Who designs things such as tanks and fighter jets, are they employed by the military or are most tanks and fighter jets built by private companies.
It comes from multiple sources. Just because a certain company makes a tank, or what ever doesn't mean they made every component on the tank. Often many supplier will produce the same equipment if the needs are great.
The engineers that work at the respective military contracting companies that send contract bids to the government in the hopes of having their product become a piece of military hardware (or software). Companies like General Electric, FMC Corp., Northrup-Grumman, etc.
