A couple of days after filling out the online form (which was very simple and straight fowrard) I received a call from the graduate recruitment office. This lasted about 15 minutes and went over some basic questions such as why I wanted to work for BAE systems and what I knew about the company. The recruiter then explained a bit about the roll that I was applying for and the specific route that I wanted to take.
2 days later I recieved another call from the recruiter asking me if I wanted to go for an interview. I accepted.
This first interview was mainly competency based, there were a few awkward questions, such as "describe a time you were given negative feedback, how did you overcome this", but mostly it was pretty standard competency questions. The interviewer then explain a little bit about their job and answered any questions I had. The next part of this interview consisted of a case study. This is generally a simple mathematical problem. Then there were some general HR questions and the interview ended.
Within a week I was called by the graduate recruitment office. They asked me how I thought the interview went and then went on to giving me specific feedback. After that I was invited to a second round interview. I was told that I would have to prepare a presentation on "a complex problem". This was a very vague description but it did give me the freedom to prepare anything I liked. I would recommend not using anything that involved reallly complicated maths or you could risk losing the interviewer and to keep it light hearted an upbeat.
The second round interview was a lot more in depth. It started with me giving my presentation, after this I was asked questions surrounding the topic that I gave, so make sure you know the general are you are presenting in very well. Next we went through my CV and was asked questions on that. The final part of the interview consisted of a few more case studies similar to what was given before. One was particularly tricky but getting part way through it seemed to be enough so don't be disheartened if you can't get to the final answer on all of them.
Within a week again I was called up by graduate recruitment offering me the job!