Manticore
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Combat Aircraft Projects & Designs - Index in 2nd post
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Manticore
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Manticore
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Two very different area wings can provide the same lift by flying at different angles of attack (and hence different lift coefficients). This is a big reason why aerodynamicists tend to work in coefficients rather than absolute forces.
Since weight is usually an input, the lift is constant. So more area means less lift coefficient (same lift), and lower drag.
Sweep, span, and area are all totally independent.
Wingspan
Wing loading
In aerodynamics, wing loading is the loaded weight of the aircraft divided by the area of the wing.[1] The faster an aircraft flies, the more lift is produced by each unit area of wing, so a smaller wing can carry the same weight in level flight, operating at a higher wing loading. Correspondingly, the landing and take-off speeds will be higher. The high wing loading also decreases maneuverability. The same constraints apply to birds and bats.
Wing loading is a useful measure of the general maneuvering performance of an aircraft. Wings generate lift owing to the motion of air over the wing surface. Larger wings move more air, so an aircraft with a large wing area relative to its mass (i.e., low wing loading) will have more lift at any given speed. Therefore, an aircraft with lower wing loading will be able to take-off and land at a lower speed (or be able to take off with a greater load). It will also be able to turn faster.
Fuselage lift
The F-15E Strike Eagle has a large relatively lightly loaded wing
A blended wing-fuselage design such as that found on the F-16 Fighting Falcon or MiG-29 Fulcrum helps to reduce wing loading; in such a design the fuselage generates aerodynamic lift, thus improving wing loading while maintaining high performance.
[edit] Variable-sweep wing
Aircraft like the F-14 Tomcat and the Panavia Tornado employ variable-sweep wings. As their wing area varies in flight so does the wing loading (although this is not the only benefit). In the forward position takeoff and landing performance is greatly improved.[11]
[edit] Fowler flaps
The use of Fowler flaps increases the wing area, decreasing the wing loading which allows slower landing approach speeds.
Since weight is usually an input, the lift is constant. So more area means less lift coefficient (same lift), and lower drag.
Sweep, span, and area are all totally independent.
Wingspan
Wing loading
In aerodynamics, wing loading is the loaded weight of the aircraft divided by the area of the wing.[1] The faster an aircraft flies, the more lift is produced by each unit area of wing, so a smaller wing can carry the same weight in level flight, operating at a higher wing loading. Correspondingly, the landing and take-off speeds will be higher. The high wing loading also decreases maneuverability. The same constraints apply to birds and bats.
Wing loading is a useful measure of the general maneuvering performance of an aircraft. Wings generate lift owing to the motion of air over the wing surface. Larger wings move more air, so an aircraft with a large wing area relative to its mass (i.e., low wing loading) will have more lift at any given speed. Therefore, an aircraft with lower wing loading will be able to take-off and land at a lower speed (or be able to take off with a greater load). It will also be able to turn faster.
Fuselage lift
The F-15E Strike Eagle has a large relatively lightly loaded wing
A blended wing-fuselage design such as that found on the F-16 Fighting Falcon or MiG-29 Fulcrum helps to reduce wing loading; in such a design the fuselage generates aerodynamic lift, thus improving wing loading while maintaining high performance.
[edit] Variable-sweep wing
Aircraft like the F-14 Tomcat and the Panavia Tornado employ variable-sweep wings. As their wing area varies in flight so does the wing loading (although this is not the only benefit). In the forward position takeoff and landing performance is greatly improved.[11]
[edit] Fowler flaps
The use of Fowler flaps increases the wing area, decreasing the wing loading which allows slower landing approach speeds.
Manticore
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CANARDS
Modern high-speed aircraft, especially military, are very often equipped with single or compound delta wings. When such aircraft operate at high angles-of-attack, the major portion of the lift is sustained by streamwise vortices generated at the leading edges of the wing. This vortex-dominated flow field can breakdown, leading not only to loss of lift but also to adverse interactions with other airframe components such as the fin or horizontal tail
The performance of a canard design depends strongly on the amount of lift that the canard must carry. This is set by stability and trim requirements.
An analysis of the effects of canard shape, position, and deflection on the aerodynamic characteristics of two general research models having leading edge sweep angles of 25 and 50 degrees is presented. The analysis summarizes findings of three experimental transonic wind-tunnel programs and one supersonic wind-tunnel program conducted at this Center between 1970 and 1974. The analysis is based on four canard geometries varying in planform from a 60-degree delta to a 25-degree swept wing, high aspect ratio canard. The canards were tested at several positions and deflected from -10 to +10 degrees. In addition, configurations consisting of a horizontal tail and a canard with horizontal tails are analyzed. Results of the analysis indicate that the canard is effective in increasing lift and decreasing drag at Mach numbers from subsonic to high transonic speeds by delaying wing separation. The effectiveness of the canard is, however, decreased with increasing Mach number. At supersonic speeds the canard has little or no favorable effects on lift or drag. It is further shown that the horizontal tail is a superior trimming device than the close- coupled canard at low-to-moderate angles of attack and that a configuration consisting of canard, wing, and horizontal tail is superior in performance, to either canard or horizontal tail at high angles of attack.
