The aerospace industry does not write complete and correct code. Hate to terrify you, but it's true. Some companies do, some specific areas do. Most are just a

The aerospace industry does not write complete and correct code. Hate to terrify you, but it's true. Some companies do, some specific areas do. Most are just a step or two above the software industry average in terms of quality, which is not that stellar. They don't get there by using a lot of formal methods or thinking deeply. They get there by testing the shit out of everything and static analysis tools (which have gotten a ton better since I started in the industry). Some of the programmers I've had to clean up after were mediocre, at best (though others were stellar). The main reason their systems don't kill people is the testers standing between you and their original code. MBSE has been picking up, and it's a good thing. It's not as big as it should be or always used effectively, but it's helping.