Joint production with the Chinese Air Force of a light-weight multi-role combat aircraft and further avionics development of the JF-17 is ongoing at the Pakistan Aeronautical Complex (PAC). As of 2016, 70 JF-17s are operational and have replaced 50 Mirage IIIs and F-7Ps. The PAF plans to replace all F-7Ps and Mirage III/5 aircraft by 2020. The F-7PG will be replaced later, and the JF-17 fleet may eventually be expanded to 300 aircraft. Realizing the importance of fifth generation fighter aircraft, the PAF successfully negotiated for the procurement of approximately 36 Chinese FC-20 fighter jets – a deal worth around US$1.4 billion, signed in 2009. It was expected that the FC-20s would be delivered in 2015. In close co-ordination with Turkish Aerospace Industries, the PAC engaged in a mid-life update (MLU) program of its F-16A/Bs, approximately 26 of which are in service. In 2010, the air force procured at least 18 newly built F-16C/D Block 52s under the Peace Gate-II by the United States.