reality , initially let pilots (lots of them) label flight events and after landing take all data and build the algorithm around their initial labels. The when there are more pilots let them label agree / disagree and relabel etc.
Another aspect is you have usually two iPads in the cockpit for captain and first officer so you can correlate and match what both accelerometers read.
I've had to build a few of these kinds of models over the years, and it's consistently the hardest task I've faced in my DS career.