Its quite some dense reading, at least the author tries to make some effort on it. Feng pretty much said it all, much of the stuff appears gleamed online, then given analysis and summary. IMO, the first part of the article seems a more interesting before he drifted to the range, radar, avionics and engine issues. Here is a google translation on his comments on the aerodynamics. Its a long analysis though to explain the obvious, the expanded LERX allows the plane to maneuver at higher angles of attack. Also he is correct in the observation that the LERX and the DSI adds to the negative stability of the plane (will make the plane pitch up automatically requiring an FBW needed to keep the nose down in oscillating movement). The LERX will move the center of lift forward, while the weigh reductions in the front as a result of the DSI implementation will move the center of gravity backward. Hence this also improves the plane's maneuverbility.
According to the information obtained by the author, with surfers and explore! 1. 1 configuration. side of Xiaolong 04 and 16 similar to the configuration, Medium used pneumatic normal aspect ratio wing edge of the layout, highlighted the strong performance of low-altitude and high-subsonic mobility. But in the details, the two were different, Xiaolong 04 : First, the edge of the area and more than 01 planes. also much higher than the F-16. Aircraft wings are designed to improve the edge of the lift-to-drag ratio under a certain angle of attack, improving the performance of the aircraft at high angles of attack. But using such a large edge design of the aircraft is not, it is estimated that only a F-18E/F. Trouble from the edge of the 5.2 m 2 to 7 m 2, increased by 34%. It will not only raise the maximum lift coefficient aircraft, taking off and landing capabilities. also greatly enhanced the mobility of the aircraft at high angles of attack. extremely powerful vortex edge of the wing airflow postpone the occurrence and development. F-18E/F excellent performance at high angles of attack apparently inseparable from its side of the wing design. Meanwhile, behind the Xiaolong 04 / end up greatly, bow torque at high angles of attack can provide. Xiaolong 04 while increasing the use of its high angle of attack expected to further enhance mobility! But more important role is that of Xiaolong 04 will be significantly increased while the focus of aerodynamic brought forward. We know that while the focus of the aircraft is located, Lift edge of the vortex caused by the contribution of the wing while washing aerodynamic flow will significantly toward the center. Therefore side of the aircraft configuration is usually static longitudinal instability, active control technology needed to be addressed. For example, the F-16 is a typical "relaxed static stability" with the conventional design : layout, F-16 wings moved forward by 40.6 centimeters, so aerodynamic center forward. M0.9 at its static stability in slightly negative, and 8% at M1.2. Aerodynamic focus toward growing cause of the border, Xiaolong 04 will be the focus might change (after I speculated that it might be a slight shift : DSI weight because the more obvious the former fuselage, Yields rear edge of the electronic module will be partially offset by the increased weight and nose). Aerodynamic focus light Xiaolong 04, the focus changes I guess Xiaolong 04 earlier in the static stability will be further relaxed. And the use of "the entire longitudinal flight control authority fax + 40 degrees more than two simulated redundancy backup" system will be fully satisfy the static stability After the relaxation of control! Xiaolong 04 relaxed static stability will not only further enhance their mobility, More importantly, will be greatly reduced in the span of supersonic trim resistance and help span performance of the supersonic, DSI combination of the weight and the weight of the whole growth pushed down, The greatest number may be more than 04 M M1.6 the biggest increase in the original design! Of course, increasing the edge of the edge of the vortex induced intensity can also lead to larger aircraft pitch moment of non-linear problems, Early mechanical-hydraulic control system's apparent inability to solve, but a good example of Xiaolong 04 flight control solution! 2. Details from the wing of the main wings, Xiaolong 04 and F-16 are different, Xiaolong 04 wing leading-edge sweep angle of 42 °, composite wing bending and torsion, and the latter leading edge sweep angle of 40 °. Aspect ratio of about 3.0, both front and rear wing. F-16 wing no reverse! Contrast can see that Xiaolong 04 of the wing leading edge sweep angle greater aspect ratio smaller than the root shoot, Airfoil closer delta, in a large range of airfoil stall characteristics, and inter-and supersonic flight resistance small! Is likely to be absorbing the essence of the Russian type pneumatic three generations! Even more noteworthy is that Xiaolong 04 in a front flap with the same strain J-10 on the basis of bending and torsion using a composite wing design No composite wing bending and torsion and 16. Why? Design, I believe that this may be related to Xiaolong 04 delta is closer to the airfoil, delta is the biggest drawback of induced resistance, easy airflow vortex formation, loss of front lift. With the front flap and using composite reversed, can improve the overall speed of the largest lift-to-drag ratio. India's LCA has a similar design, I see in inspection data on the Indian side in the LCA had explained his comments : He said the purpose of this design is used to improve the characteristics of wing lift, as he thought the wing dihedral angles of attack. first stall at high angles of attack, time pressure center moves, bow torque produced, and yet Winglet stall. Therefore horizontal control. That the design can be used to enhance the lateral stability of aircraft at high angles of attack. As we all know, single Yields Yields larger aircraft to fly at high angles of attack is the reason, Yields will be shielded fuselage turbulence lose lateral stability, thereby restricting the mobility single Yields aircraft at high angles of attack. If the speculation is true, then the combined side of the design Xiaolong 04 will increase their ability to fly at high angles of attack. able to its excellent maneuverability at high angles of attack! Gen will bring slightly smaller than Winglet flutter, usually cut with a sharp or heavy objects to be resolved Xiaolong Winglet whose every missile in flight test of time with this estimate, and the increase in the electronic module Yields dropped after a sharp cut. While it can be resolved flutter, but feel a bit uncomfortable in the number of visual!
Last edited by crobato; 02-27-2007
