Individual weapon systems rarely, if ever, are so good that they can be viewed separately from the entire complex of weapons that work as a well-oiled fighting machine. Most of the time, various seemingly unrelated assets support each other to maximize the efficiency of the whole system. However, there are some exceptions to this. On this occasion, the topic is precisely about one such system, specifically the now legendary Su-35S, the long-range sniper of the Russian Aerospace Forces (VKS), as well as its most widely used top-of-the-line fighter jet. To better understand how much of an impact this fantastic flying machine has had on the battlefield, as well as its strategic impact in various parts of the world, we have once again decided to interview an expert with the KRN.
For our new readers, we want to point out that KRN is a Belgrade-based military-focused think tank that includes pundits from various fields, including missile technologies, military aviation, naval and land warfare, etc. One of their most prominent members, going under the name Major Irbis, is an expert in all of the aforementioned fields of military science, but is particularly focused on military aviation. Just like his esteemed colleague Captain Liner did the last time in an interview about the then-upcoming Kiev regime counteroffensive, where he correctly anticipated and predicted its course with shocking precision, Major Irbis also graciously took the offer to give us the KRN’s take on the Su-35S. Without further ado, let’s dive right into the interview with our esteemed guest.
– First of all, thank You for accepting our invitation for the interview. We highly appreciate Your informed opinion on this topic and can’t wait to hear what You have in store for us.
It’s truly an honor and thank You very much for the invitation. Firstly, it would be good to reiterate what my esteemed colleague Captain Liner already said about KRN and why we have been refusing to conduct interviews with most news outlets. Simply put, we engage in professional reporting and research on military topics in a way that is the complete opposite in comparison to all the melodrama of the mainstream media. This is particularly true when it comes to systems such as the Su-35S. As you stated, it is a truly state-of-the-art machine that has been brought to near perfection when it comes to its operational capabilities.
– We’ll get to that very shortly. But before we do, could You briefly explain what made the Su-35S a hotly debated topic once again recently?
We might have to go back to the second half of April this year to explain that. Namely, at the time, American forces occupying parts of Syria complained that heavily armed Russian Su-35S fighter jets stationed in Syria have flown over their bases in that country. Immediately after that, the AFCENT [United States Air Forces Central] requested the deployment of USAF F-22A “Raptor” fighter jets to counter the Su-35S “Flanker-E”. As you already know, these two jets officially don’t belong to the same generation, as the “Raptor” is a fifth-generation aircraft. However, this hardly changes the calculus for the “Flanker-E”, as it possesses systems and technologies that largely transcend a previously clear delineation of what generations are.
– Also, this wouldn’t be the first time that Su-35S and F-22A will get pitted against each other.
Exactly. It already happened multiple times, including in September 2018. But, on December 13, 2017, in airspace over eastern Syria, VKS Su-35S met the USAF F-22A “Raptor” for the very first time. That day two Russian Su-25SM CAS [close air support] aircraft performed a combat mission. Two “Raptors” tailed them and took provocative actions by dispensing flares. Russian A-50U AEW&C [airborne early warning and control] had been able to track “Raptors” from over 300 km away, even before they took action against Su-25SMs. The A-50U then vectored in two Su-35S jets that soon split. One was flying in a head-on aspect and the other in radio-silence mode to tail the F-22A. That was the first opportunity for the Su-35S to turn on its N035 “Irbis” radar. After setting it to illumination mode, the detection range in angle aspect 0/1-1/4 was 180 km.
– But how is that even possible? Isn’t the “Raptor” a stealth aircraft designed to avoid detection even from much shorter distances?
The reason for that is very simple. The maximum pulse power of the N035 “Irbis” in high PRF [pulse repetition frequency] mode is 20 kW and the F-22A’s frontal RCS [radar cross section] in centimetric X band is about 0.3 m², not the ridiculous 0.0001 m² given by Lockheed Martin back in 2009. Simply put, such RCS is completely impossible to achieve. A fifth-generation fighter like the F-22A is LO [low-observable], but not VLO [very low-observable]. How do we know this? Well, the 1980’s ATF [Advanced Tactical Fighter] program [that the F-22A stems from] had one particular requirement – to reduce the new fighter’s RCS by 100 times in comparison with the fourth-generation F-15 that had a frontal RCS of about 10 m². So, 10 m² : 100 is 0.1 m², not 0.0001. You can reduce the RCS by 10 or 100 times, but you cannot do that by 1000, 10.000, 100.000, a million or a billion times. Laws of physics are the same everywhere in the world.
– Now that You’ve mentioned the RCS and radars, we often hear that the Su-35S is supposedly inferior to Western and other fighter jets because its radar is allegedly only PESA (passive electronically scanned array) rather than AESA (active electronically scanned array). Is this really true and what is Your opinion about that?
