In the history of the Chinese aviation industry, some aircraft models are as bright as shooting stars, but fleeting. In 1964, while China was designing the J-8 fighter aircraft, in order to solve the shortcomings of the fighter aircraft's ceiling, poor high-altitude and high-speed performance, no radar, and poor high-altitude mobility, a plan for the design of the J-9 was proposed. At that time, the avant-garde design philosophy of the J-9 greatly surpassed the J-8 plan in terms of design performance, but it also caused a lot of insurmountable difficulties in the development process. China finally chose the gradual modification plan of the J-8 and abandoned the development of the J-9 fighter.
At the beginning of 1965, the Third Machine Ministry held a meeting of leading cadres of enterprises and institutions (ie, the 651 meeting). During the meeting, Vice Minister Duan Zijun chaired a seminar on the development of new machines. The meeting requested that the Sixth Institute and the First Institute should demonstrate the plan of the J-9 aircraft with 10% technical force. Participants at the time did not expect that the fate of the J-9 was so horrible; nor did they necessarily think of the development of the J-9, which preliminarily prepared for the rise of the 611 Institute and the development of the J-10.
The F-9 FANTAN designation was at one time applied to the Q-5 FANTAN attack aircraft. Should the FC-1 enter PLAAF service, it might carry the J-9 designation.
The design dates from the 1970s, and it could have been an impressive aircraft, for the time, had the required technology been available. The J-9's performance requirements were focused on beating the F-4 Phantom II in combat, which had emerged as the primary American fighter aircraft in Vietnam. It was intended to carry the the PL-4, the PLAAF's version of the Sparrow, which had an SARH and IR versions. This missile was cancelled in 1985 due to technical issues. Development of the J-9 was halted in 1980 in the wake of the inability to develop the high-performance engine needed for the aircraft. The Shenyang J-8 Finback and its developments ended up filling the role intended for the J-9 design. While the J-9 remained unbuilt, it laid the ground for Chengdu's later development of the J-10 fighter, which was also a canard delta planform.
The J-9 designation was apparently initially applied to an unbuilt single engine development of the J-8 aircraft that was cancelled in development around 1979. The J-9 plan that China began to study in the late 1960s involved a duck layout, but the main research direction of the J-9 was still on the tailless delta wing. In the mid and late 1970s, it was found that simply adopting the tailless delta wing could not solve the J-9 equirements. Performance indicators before focusing on the duck layout with fixed front wings. The layout of the newly built 611 accumulated at least 5 different models and no less than 2,000 blow and free-fly model studies.
It should be noted that the main wing of the J-9 series fighter was adjusted several times. The early J-9 fighter was greatly influenced by the design of the US-made F-4 fighter, and its main wing shape was very similar to that of the US-made F-4 fighter. Later, in order to meet the requirements of the "Double 25" indicator, it was changed to a triangular wing design similar to the French "Mirage" series of fighters.
Nikolai Cherikov ["The Shenyang F-9 Combat Aircraft" Interavia, vol. 31, Dec. 1976, pp. 1160-1162] reported that China began the development of its own combat aircraft, designated the F-9, after the final break with the Soviet Union at the beginning of the 1960s. The design of the F-9 was largely based on that of the Soviet MiG-19, which had been constructed in China under license. The F-9 was to be given an all-weather capability. Various modifications were made to improve aircraft performance and enhance its operational life. The development of the F-9 from the MiG-19 was viewed as an interim solution.
The J-9, built by Chengdu Aircraft Corporation, never entered production. The single engine, delta canard design was cancelled in 1980, but the aerodynamic research in the program paved the way for the J-10 and J-20. Following early aerial combat over Vietnam in 1962-63, the PLAAF recognized that the range and performance at higher altitude of the J-6 and J-7 fighters [MiG-19 and MiG-21] were inadequate to counter American fighters. In October 1964 the development of a new fighter was initiated. Concept studies were initially based on evaluation of simulated dogfights using the J-7, which had a low combat radius, poor intercept speed, inadequate fire control radar, and dated aerodynamic characteristics.
The 601 Bureau in Shenyang began work on improving the J-7, with two possible development paths pursued in parallel:
- The use of the J-7 as basis for an advanced twin-engined jet fighter. The general layout of the standard J-7 was to be retained without major changes. It would be powered by two improved versions of the WP-7 turbojet with thrust of 43-44 kN (4.4 klbst) each. This approach eventually led to the Shenyang J-8.
