A Light Sabre for the Third World: The FC-1 / JF-17 Thunder (II)
Finer Salients
According to the JF-17's engineers at Chengdu, the JF-17 has the world's second combat aircraft to have DSI intakes. These intakes reduce weight, costs and complexity while improving performance. The intake reduces one of the three major forward scatters of an aircraft that typically represents between 30%-35% of the RCS of an aircraft. While the JF-17 began with a similar wing design concept to the F-16, The JF-17 has incorporated a leading-edge root extension that is similar in concept to the F/A-18. The leading-edge root extension (LERX) covers an area of about 9% of the Wing area. This has led to an improved Center of Gravity (CG) and better harmonization of its multirole capability by taking advantage of the pitch digital fly-by-wire Flight Control Systems (FCS) and the variations possible with the LERX.
The result of this is to improve control of the aircraft and to lower supersonic drag. Given the low margins on this class of combat aircraft, such improvement represent a significant feat.
The JF-17's Man Machine Interface (MMI), with full Hands On Throttle-And-Stick (HOTAS) and glass cockpit represent a truly 4+ generation in combat aircraft. The aircraft has the capability to perform air defense, interdiction, airfield strike, precision strike, and escort missions. While deep penetrations into Indian airspace may not be in the order of the day, given the close proximity of many Indian airfields and military installations, the JF-17 can play a significant role for the PAF, even in strike, a role sometimes overlooked by analysts. With the latest modifications and the newer version of the RD-93 (or WS-13), the JF-17 will be able to perform at a large radius of action.
In terms of meeting PAF's specifications, the JF-17 has the distinction of exceeding the PAF Air Staff requirements, including (surprisingly), for the attack role.
The Russian RD-93, despite "engineered" controversy by the Indian media, is slated to power at least the initial batches of the JF-17. The RD-93 is to be equiped with advanced crystal blade technology and a Digital Electronic Engine Control (DEEC). Other than improving the engine performance, the DEEC results in carefree handling under a wide range of conditions and at virtually all relevant altitudes.
The JF-17 has been designed from day one for ease of operations and maintainability. One such feature is that of a single point pressure refueling system. This significantly reduces the turn around time, meaning more sorties can be generated, while maintenance intensive Indian aircraft remain grounded. This is furthered by the modular maintenance design of the aircraft. The level of the serviceability and ease of general maintenance is further illustrated by how panels and components are installed at man's height and a full computer-controlled fault diagnosis and analysis system can be relied upon.
JF-17 II: Evolution Continued
The JF-17 is a truly remarkable plane. Starting from the basic designs that Chengdu and the PAF were tinkering with, the Super-7 with basically a MiG-21 with side intakes, it has evolved into a completely different beast. The Internet Military Aviation community was taken by complete surprise, almost shock when the JF-17 came out with a modern cockpit, DSI intakes and previously unseen quality of build.
Yet, when even the most ardent followers of the program had thought that the JF-17 had fully evolved, it has once again surprised all of us in its next evolution. It is likely that this evolution is going to take shape after the second batch. Changes are comprehensive and across the board and include greater range, lower RCS, AESA radar and a new engine with greater TWR (thrust to weight ratio).
The lower RCS is to be reached using new materials, including advanced composites. A new RAM paint is also rumored that is said to be similar to that being used on the F-35. The nose will see comprehensive redesign and is rumored to incorporate a new AESA radar set of Chinese origin. One proposition is that the single tail is replaced with twin-tails similar to the F-35. A new DSI is also projected that will further lower RCS.
The TWR of the engine is projected to increase with the WS-13, which are likely to go into the second batch. The iteration of the WS-13, possibly the "WS-13A" is likely to go into the stealthier JF-17. Another painted scenario is of a further iteration of the RD-93. This will marginally increase the TWR further, which itself will increase the TWR marginally.
However, this increase in the TWR of the engine will be moderated by the increase in the wing size, greater internal fuel and the twin tails, amongst other weight increases. On the other hand, newer materials and over all weight decreasing projects in turn will moderate these weight increases.
The stealthier JF-17 will incorporate a larger wing, improving higher altitude maneuverability. This is a crucial aspect that is increasingly becoming important in BVR combat, where the higher and faster jets can in some form take pot shots at slower and lower BVR platforms. Another aspect of the larger wing will be increased internal fuel carrying capacity. This is addresses one of the areas that the JF-17 is weaker in - range and the ability to stay on station longer.
The nose, vital areas of the cockpit as well as a whole host of other technical areas will be addressed. the nose will in fact be fully redesigned around a new AESA radar and be formated to lower RCS. The DSI design is also being redesigned to better accommodate and optimize higher altitudes and higher speeds. A second generation of the onboard information collection, dissemination and display will be incorporated.
