Typically, this rank is not achieved before at least 20 years in the service.
There have been about 180 generals in the history of the U.S. Air Force. They are usually pilots, and they are responsible for major commands.
The Air Force comprises nine major commands, organized by their function within the United States and overseas, and structured to accomplish specific Air Force goals such as air combat; space and intercontinental ballistic missile operations; and research and development of weapons systems.
To get an idea of the far-ranging responsibilities generals embrace, consider the job held by the first officer to be awarded the rank of general in the U.S. Air Force in 2007. Gen. Victor E. Renuart Jr. presides over the U.S. Northern Command, which was created in the aftermath of the Sept. 11 terrorist attacks to protect the United States. As commander, Renuart is responsible for U.S. military operations in the continental United States, Canada, Mexico and the northern Caribbean. He oversees 1,200 uniformed and civilian members of all branches of the U.S. military.
Promotions occur as vacancies open up within the ranks of commissioned officers. Boards composed of senior officers determine which candidates are promoted based on their service records. The Secretary of Defense convenes the selection boards every year to make decisions for ranks higher than O-2 (first lieutenant). Most senior officer promotions also require confirmation by the U.S. Senate.
In addition to achievement, promotions are based on the number of years of service and how many positions are open in each pay grade.
There were only 12 active-duty generals in the U.S. Air Force in September 2005. Fewer than 0.5 percent of commissioned officers make it to the top three ranks -- major general, lieutenant general and general.
The president nominates officers for the rank of general, and the U.S. Senate must confirm the appointment. When a general retires or loses the rank for some other reason, the president suggests a replacement to be promoted from a list of nominees. The mandatory retirement age is 62, but it can be pushed to 64 in some cases.
Generals can be demoted. Consider the case of John Daniel Lavelle. In 1972, he was relieved of his duties only a year into his service as Seventh Air Force commander, responsible for all Air Force combat air strike, air support and air defense operations in mainland Southeast Asia, amid a controversy over his command style in Vietnam. An inquiry later found that he had ordered the bombing of unauthorized North Vietnamese targets.