- The development of a new single-engined fighter using a new turbofan engine (which was to be designed by the 606 Bureau) in the thrust class of 83-121 kN (8.5-12.4 klbst) with a new air intake configured to accommodate a suitable radar. The primary challenge with the second approach was China's lack of experience with a modern turbofan engine. Consequently, many engineers associated with this approach feared the development of the engine would hold back the development of the fighter, whichw as in fact what happened.
The initial goal of this two-fold development program was a an air superiority fighter in the 10-ton weight class with an operating altitude of 22,000 meters, a maximum speed of Mach 2.2 with a range of 1.600 km, in order to keep up with the performance of the American F-4 Phantom II. These goals were later expanded to "2 x 25" - Mach 2.5 at 25.000 meters.
In 1964, Shenyang Aircraft Design Institute, that is, 601, proposed two improvements based on the J-7 fighter at a conference. This was the later J-8 fighter and J-9 fighter plan.
The J-8 program was also called the "Mig-21 Gradual Modification" at that time. From the name, it can be seen that this is a relatively conservative plan, which directly uses the design of the original MiG-21 fighter aircraft. Improved turbojet 7 engine, while lengthening and enlarging the overall fuselage to accommodate more on-board fuel and aviation equipment.
The J-9 plan is called the "Mig-21 Major Modification Plan". This plan uses air inlets on both sides to free up valuable nose space for the installation of airborne radar. At the same time, the turbofan-6 engine designed by Shenyang Engine Design Institute, that is, 606, was used instead of the turbojet-7 engine.
On October 25, 1964, 601 proposed two variants of the J-7 variant. One scheme is a double-type, with a modified version of the turbojet-7 engine used by two J-7s. The aerodynamic layout of the aircraft is referenced to the J-7 without major changes. This scheme was later developed into the J-8; This scheme is a single type, and it is proposed to install an afterburning turbofan engine with a thrust of 8500kg, that is, the J-9 scheme. In 1966, the three aircraft department reported the design of the J-9, and proposed a maximum speed of Mach 2.4, a ceiling of 20,000 meters to 21,000 meters, a maximum range of 3,000 kilometers, a combat radius of 600 kilometers, a battery life of 3 hours, and a climb rate of 180 to 200 meters. /second.
The 601 first selected 4 types of wing plane shapes, that is, the leading edge swept 50 degrees, swept backwards, the leading edge swept 57 degrees, and the leading edge swept 55 degrees, and the double leading edge swept angles. Double delta wing and designed a wind tunnel model. The main consideration is to use swept-wing or delta-wing. Both the swept-wing and delta-wing use the leading-edge swept method to increase the critical Mach number of the wing. However, if the supersonic flight is increased to Mach number 2.0, the subsonic sweep-back scheme must be used to make the leading-edge sweep angle greater than 60 degrees. However, if the leading-edge sweep angle is too large, the force on the wing root structure will deteriorate. In addition, the aerodynamic characteristics will also deteriorate at low speeds, the lift will decrease, and the drag will increase, which will directly affect the maneuverability of the fighter. Therefore, it is disadvantageous to use large swept wings. The delta wing is more suitable. It not only has the advantages of the swept wing, but also the longer wing root chord length ensures the root structure stress condition, reduces the structural weight, and also helps to ensure the aircraft's longitudinal flight stability. Therefore, the first three schemes were eliminated by 601, and the leading edge sweep angle of the delta wing was changed to 55 degrees, which is called the J-9IV scheme.
However, from the fourth quarter of 1966 to the beginning of 1967, after wind tunnel experiments, it was found that the mobility of the J-9IV scheme was not ideal, so a tailless delta wing scheme, the V scheme, was proposed.
The Cultural Revolution stalled Chinas development of its military aviation considerably, affecting both the J-9 program and the accompanying PL-4 program. Difficulties producing the WS-6 engine in particular made development of the aircraft extremely difficult. The J-9s specifications were in many ways comparable to a fourth generation fighter, and many of the fighters characteristics were adopted onto the later J-10 single engine fighter program.
NEWSLETTER |
| Join the GlobalSecurity.org mailing list |
