I don't have any experience on this field, but researching the subject some time ago I found that C/C++ is not unusual too. On the safety matter, when used in critical mission systems they usually follow a guideline or framework to ensure the reliability of the software, like MISRA C[0] for exemple. Another important point is that the development is real slow compared to other segments of software engineering and often takes several years to develop, with lots of tests and rigorous compliance with specifications.

Its an interesting field, but feels hard to get into.

[0] https://en.wikipedia.org/wiki/MISRA_C

From what I understand, the vast bulk of the onboard F-35 software is written in C++.

One wonders how much that's contributed to the lengthy delays in software delivery...

Regardless, it seems possible to eventually produce effective software using C++. ;-)