The Canards in the Lavi have also dihedral but also they are far too close to the wings in fact over them-- The Eurofighter`s are not as close to the wings as those on the Lavi, the position has to do with drag/lift ratio, the best combination is high aspect canards low aspect wings check the Eurofighter has also strakes -- chinese J-10 also the canards are not too far from the wing, however are not so close as those in the Lavi and Rafale, both the Eurofighter and J-10 have the least drag canard delta wing configuration specially good for a fast aircraft -- the Viggen has low aspect wings and canards, these low aspect canards and wing are best configured for high lift
long-coupled canard and close-coupled canards= The two approaches to canard fighter design are more different than the names imply.
In a close-coupled design, the developers were trying to optimize the aerodynamic interaction between the wing and canard, with the objective of improving aircraft lift-to-drag and high angle-of-attack performance. For the Lavi , this means that these airplanes can fly further on less fuel than their conventional counterparts.
In a long-coupled design like the Eurofighter Typhoon or X-31, the developers were trying to minimize the canard-wing interactions, and simplify their aerodynamic design process. They still gain the benefits of improved aerodynamic control at high angles of attack, but they do not see an appreciable improvement in the airplane's lift to drag ratio.
You can tell the difference between the two approaches to canard fighter design, based on how close the canard is positioned to the airplane's wing (measured in mean chord lengths), and also by whether the canard is positioned above or below the wing. On the Lavi, J-10, Kfir, Gripen and Rafale, the canard is positioned just ahead of, and above the wing, to maximize the aerodynamic interaction between the two. On the Typhoon and X-31, the tips of the canard are canted downwards, to ensure that the canard tip vortices are swept below the wing.
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J-11D/E (= Stealth J11 Upgrade)
China's new "JH7B stealth fighter" test flight successful
admin on July 29, 2008 in Military World
According to reliable sources XAC: New Stealth Flying Leopard JH-7B has been successfully flight. New J H-7B is a twin-seat, twin tail layout of stealth, all-weather fighter-bomber. Although the original Flying Leopard "body bone" bottom, but the big thrust to meet the new engine, new Flying Leopard had to be appropriately enlarged body size adjustment. As the new engine's inlet air quantity and unit of engine thrust than the original increase of nearly 50%, plus the stealth shape design needs, the new Flying Leopard can not simply follow and enlarge the body of the original Flying Leopard. New "Spey" engine than the "turbofan WS-9" and "Laosilaisi"
Diameter larger engine, but also short. Therefore, the researchers on the original machine's aerodynamic body shape and internal structure of a drastic improvement! Its great complexity of the workload, no less from the new design of a new aircraft. Because the body is increased so that the machine oil reserves increased significantly, so the J H-7B of the combat radius of several new active duty in the military combat aircraft has a combat radius of leading.
From the outline view; China's "J H-7B" In order to improve performance and strengthen the aerodynamic shape stealth, "JH-7B" uses the world's most popular "S"-shaped inlet, and a new nano-spray suction inlet wave coating to reduce the aircraft radar cross section and positive infrared signal characteristics, and to BWB technology integration, the whole machine the new composite application area increased significantly.
"J H-7B" The way has been improved fuel refueling equipment for the interior in order to further enhance the machine's stealth. Therefore, the "J H-7B" is the first kind of use of computer-aided design modified form of the stealth fighter-bombers.
As the "J H-7B" stealth using a newly developed radar absorbing paint, making the probability of machine to detect much lower. Canopy edge, weapons and weapons-bay doors built with jagged edges, etc. The combination of lines, can effectively reduce radar reflection. Airborne Weapon type used and the plug-in containing a balanced approach, in order to further reduce the infrared signature. J H-7B extensive use of effective stealth measures, its radar cross section (RCS) will be not more than XXX square meters.
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1): J-11: Chinese copy of SU-27 (Shenyang)
2): J-12: Super light single-engine interceptor project in 1960s-70s (Cancelled)(Nanchang)
3): J-13: Medium weight, conventional layout single-engine interceptor project in 1970s-80s(Cancelled)(Shenyang)
4): J-14: Project initiated at the beginning of 21st Century, heavy-weight twin-engine stealth fighter developed from the basis of J-10, aka "Big 10", later cancelled due to 4th-gen fighter R&D proceeding on schedule, experience garnered are to be used on future projects.(Chengdu).
5): J-15: Chinese version of SU-33 with avionics upgrades, carrier-borne version of J-11B, 1st generation of Chinese carrier-borne fighter. (Shenyang).
6): J-16: Chinese version of SU-30MKK with avionics upgrades, variant developed from J-11BS, this is to be a long-ranged fighter-bomber with similar technological level as to F-15K/SG. (Shenyang).
7): J-17: new generation of long-ranged fighter-bomber based on J-11B, to something like the SU-34 but integrated with certain stealth technology. (Shenyang)
8): J-18: new generation of carrier-borne fighter with stealth characteristics, develop from the basis of J-15基础上, integrated with many of the 4th-gen technology. This proposal, along with that of J-19, have received the go-ahead in 2009. (Shenyang)
9): J-19: high-end, major modification to J-11B design to 4th-gen stealth standard, this is designed as a 4th-gen heavy-weight multi-role fighter to serve alongside the J-20.(Shenyang)
Tunna 
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