First solo flight
The first solo flight is when a new airplane  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). Requirements 
Depending on the country, there may be a requirement for some minimum number of training hours to have been completed by the student pilot before they are allowed to solo. In most countries, it is assumed that such students will be familiar with (and may have to pass an examination on) the relevant air laws or regulations, and will have completed exercises in handling aircraft in normal conditions, and also what to do in the case of engine failure on takeoff, in flight, and before landing. In the United States, for most aircraft, there is no FAA (Federal Aviation Administration) requirement for a minimum number of hours, but a student pilot certificate is required. Per FAR Part 61 SFAR 73 section 2, Robinson helicopters have a 20-hour requirement to solo. However, the regulations do require that a student pilot show competency in several specific skills to include, for example, the ability to forward slip. In practice, competence is mostly a judgment call of the Certificated Flight Instructor (CFI) responsible for the student. Typically, it takes from 10 to 30 hours of flight time before a pilot has the instinctive feel of an aircraft to be safe flying solo in other than perfect (no wind) weather. Soloing 
In some cases, when the student is given permission to fly alone, the instructor directs the student to fly three circuits of the traffic pattern, each accompanied by a full-stop landing. During the first circuit, the solo, the student's flight instructor may supervise the student's performance from the ground, paying close attention to the approach and landing. Some instructors keep a radio handy, if there is one in the aircraft, in case the student pilot should need assistance or advice. When flying a glider the newly approved student may also make more than one tow the first day, though a single solo flight is adequate to earn the "A" badge as a glider pilot. Traditions 

Various traditions or rites of passage have developed around "soloing", including drenching the student with water, or cutting off the back of their shirt. External links
 Langley Flying School "Flying on your own!" Phoenix Aviation "What happens on a student's first solo"

References 

Flight training
Rites of passage