Pre-2008 you could get unsecured loans for flight training, but they don't do that any more.

You'd need security or a co-signer today.

For a university degree program, you should be able to get a regular student loan, but I suspect that would only be for the academics, not the flight training. You will need a degree anyway if you don't already have one.

The military GI bill will pay for flight training, you would obviously need to serve but not necessarily as an officer.