Over the past few years, a lot of information has appeared on Western and Asian military-analytical resources regarding the development and integration of specialized suspended "stealth" containers on tactical fighters of the transitional and 5th generations, designed to accommodate guided missile weapons of the "air-sea / surface" / Radar ", as well as guided air combat missiles of medium and long range. This "stealth" unloading, which has an ultra-low radar signature in hundredths of a square meter, opens up unique tactical and technical advantages for the flight crew, consisting in the possibility of suspension on fighters with 60-70% combat load while maintaining the standard effective scattering surface characteristic of machines, under the wings of which there are only a pair of close air combat missiles with infrared seeker.
As applied to tactical fighters of the “4 ++” generation, these suspended containers with a small radar signature allow approximately 1, 2-1, 3 times to reduce the detection range of enemy sea, land and air-based radar systems. With regard to the 5th generation vehicles, the value of the suspended "stealth unloading" lies in the possibility of delivering a larger quantity of missile weapons to the battlefield without the need to place them on open hardpoints, which all leads to an increase in the RCS of the aircraft, because the internal weapon compartments are not able to accommodate a large number of missile and bomb "equipment". The calculated effective scattering surface of standard 4/5-meter "large-caliber" stealth containers is estimated at about 0.02-0.05 m2, which increases the standard RCS of a tactical stealth fighter of the J-20 type (0.4 m2) by only 4-6% (up to about 0.5 m2), and this is an approximately 15-kilometer increase in the detection range of the enemy radar. If additional weapons were attached to the hardpoints in a standard "open" configuration, they would receive an increase in the detection range of enemy radars of the order of 70-150 km (depending on the RCS of the placed missiles). Which well-known tactical fighters have stealth containers in their armament kits?
The most famous flying prototype of the fighter, equipped with an outboard inconspicuous container, is the latest modification of the Super Hornet - F / A-18E / F "Advanced Super Hornet", flight tests of which began in 2013. In order to increase the range of action, 2 large conformal fuel tanks are installed on the fuselage of the carrier-based fighter. An "Enclosed Weapons Pod" (EWP) stealth weapon container is located on the central ventral pod. The container of this type is equipped with two large doors with a compact hydraulic opening system, behind which is hidden a very impressive arsenal of missile and bomb weapons.
Based on the photographs of the Advanced Super Hornet, as well as technical sketches of the EWP provided by Boeing, one can see that one container holds the following weapon configurations: “4 x AIM-120C-7 / D”, “2 x AIM- 120D and 6 GBU-39 SDB ", or 1 corrected planning bomb BLU-109ER; the JSM (Joint Srike Missile) long-range multipurpose tactical missile, developed jointly by the Norwegian Kongsberg Defense & Aerospace and the American Lockheed Martin, can also be deployed to equip F-35A / B / C fighters. The EWP container makes it possible for the Advanced Super Hornet tactical fighter to keep the EPR at the level of 0.8-1 m2 when properly loaded with modern strike missile and bomb weapons and the AMRAAM family air missile system. It is also known that similar containers are being developed for the Chinese advanced stealth fighters J-20 and J-31, as well as the modernized American F-15SE "Silent Eagle". But with these fighters, the new concept of external placement of weapons is not going to be limited.
As it became known on June 7 from the Japanese publication "The Diplomat" with reference to an anonymous Russian aeronautical specialist, suspended containers with a reduced radar signature are being developed for the domestic promising 5th generation aircraft complex T-50. In particular, it is indicated that it is necessary to place large Onyx missiles (BrahMos in the case of Indian FGFAs) and Kh-35UE Uranus subsonic anti-ship missiles in containers. With the fact that the huge 2.5-speed anti-ship missiles "Yakhont" (PJ-10 "BrahMos") cannot be placed in the internal compartments of the T-50 PAK FA (or FGFA), it is still possible to agree with an unnamed Russian "specialist", but here it is certainly impossible to calmly accept his statement about the impossibility of placing anti-ship Kh-35UE in the internal compartments of the PAK FA.
