How to get into big machines?  

Cool calm thinking and forward looking on the job responsible do it yourself and coordinate with all types definitely have a place in any operation. 

The "I've got 15 years in the military" begs "why not 20?", what's the beef, get kicked out, couldn't hack it, got offended?  As offensive as all that drivel in itself sounds those are the thoughts that go through management heads IF you were to approach them with "I've got 15 years in the military, wind me up and watch me walk".

If you're moving on from the military don't look back unless it is a Reserve/NG unit and definitely embrace learning how to walk and talk in the civil environment cuz it is definitely one where you will shoulder as many responsiblities as your employer chooses to throw at you. 

It is usually just a challenge to "get the job done safely" and fun with the right attitude.