To start the interview they initially contacted me to find out if I was still interested and then to ask when the best day for me to do the interview would be. They then made travel arrangements for me to fly to the location from Oregon. When I arrived at the location I was assigned a guide, partially because it was a restricted area and partially so that I could talk with him and learn a bit more about the position and the responsibilities. When it came time for the interview, it was a panel of 3 managers from separate operations, one of which was the manager that I would be working under. Overall it was a fairly standard interview, with the basic questions everyone asks, including but not limited to what my favorite class was, where I'd see myself in 5 years and the like. Afterwards I thanked them, they thanked me and that was about it.
The people who were there were fairly relaxed and seemed friendly. The only reason I put the experience as neutral rather than positive was because afterwards there was no contact whatsoever as to if I had an offer or if I was rejected.