Initially failed the online assessments (numerical and verbal reasoning) but was emailed a week later to say I was still being considered. Then involved an on-line interview answering pre-recorded strengths based questions. The assessment center was very relaxed with an overnight stay in a hotel (room and meals paid for by BAE). The day itself involved a one-to-one interview with someone from the business unit you applied to, and was mainly strengths based with some general technical questions. There was also a written exercise, group exercise, and a presentation. We were given the topic and 15 minutes to prepare a 10 minute presentation on it to two of the assessors.