Googling- "CNC Programmer aerospace salary", looks like about $53k/year, does that sound right?
Don't be in too big of a rush to live that stable adult house-owning life. Your 20's (and you're not even there yet!) are a great time to invest in yourself, building up to long-term payoffs. Better yourself, decide what your resume to look like in 10 years and make it happen. Aim big, BIG!
Your middle paragraph- I really think you should be looking to invest in yourself & build yourself, and whatever opportunities you have through the family business, that's just a nice bonus.
If you could get into a top CS program, you could be earning $200k/year after 4 years. Add it up over a 30+ year career. Or go do a startup, start your own business, it could be something that synergizes with your dad's so if/when you hit that inheritance you'll just have a bigger empire.
I studied CS at UW in Seattle and some of my peers worked part-time at Boeing during the school year with full-time internships in the summers, it works out splendidly, sounds like you've got a similar option, being a family business you should be able to contribute part-time no problem. 4 years is nothing in the long run.
My words are unlikely to sway you now, just some things to consider. Cheers.