[tacticalDonut]

US DoD heavily controls what can and can't be installed on their stuff. To make matters worse each branch and organization has their own approach to how they control what gets installed.

Sometimes it's just the path of least resistance to use what you already have.

I remember putting in a request to install Python. It took me 6 months to get a response of no. I had the opportunity to appeal with more information on the use case, but I just did it in VB for Excel at that point.

[ghc]

While that's true, FTEs (Flight Test Engineers) tend to have more leeway. As I said above, I've seen Army S6 give approvals for all sorts of programming environments. And the AFTCs seem to be a bit more lenient than that even when it comes to deploying in SCI environments.

Granted, I've also seen a piece of software denied because it has USB in the name (even though it had nothing to do with USB), so YMMV.