I applied online in April and waited a lonnng time until I got a response (~3 months). When they did contact me, I spoke to someone on the phone from HR who coordinated and set up a phone interview. I guess they primarily do phone interviews now as a cost saver, and will only bring you in if you live nearby. Once I set a date/time for the interview, they emailed me a .pdf describing the format. It is a "structured interview" (a standardized process they use on all applicants) consisting of several behavioral questions, and the answers are scored by the interviewers during/afterwards.
So, naturally I was totally freaked out. The .pdf noted that you HAD to answer each question in a particular manner: a thorough description of the Situation, Actions taken, and Results of the actions [SAR or STAR method]. You were reminded of this at the beginning of the phone call by the interview panel and sometime in the middle of the interview. Make sure that you use your own experiences and answer the questions in the format that they want. If you do not, then your score will suffer.
I thought that I totally blew the phone interview, but a few weeks later I got another call from the same HR contact saying that they wanted to bring me in for a site visit. The visit was an all-day event and I was moved around from manager to manager at the site having short ~30-45 minute conversations with each one. My impression was that they already decided to offer the job to me but just wanted to 1) see if I was a crazy person, 2) give me a chance to see if this site was a good fit for me. As a sidenote, they paid for travel and housing. At the end of the day the main manager in the process said that everything went really well and that I should expect a final decision soon. A few days later, I received another call from the manager, and he said that they were offering me the position and that I could accept/reject it on my Boeing career site.
TLDR: You have to be patient; From when I applied to when I started it was almost 7 months. Also, in the interview, just follow the instructions and try to stay calm. If you get a site visit, that is when you can totally crush it and prove how good you are for the position!