United's application and selection process for flight officers involves three phases. In the initial phase, United accepts applications from individuals meeting certain minimum qualifications including 350 hours of flight experience, commercial pilot certification, a high school diploma, and other physical and medical requirements. United then ranks eligible applicants according to aeronautical experience. Those applicants ranked at the top of the list advance to the second phase of the selection process. Because female applicants typically have less aeronautical experience than male applicants, United ranks male and female applicants separately. United then selects a proportionate number of males and females to proceed to the second phase. At the second phase, applicants must complete a simulator flight and a formal interview. Based on the applicant's performance, a review board then decides whether to reject the applicant or to extend a conditional offer. If United extends a conditional offer, the candidate moves on to the third phase, which includes a medical exam and background check.