Some good questions to ask are:
When you all went through training, what were the harder subjects?
If I work hard and keep my nose clean, what sort of progression path is possible?
Ask about retirement, benefits, and/or how they balance work/life with family. It shows your long-term view and that you think responsibly. Also, have a reason why you want to work there that is not attached to money or your last job being bad and ties you to them for the long-term.
Rephrase the 1st to asking about their path. It gets them talking about themselves (which is always a good thing) and it takes the possible inadequacy light from possibly shining your direction. The classes are tough in some areas, so what? It's not like knowing that now is gonna make you turn down the job...
I disagree the 2nd question...You should already go into the interview knowing the progression path. It does get a little muddled at the top after you do SRO, but you should know what it takes to make SRO.
They specifically asked me, "Do you want to advance and take leadership? Do you think you are able to be an SRO in 3 years?"
SRO is their sweet honey spot that they have problems getting people qualified for and/or keeping. Once you get SRO (if you can handle it) you can move to any job and any plant and be a hot commodity. Even if you stay there, every department wants a piece of you (training, supv, supt, etc.) which some have to go which leaves them still needing SRO's.
There is so much more to post, but I will leave it at that.
Good luck on your interview.