However, thrust vectoring will not be incorporated, neither will be internal carriage of weapons. This planned version may or may not go into production. However, all, most or many of the changes may be incorporated into the third batch of 50 being ordered by Pakistan. My personal opinion is that this prototype is more of a technology demonstrator. Major changes would not be appropriate unless a major export customer is found. I would think however that all the minor changes, as well as a few crucial major ones will be incorporated. This is likely to include the new engine, as well as the larger wings. Stealth features should also be incorporated but major redesign is likely to be avoided for the 3rd batch production models (such as twin tails and new nose). This version will be targeted for export and will not be part of the Chinese arsenal.
Much of this data is based on rumor, informed speculation and some insider sources. I am grateful to the military aviation community on the web, including Pakdef (particularly pshamim) as well as the dozen or so of the top Chinese military forums.
Note: Picture does not necessarily indicate future design.
Pervez Shamim of Pakdef recently adds:
Some more interesting news. We are aware of many of them. But thought that let me share what I heard recently.
We have seen the controversy regarding the JF-17 engines but now this matter is amicably resolved. And as result Pakistan has received the small batch of two (SBP) this year and doubts subsided. Before the end of this year, another six similar fighters are expected to arrive in Pakistan together with arms and the whole system within this month.
According to plan, the first installment of Pakistan produced- JF-17 next year will have air refueling capability with further improvements in the design. The new production JF-17 will be inducted in 2009. By 2015 Pakistan Air Force plans to replace all the A-5C (strong 5 - C), Mirage 3 and 5, and F-7 - P / PG.
In addition, the activities with and by foreign buyers has already started and a number of countries have shown strong interest in the JF-17.
In regards to the engines, Pakistan is not involved in the Sino-Russian RD-93 engine contract, but the Russians have made an oral commitment to Pakistan that it will not stop the transfer of RD-93 engines.
Taking into account the development of engine technology in the next RD-93 may be the new RD-93B replacement. The new engine thrust will have 10% increase. At the same time China is also developing its own aircraft engine and it may actually produce the RD-93B in China and that will ensure the supply of Jf-17 engines in the long run.
My Pakistani sources say that the new engine’s performance is superior to RD-93. More composite material will be added to the Fuselage. JF-17's Thrust-Weight Ratio will increase with increase in thrust.
The new engine will also provide China and Pakistan with advantage and will enable JF-17 to compete directly with the Russian MIG-29OVT
JF-17 in other areas have also been improved. Aerodynamic improvements have increased their mobility, as well as the ability to engage in a variety of tasks. The small batches manufactured JF-17 is likely to represent the ultimate models of aircraft body Design. Particularly noteworthy is the central fuselage of DSI inlet used in the JF-17 has brought some stealth capability. Other improvements include reduced body weight, through redesigned interior more space has been created, an increase of the fuel carrying capacity, and increased range. Aircraft will achieve speed of 1.8 Mach. After the the improved engine, aircraft’s performance will further be enhanced. The new information shows that the current design will be frozen for the next three years before some further changes are introduced.
Other internal changes that are taking place include the introduction of entire telex control and a more advanced electronic equipment. The new batches will include an IRST. The JF-17 has the all-glass cockpit as we already know, and the first 50 JF-17 will be installed with KLJ-10 radar. Pakistan Air Force is very satisfied with the performance of this radar
In fact there is a reason for making the KLJ-10 radar development very important as it will be put into the first batch of JF-17 for launch of SD-10 giving them the BVR capability. Pakistan Air Force has sought this core capability for a long time, and the JF-17 will be able to shoulder the huge air defense burden. Though there has benn some recent talk of Rc-400 and they may be integrated with the 2nd batch production, Pakistan Air Force ultimately will choose a more advanced AESA radar and the negotiation are already underway with Western suppliers unless China who has been working to develop one can come up with the AESA soon. PAF has not made a decision yet, but it is believed that with the second batch of JF-17 military service, the issue will be resolved .
Finally, the Pakistan Air Force will also use the data chain technology to achieve communication between different platforms for safety data transmission. In 2009 PAF expect to have Saab 2000 ready and gain the ability to use data links, JF-17 will also possesses advanced electronic warfare system, which is still in shrouds, New aircrafts will also have the missile attack Early Warning System (MAWS) sensors. With the new improvements in electronic warfare capability, PAF bekieves that the JF-17 once put into service will be second only to the F-16C BLOCK 52.
Domestic production JF-17
In 2008, Pakistan is confident of producing annualy 15 aircrafts, and gradually increase to an annual 25 to 30. Pakistan may double the production capacity if PAF wants the replacement of existing inventory on rapid and enhanced time table.
Pakistan is also hoping that 50% of the electronics and fuselage will be locally produced in Pakistan.