As an intern you do a bunch of busy work. Basically all the paper work between the designs the actual engineers don't want to do, that are necessary for any changes or proposals to happen within an defense/gov contracted company. Even if you do get to do some things a little more interesting like CAD, it's all very insignificant work like modelling bolts or circuit chips. Lots of times there isnt work for you to do, and time is wasted. This however, is typical of many defense companies, not just for interns but for entry level engineers as well. Large government contractors are stable and pay well, but they are so compartmentalized that you end up doing the same work day after day. Good pay, but boring: a trade off between being in a larger company with money and smaller company with more things that need to be done.