According to foreign media reports, the UK has recently launched a flight test program aimed at testing the avionics system of its sixth generation fighter jet, the Tempest. For this purpose, the UK Ministry of Defence has selected Leonardo and 2Excel to jointly undertake the modification task of a Boeing 757 aircraft, which will be named the Excalibur flight test aircraft. It has a maximum payload of 16 tons and can fly at a speed of 0.86 Mach at an altitude of 12000 meters, with a maximum range of over 7200 kilometers and a range of 8 hours. The first phase of the modification of the "Divine Sword" flight test aircraft has been completed, including the installation of fairings on the side and front abdomen of the fuselage to evaluate the stability of aviation electronic equipment during flight. The future plan is to install fighter style nose cones at the nose of the aircraft to test the radar system of the "Storm" fighter jet. According to the rendering released by 2Excel company, the flight test aircraft will be equipped with additional fairings below and on both sides of the nose, and two fairings will be added to the rear abdomen. The fairings below the nose are mainly used for flight testing of photoelectric sensors. It has become a common practice to use civilian aircraft for testing aviation electronic equipment and engine components of military aircraft. The United States once modified a Boeing 757 aircraft as a flight test plane to test the radar, sensors, and electronic warfare kits of the F-22 fighter jet. The flight test aircraft is equipped with the nose of the F-22 fighter jet and is equipped with an AN/APG-77 active electronic scanning array radar. A pair of swept wings are also installed on the top of the nose, specifically for testing the conformal antenna of the AN/ALR-94 airborne radar warning system. The modification of passenger aircraft for testing military aircraft avionics equipment has multiple advantages. Firstly, the large fuel capacity and long endurance of the aircraft can support long-term flight testing and enable repeated testing tasks, which helps to identify and troubleshoot technical issues. Secondly, compared to fighter jets, passenger planes have larger space and can carry more testing equipment and technicians, greatly improving testing efficiency. Once again, considering fuel economy in the design of the aircraft, the flight cost is lower, which helps to reduce overall testing costs. The Boeing 757, as a medium-sized single aisle narrow body aircraft, has not only been selected as a flight testing platform by the UK, but also frequently used by the US for testing aviation electronic equipment and related tasks. This is mainly because the total production of this aircraft model has reached 1050, and it has been discontinued and retired from multiple airlines, resulting in relatively low procurement costs. At the same time, the Boeing 757 places special emphasis on reducing operating costs and improving fuel economy in its design. Converting it into a flight test aircraft can help reduce testing costs. In addition, as a mid size aircraft, the Boeing 757 not only avoids the drawbacks of short endurance and difficulty in supporting long-term testing for regional aircraft, but also overcomes the problem of high operating costs caused by various indicators exceeding necessary requirements for remote aircraft, achieving a good balance between performance and cost. The report states that other parts of the current "Storm" fighter jet project are also steadily advancing. The demonstration aircraft is being manufactured at BAE Systems' factory in Walton, northern England, and the accompanying engine is undergoing aerodynamic testing at Rolls Royce in the UK. However, the project still faces some difficulties. Against the backdrop of budget cuts by the UK Ministry of Defence, the budget for the 'Storm' fighter jet project may be squeezed. In addition, developing a new fighter jet will inevitably face design challenges, as well as long development cycles and high costs. (New Society)