we want". On 18 December 2013, production of Block 2 JF-17s began at PAC's Kamra facility. These have an air-to-air refuelling capability, improved avionics, enhanced load carrying capacity, data link, and electronic warfare capabilities. Block 2 construction is planned to run until 2016, after which the manufacturing of further developed Block III aircraft is planned. In December 2015, it was announced that the 16th Block II aircraft had been handed over resulting in standing up of the 4th squadron. On 17 June 2015, Jane's Defence Weekly confirmed that JF-17 Block III will have an AESA radar, a helmet-mounted display (HMD) and possibly an internal infrared search and tracking (IRST) system. A two-seat version was also reportedly be produced in Block III. Unconfirmed reports claim that Block III will also have a better flight management system. Selex ES has promoted its next-generation cockpit as a possible upgrade of JF-17 Block III; this cockpit includes a new mission computer, an enhanced head-up display and contemporary multi-function displays, plus the capability for the pilot to use a single, large-area display instead. In July 2020, despite Indian protest Russian state-owned United Engine Corporation developed a new engine RD-93MA for JF-17 fighter being built by Pakistan. Design Airframe The airframe is of semi-monocoque structure constructed primarily of aluminum alloys. High-strength steel and titanium alloys are partially adopted in some critical areas. The airframe is designed for a service life of 4,000 flight hours or 25 years, the first overhaul being due at 1,200 flight hours. Block 2 JF-17s incorporate greater use of composite materials in the airframe to reduce weight. The retractable undercarriage has a tricycle arrangement with a single steerable nose-wheel and two main undercarriages. The hydraulic brakes have an automatic anti-skid system. The position and shape of the inlets is designed to give the required airflow to the jet engine during maneuvers involving high angles of attack. The mid-mounted wings are of cropped-delta configuration. Near the wing root are the LERX, which generate a vortex that provides extra lift to the wing at high angles of attack encountered during combat maneuvers. A conventional tri-plane empennage arrangement is incorporated, with all-moving stabilators, single vertical stabiliser, rudder, and twin ventral fins. The flight control system (FCS) comprises conventional controls with stability augmentation in the yaw and roll axis and a digital fly-by-wire (FBW) system in the pitch axis. The leading-edge slats/flaps and Trailing edge flaps