Armed with a ruler and photographs of the T-50 taken from the lower hemisphere, as well as drawings and sketches from specialized forums, we can conclude that the length of the two central weapon compartments is approximately 4700 mm, the width is about 1200 mm, which is absolutely not enough to accommodate the missiles of the family 3M55 "Onyx" ("Yakhont"), the aircraft version of which has a length of 6100 mm. There is no possibility of placing "Yakhonts" and due to the shallow depth of the weapon compartments, which ranges from 550 to 600 mm. A large depth of these compartments is excluded, since most of the internal space of the gargrot, up to the tail spinner with the antenna post of the rear-view radar with AFAR, is assigned to the main fuel tank of the T-50 fighter, which provides a combat radius of 1000 km at supersonic cruising speed (from 100% fuel), at subsonic speed the range increases to 2150 km without PTB and up to 2700 with PTB. The total mass of the fuel reaches 11100 kg (without PTB). Let's go back to the internal armament bays of the T-50.
Despite the fact that they are not capable of accommodating the Yakhonts purely technically, a completely different situation is developing with the Kh-35UE anti-ship missiles. These missiles have a diameter of 420 mm, a length of about 3850 mm (in aircraft version, without an accelerator); at the same time, with the front and rear empennage folded, the Kh-35UE missile is easily "squeezed" into a spatial rectangular parallelepiped with dimensions of 3.85 x 0.6 x 0.55 m. Therefore, the Kh-35UE can be used from the internal weapon bays of the PAK FA … Nevertheless, there are difficulties with the adaptation of attachment points on the rocket with the UVKU-50L suspension unit. Despite the fact that the latter is almost flush with the upper surface of the weapons compartment, the attachment points of the Kh-35UE are not on the side generatrix of the hull, but on the upper one, which is why the protruding air intake of the rocket is located at the bottom. In other words, we add about 100 mm of the width of the air intake to the diameter of 420 mm, which may well interfere with placement. To avoid such problems, it is quite possible to transfer the attachment points on the Kh-35UE rocket body from the upper surface to the side surface. In this case, the air intake can be deployed on its side, which will save space in the internal weapons compartment.
In addition to the placement of the Kh-35UE (with the above adaptation), the T-50 armament bays can also receive specially "sharpened" for them multipurpose / anti-radar tactical missiles Kh-58USHKE (TP) with a body diameter of 380 mm and a length of 4190 mm, subsonic tactical X- 59MK2 (made in a square case with rounded edges 400 x 400 mm and a length of 4.2 m), as well as ultra-long-range URVV RVV-BD with a diameter of 380 mm and a length of 4060 mm. It seems that this range of weapons is sufficient, especially considering that each compartment can take up to 3 air combat missiles of the RVV-SD type or the RVV-SD missile-direct-flow type "Product 180-PD". Nevertheless, a completely logical question arises: does the T-50 need additional suspended "stealth" weapons containers, placed on the root underwing points of the suspension?
The answer is appropriate: they are needed, but only at the time of performing a narrow range of shock operations. This is justified by the fact that in order to carry out a wide list of tasks in a theater sector saturated with enemy units, a significant amount of missile weapons is needed, which simply will not enter the internal compartments. Moreover, such containers can accept large-size anti-ship missiles such as Yakhont, Kh-74M2, or an aviation version of the Zircon hypersonic anti-ship missile system (if a similar one is still developed).
But we can say with confidence that any suspension systems for the delivery of missile and bomb weapons also have a negative feature, expressed in an increase in aerodynamic drag, which entails an increase in fuel consumption and a noticeable decrease in the combat radius of action. Even worse, massive suspended containers impose serious restrictions on the available overloads when maneuvering the carrier due to the high loads on the structural and power elements of the wing and fuselage, and such a prospect is absolutely useless for a fighter to gain air supremacy. Moreover, the information about the "tricks" observed in the T-50 with a "break" of the glider at low altitudes and speeds of more than 500 - 600 km / h has not been refuted. The "etiology" of these phenomena is unknown, but heavy containers are clearly not needed for our PAK FA, especially if an F-22A equipped with AIM-120D missiles is in the air from the enemy's side. Their installation is advisable only on the vehicles of the squadron that will be sent exclusively on a strike mission, while other units or squadrons of T-50 / Su-35S will be engaged in gaining air superiority and intercepting enemy air attack weapons.
