The Ukrainian Air Force () is the air force of Ukraine and one of the five branches of the Armed Forces of Ukraine. Its headquarters are in the city of Vinnytsia. When the Soviet Union dissolved in 1991, many aircraft were left in Ukrainian territory. Ever since, the Ukrainian Air Force has been downsizing and upgrading its forces. The main inventory of the air force still consists of Soviet-made aircraft. As of 2007, 36,300 personnel and 225 aircraft were in service in the Ukrainian Air Force and Air Defense forces. Since Ukrainian independence in 1991, the air force has suffered from chronic underinvestment, leading to the bulk of its inventory becoming mothballed or otherwise inoperable. Despite this, Ukraine still possesses the world's 27th largest air force and the seventh largest air force in Europe, largely due to the ability of its domestic defense industry Ukroboronprom and its Antonov subsidiary to maintain its older aircraft. The Ukrainian Air Force participated in the war in Donbas. Following the 5 September 2014 ceasefire, the air force was suspended from carrying out missions in the contested areas of Donbas. Since February 2022, the Air Force has been engaged in constant combat operations in the face of the 2022 Russian invasion of Ukraine. Missions The role of the Air Force is to protect the air space of Ukraine. The objectives are: obtaining operational air superiority, delivering air strikes against enemy units and facilities, covering troops against enemy air strikes, providing air support to Ukrainian Ground Forces and the Navy, disrupting enemy military and state management, disrupting enemy communications, and providing air support by reconnaissance, air drops, and troops and cargo transportation. In peace-time, this is carried out by flying air-space control missions over the entire territory of Ukraine (603,700 square km), and by preventing air space intrusion along the aerial borders (totaling almost 7,000 km, including 5,600 km of land and 1,400 km of sea). Over 2,200 service personnel and civilian employees of the Air Force, employing 400 items of weapons and equipment, are summoned daily to perform defense duties. On average, the Ukrainian radar forces detect and track more than 1,000 targets daily. As a result, in 2006 two illegal crossings of the state border were prevented and 28 violations of Ukrainian air space were prevented. Due to such increased strengthening of air space control, the number of air space violations decreased by 35%