I applied as a part of the EAHI program. It is only one interview and if you get it, then Boeing gives you a letter of intent (equivalent to a job offer). The questions are based on the STAR Method and are purely behavioral. The interview is very basic and not difficult, but the EAHI program is very picky since they are literally just hiring based on a single interview. Only 5 questions aside from the initial introduction were asked. The worst part is the people who interview you. They are very nice but spend the entire time just writing down answers/notes. No interaction whatsoever; not even a smile. I felt like I was talking to scribes for an hour.

HR interview checking if you are somewhat qualified - not too hard. Than interview with hiring manager and lead engineer to see your skills, experience, and fit for team - average difficulty.