The first solo flight is when a new aircraft pilot completes a takeoff, and usually a short flight and safe landing, by themselves. Flying such a flight is a milestone known as soloing. Being solo pilot of an aircraft is different from most other situations in that the pilot has not only to be able to fly and navigate the machine in a competent manner but they also have to be able to cope with unpredictable developments like mechanical failure, bad weather etc. on their own and without advice from other sources (most air traffic controllers are not pilots and may not be contactable anyway).