A number of Afghan pilots and pilot-candidates traveled to the United States beginning in May 2009 for English language training, to be followed by instrument training for the pilots and undergraduate pilot training for the pilot-candidates. This was the start of an initiative that within the next several years should produce a small cadre of seasoned, instrument-rated Afghan Air Force pilots as well as a larger number of younger, well-trained pilots who will serve as the backbone of the Afghan Air Force for the next generation. Other NATC-A-led programs include English language and technical courses for AAF personnel in various specialties including aircraft maintenance, logistics, communications, and engineering. As of June 2009, the Air Force numbered about 2,400 airmen, with a planned strength of 7,400 airmen within several years.