If we try to look at the concept of using T-50 weapons in a slightly different plane, then a much more expedient solution would be far from using suspended "stealth unloading", but the development of modern compact air attack weapons capable of accommodating 4, 6 or more units even in one of the two internal weapons bays, leaving the second for medium and long-range air combat missiles, especially since the volume of the T-50's bays is much larger than that of the F-22A Raptor or F-35A Lightning-II. For your information, neither Lockheed Martin specialists nor engineers at the US Air Force Research Laboratory are absolutely not eager to "hang" their Raptors and Penguins with heavy, inconspicuous suspended weapons containers. Instead, all the emphasis is on equipping vehicles with ultra-small gliding "narrow" bombs such as GBU-39 / B (SDB I) and GBU-53 / B (SDB II), which the F-22A can hold in the amount of 12 units. in the main ventral weapon compartments.
Also, for the main internal fuselage compartments of the Raptor, the configuration "8xSDB I / II and 2xAIM-120D" is provided, thanks to which the pilot has the ability to carry out a full-fledged strike operation against several enemy ground targets at once, plus he can conduct a short long-range air battle with two enemy fighters. As for our T-50 PAK FA, which has a clear advantage over the F-22A and F-35A in the form of larger compartments, here, due to the banal lack of development of small-sized high-precision weapons, can fit either 4 (in case of successful adaptation UVKU-50L), or only 2 long-range tactical missiles Kh-59MK2. For a promising 5th generation aviation complex, this situation is clearly not the norm, because even in tiny Israel, the Rafael company has developed a compact planning UAB Spice-250 with an 80-kilogram warhead and a combined control system for inertial and satellite modules, and also optoelectronic homing head. The circular probable deviation of this UAB does not exceed 3 m, and the operating range reaches 100 km when dropped from high altitudes. The bomb was developed taking into account the requirements of Hel Haavir, and has a very small radar signature (EPR about 0.02 m2), which significantly reduces the detection range of any modern air defense system. It can only be intercepted by such air defense systems as S-300PM1, S-400, Buk-M3, Pantsir-S1 and Tor-M2E in the range of ranges from 5 to 25.
The "Spice-250" bomb is so compact that the Israeli Air Force F-16I "Sufa" tactical fighters can receive 16 units each on external hardpoints. of the given WTO. F-15I "Ra`am" can carry 28 bombs of this type, and therefore medium-range air defense systems have big problems. A much more visible threat will begin to come from the ultra-small Spice in the coming years, when Hel Haavir, with the support of Rafael, will begin integrating these guided gliding bombs into the armament kit of the F-35I Adir stealth fighters.
In view of the above circumstances, it can be concluded that even before the VKS fighters of the 5th generation T-50 PAK FA are adopted by the Aerospace Forces, it will be necessary to develop promising planning air attack weapons with a hull diameter of less than 200 mm and a length of up to 2.3 m, which should maximally effectively use the space of the inner-fuselage weapon compartments. As you know, our specialists have vast experience in the design of small-sized elements of high-precision weapons. Take, for example, the S-5/8 / 13Kor family of guided missiles, designed on the basis of the 57- / 80- / 122-mm aircraft unguided rockets S-5, S-8 and S-13. The effective scattering surface of these "smart" missiles is from 0.05 to 0.15 m2, which is comparable or even less than that of the Rafael gliding UAB "Spice-250". Back in the late 90s. AMETECH was able to successfully convert these NURS into two-stage high-precision missiles, the combat stages of which are equipped with impulse gas-dynamic engines of transverse control, as well as semi-active laser seeker. Interception of such WTO elements, due to low RCS and speed, is an extremely difficult task even for the most modern air defense systems, and the only exception can be active protection complexes.
Nevertheless, these missiles can be considered only as "long-range" concepts for the development of even more promising compact air attack weapons for the T-50 fighter, since their range does not exceed 9-10 km, and the launch can be carried out exclusively from open UB blocks -32M, B-8M or B-13L. To use the PAK FA from the internal armament compartments, and even at a distance of tens of kilometers, it would be necessary to equip these shells with a modular set of folding wings and a digital device for delaying the launch of solid propellant rocket motors of the upper stage at the moment of exiting the armament compartment; and the aforementioned high-precision shells of the "Threat" complex, unfortunately, turned out to be absolutely unclaimed in the family of the Aerospace Forces! What can we say about their transformation into dive air attack weapons or other advanced "buns" of network-centric warfare. Consequently, the main goal should be to design a fundamentally new small-sized high-precision weapons, but not to focus on bulky "stealth" containers, which negatively affect the maneuverability and range of the T-50 PAK FA.
