Modern combat aviation goes back to a common ancestor - A-5 "Vigilent", in the design of which such elements as were for the first time combined: "high-wing" scheme; fly-by-wire control system (ESDU); trapezoidal wing of medium aspect ratio and sweep;
- fuselage rectangular in cross-section; all-moving horizontal tail; a curious find of North American engineers - bucket-shaped air intakes with a deflecting wedge.
Strictly speaking, this is not even "Vigilent", but an even earlier project of 1955, which remained on paper (North American WS-300A). The main difference from the A-5 was the two-finned tail assembly. The legs of all modern fighters grow from it.
The two-flight reconnaissance bomber A-5 Vigilante ("self-proclaimed sheriff", "avenger") was created to deliver nuclear strikes from the decks of aircraft carriers. In December 1960, Vigilent set an absolute world record, climbing to a height of 27 kilometers with a load of 1000 kg of bombs. Despite its large size and take-off weight of 28 tons (for comparison: MiG-21 - 13 tons, Phantom - 20), it was distinguished by its amazing maneuverability and, being lightly equipped, could conduct air battles on an equal footing with fighters. It accelerated to the speed of sound without switching on the afterburner. While behind the canopy was a tiny porthole - the cockpit of the bombardier navigator. With all the outrageous performance characteristics, the "Avenger" remained a two-seater bomb carrier! But the most amusing feature of the Vigilent was the weapons bay, made in the form of a pipe, locked with a knockout plug.
A hurricane awl with a "nuclear filling" could well pretend to be a fifth generation fighter. Joke? Perhaps.
The superbomber failed to drop a single bomb, but Vigilent managed to see the hot sky of Vietnam in the role of a long-range reconnaissance RA-5C. Aircraft of this type recorded the results of the bombing, appeared over the targets after the strike groups had worked on it, and the awakened Vietnamese air defense was put on full alert. Despite the exceptionally high flight characteristics, 18 "Avengers" crashed into the jungle.
While the A-5 was setting records, photographs of the Vigilent from Western aviation magazines (and probably something else from the almighty KGB) were placed on the table of the chief designer of the Mikoyan Design Bureau. A promising scheme was the basis for the E-155 project, the future MiG-25 fighter-interceptor (development began in 1961).
Domestic engineers have brought the scheme to perfection. The main external difference between the MiG and the Vigilent was the two-finned plumage. The American car suffered from poor directional stability - powerful vortices, breaking off the edges of the air intakes, rocked the plane, despite the presence of a huge stabilizer. The Mikoyanites applied a beautiful solution, letting the vortices pass between the keels. To be fair, the Yankees weren't dumb either. But their car was intended to be based on aircraft carriers: the single keel of the Vigilent folded to one side.
Freed from ship restrictions and lost all problems at once, the Soviet MiG soared 37 kilometers with a candle. Which unequivocally hints at the fantastic energy of the car. All-steel construction, equipped with two roaring R15BD-300 with a total thrust at the afterburner of 22 tons. The maximum take-off weight of the MiG-25 reached 40 tons, of which 17 tons were kerosene.
The sparkling MiG star could not remain unnoticed (and even more so unheard) by our potential friends. Contrary to rumors about the dire consequences of the hijacking of the MiG-25 to Japan, the American military attaches had a chance to get acquainted with the three-plane interceptor 9 years earlier, during the air parade at Domodedovo in 1967. However, the CIA probably found out about the E-155 project, as soon as the center lines of the future aircraft lay on the drawing boards.
The right to answer is for McDonnell-Douglas. In the summer of 1972, the Yankees raised a prototype of the F-15 fighter into the air (the start of work on the FX program was 1969). In the dark with closed eyes "Eagle" can be quite mistaken for the MiG-25: a similar combination of a trapezoidal wing with a two-keel fuselage and side bucket air intakes. But what is it? The fuselage of the F-15 seems to be a little "flattened". At external examination it is impossible to determine the place of its articulation with the wing.
This was the main secret of "Eagle". The Yankees came up with an integral layout. At first, acting timidly and carefully, they took a step to ensure that some of the lift is generated by the fuselage itself.
In parallel with the F-15 project, the F-16 project is born. A side branch in the evolution of fighters. Another 30 years will pass, and the Falcon will once again merge with the common tree of fighter aircraft, adding a portion of unique technical solutions to its genotype. However, this is still far away … Outside the window, 1974. The Yankees are working on a light, highly maneuverable aircraft. Little "Falcon" does not look like its peers at all (maybe except for general proportions and a wing of moderate aspect ratio and sweep). Just one engine. One keel. And, of course, the main falcon's secret is the developed nodules in the wing root (“vortex generators”). With their help, the Yankees are trying to maintain control at critical angles of attack, allowing the miniature F-16 to fight on an equal footing with any fighter. This is also facilitated by the integral layout and the prohibitive thrust-to-weight ratio of the "kid".
The distribution has passed. A tough combination on the table. The stakes are high. There are billions of currency units in the bank.
