I interviewed for 4 spots in the ship signatures department (acoustics). It's a long day but it was managed pretty well so even by the end I wasn't excessively tired. All of the interviewers I met were pretty down to earth and didn't ask any impossible questions. Although it said it was an 8 am start it didn't really start until 8:50 but being there early is always a plus. After a tour of the Groton side you go back to the employment office and get put on a shuttle to go to the New London side. This is where almost all of the engineering work is done now and also where all of my interviews were held. You get an escort to the room and all of the interviews came to me so there is no hope of getting lost. The last interview took place while having a paid for lunch in the cafeteria. The food was pretty good. Dress code at EB is pretty lax and keep in mind there is a decent amount of walking outside but I wouldn't want to interview in anything less than formal attire. All in all I would say it was a relaxing day (comparatively) and that as long as you bring your things with you that there is nothing to worry about. Keep in mind that you may not know if you have the position for several weeks after the interview (3-4 in my case so they say).

Just one interview around 30-45 minutes. Fairly simple and straight forward. After you apply, they email you to schedule an interview. Usually it's with a few people or a panel. Easy questions about yourself and broad technical questions about your experience.