The players remaining at the table show their cards. A trump card is hidden in the sleeve of the MiG - the light front-line fighter MiG-29 (first flight in 1977). The integrated aerodynamic scheme, brought to perfection, coupled with a developed inflow-vortex generator and perfect wing mechanization (slotted flaps, ailerons, deflected toes). The Mikoyan Design Bureau employees are the first in the world to break into super-maneuverability!
KB Sukhoi discards cards. Fold. Their prototype of the fourth generation fighter (T-10) does not confirm the declared flight characteristics. Too sharp sag edges, curved leading edge of the wing without the possibility of using automatic socks and keels too close. Stability and controllability at supercritical angles of attack are not provided …
Failure is not a cause for despair. In record time, a new prototype of the T-10S is being prepared (first flight - 1981), which later became the legendary Su-27.
New deal of cards. Sukhoi has a unique combination in his hands. Domestic know-how is added to all of the listed findings of engineers on both sides of the ocean (two-keel tail assembly / vortex generators / integral layout / wing mechanization). Static instability in the longitudinal channel. We translate into Russian: for various combinations of Mach numbers and angles of attack, the point of application of aerodynamic forces constantly moves back and forth relative to the aircraft's center of gravity. As a result, the Su-27 is relentlessly trying to "rears up", making somersaults over the tail without any participation of the pilot.
To control the Su-27, a computer is required with an algorithm in its memory of which speed parameters and angles of attack correspond to the required position of the control surfaces. Controlling such a machine without the aid of an EDSU is excluded. At least, no one seriously tried it - without complex calculations, it is clear that the Su-27 without an ESDU responds inadequately to the movement of the RSS. This aircraft is not designed to fly in a straight line. The element of "Drying" is aerobatics!
Noon, XXI century. Next hand. American "Lockheed Martin" recklessly calls all the bets: a new class of military aircraft has been created overseas, successfully combining aerodynamics and stealth technology. In the silhouettes of the F-22 and F-35, it is difficult to discern the features of aircraft of bygone eras, but the essence remains the same: the high-wing layout, a two-fin tail unit, a trapezoidal wing, similar vortex aerodynamics and "buckets" of the side air intakes of the engines. Greetings from Vigilent and the WS-300A from the fifties!
In the designs of fifth generation fighters, there are no developed influxes, PGO and other classical solutions. Instead of all this - a lateral line-vortex generator in the nose of the fighter with an even greater degree of integration of the wing and fuselage. In addition, there is a high thrust-to-weight ratio and “pure” aerodynamics (this implies the rejection of external pylons and suspensions in the BVB.) Optionally, a controlled thrust vector of the engines.
The answer lies with Russian designers. The multipurpose PAK FA adheres to a similar concept, using the impressive aerodynamic groundwork obtained in the creation of fourth generation fighters. The main difference from the "Raptors" is a purely domestic engine circuit with OBT. Domestic and foreign designers have different ideas about the role and design of this unit.
The flat nozzles of the American F-22 remain wedged in their normal position at angles of attack less than 20 degrees. and deviate synchronously, in the same direction. OVT is used only for pitch and roll control to enhance the action of the horizontal tail at low speeds and critical angles of attack (close air combat).
In contrast to the American scheme, domestic experiments with OVT demonstrate the opposite picture: nozzles with OVT deviate differentially, in different directions (so far pseudo-sequence is deviation only along the diagonal). Moreover, the engines themselves are located at a sufficient distance from the CG of the aircraft.
As a result, the advanced Su-35S, which is, if not an analogue, then very close in aerodynamic design to the PAK FA, demonstrates impossible aerobatics.
Su-35S abolished the very term "turning radius".
Tang Yanshi, Ch. engineer of the Chinese aircraft corporation AVIC.
Another deal of cards! We have not the weakest combination on our hands. And a good position - our word will be final. We see the actions of other players and are able to analyze their mistakes. Will we be able to take full advantage of our position or will we yield to equally strong opponents in the fight?
The 100-year history of Russian aviation testifies to the success. We will cope and win!
Epilogue. Terrible prophecy
Borrowing aerodynamic designs is not a big secret. All planes speak the same language, the language of aerodynamics (gas dynamics). And if a separate team of researchers achieved noticeable success, its achievements, as the most promising, were immediately copied by the rest.
Vigilent - MiG-25 - F-15 / F-16 - MiG-29 - Su-27 - Raptor - PAK FA.
Tracking the chronology of the creation of each fighter, you can personally see what new elements and in what order were introduced into the design of each new generation. Of course, we are not talking about blind copying. Nevertheless, all of these aircraft are united by a number of clearly visible solutions, the progenitor of which was the WS-300A project.
The now forgotten team of brilliant researchers, which predetermined the appearance of fighter aircraft for a century ahead.
The world is not devoid of variety. In addition to the Russian-American school, there is another distinctive school of aircraft construction. The French, Swedes and other "Eurofighters" adhere to their own view of combat aircraft, traditionally creating tailless fighters. However, this is a completely different story …