Many people seem to be obsessed with AESA. Firstly, it’s not exactly an earth-shattering technology. And secondly, N035 “Irbis” is in fact a hybrid ESA with many abilities of an AESA. N035’s FoV [field of view] is 240° versus 120° in all Western AESA radars. How many Western fighter jets can fly in the upper stratosphere and detect/track low-flying cruise missiles or fly very low and detect/track something that flies at a high altitude? None. How many Western fighters can turn 90° ahead of their target after launching an air-to-air missile in BVR [beyond visual range] combat? Again, none.
– Many Western analysts insist that the Su-35S is no match for the F-22A simply because the former is based on the Su-27. Do You think that’s actually the case?
First of all, everyone should understand that the Su-35S is essentially a new design packed into a Su-27 airframe and its specific role was to fight stealth aircraft such as the F-22A. It’s equipped with sensors and weapons specifically designed to detect/track and engage LO aircraft. Now, I want to point out that the “Raptor” is a very capable aircraft. It has excellent avionics and it’s definitely a challenge for the VKS, which is precisely why they developed the Su-35S. F-22A’s AN/APG-77(V)1 radar can operate in different modes simultaneously, including in air-to-air and air-to-ground, providing excellent situational awareness to the pilot. It can detect aircraft with RCS of 1 m² from a distance of 250 km. However, it’s important to note that the F-22A cannot engage air targets in radio-silence mode because its AN/APG-77 will illuminate radar signals that will be detected by the Su-35S’s SPO-32 “Pastel” ESM/RWR [Electronic Support Measures/Radar Warning Receiver] system.
Also, as I’ve already mentioned, the Su-35S has an X band monopulse N035 “Irbis” hybrid ESA radar with abilities of both PESA and AESA. PESA with two very powerful TWTs [traveling-wave tubes] and AESA with about 1800 TRE [Transmit-Receive Elements or Phase Shifters] inside a hybrid-heterodyne waveguide system integrated into а reflector of a slotted-design antenna. This allows the sending of multiple beams in different waveforms and with different working frequencies within the wideband frequency spectrum and with big frequency agility just like AESA. It can work in different combat modes (air-to-air/air-to-ground) simultaneously and has a radar envelope of 240°, which is double that of the F-22A’s radar. The reflector is movable and has a gyro-stabilized two-step electro-hydraulic gimbal. The maximum instrumented search range in high PRF mode is 400-450 km. N035 “Irbis” has several BVR and WVR [within visual range] combat modes and can automatically track 30 aircraft flying at up to 6000 km/h and engage eight of them.
When comparing the two radars, we can conclude that “Irbis” has a superior FoV, better duty cycle than any AESA (due to its TWTs) and also better sidelobes performance. With it, the Su-35S can engage targets in BVR combat, then turn 90° ahead of its target to reduce the encounter speed and prevent counterattack. Apart from the radar, the Su-35S possesses the OLS-35 IRST [infrared search and track] sensor with an LD [laser designator] and LLLTV [low light level television], something the F-22A lacks entirely. The OLS-35 has a 180° azimuthal FoV and detects incoming fighters flying subsonically (no afterburner) at a distance of about 80 km. The real combat advantage of OLS-35 is that it can be used in complete radio-silence, meaning that the enemy aircraft isn’t even aware that it’s being tracked/targeted.
The Su-35S also has the L175M10-35S “Khibiny-M” jamming/ECM [electronic countermeasures] system with two cylindrical wingtips L265M10-01 stations. Within them are the “Proran” EW [electronic warfare] and “Regata” ECM/jamming stations. Waveguide units in the front and rear of wingtips stations use AESA technology with a wideband spectrum and they are very agile in terms of frequency. The Su-35S’s S-107-1 communications complex with a digital data-link channel can network a total of 16 fighters in one joint patrolling group consisting of 4 basic groups. One four-aircraft group can cover almost 3000 km of airspace with 800 km of distance between two fighters and 400 km in front of them.
For ID/IFF [identification, friend or foe], the Su-35S has the 4283MP multifunctional digital interrogator with decimetric L band AESA with a range of 400 km positioned in its wingslats. There’s also the KOEP-35 navigation-targeting pod (equivalent to LANTIRN [Low Altitude Navigation and Targeting Infrared for Night] used by USAF) with IR, LLLTV and laser channels. Sensor fusion gives the ability to integrate N035, L175M10-35S “Khibiny-M”, SPO-32 “Pastel”, IFF L band AESA that work in radar bands together with OLS-35, I-222 all-aspect EW system and KOEP-35 that work in optical bands.
Another truly unique, but also most secretive system used by the Su-35S is the BOSES-TU “Duel” [БОСЕС-ТУ, stands for Бортовая оперативно советующая экспертная система тактического уровня “Дуэль”] and could roughly be translated as Aircraft Operational Recommendation Expertise System of Tactical Level. BOSES-TU enables the aircraft to be programmed with the capabilities of its adversary in mind, allowing it to track the opponent and recommend optimized decisions to the pilot, creating a fine man-machine balance. And this is only the tip of the iceberg of what it can do and is effectively the first time an advanced AI [artificial intelligence] has been integrated into a combat platform. Apart from the Su-35S, only the new Su-57 has this combat system, with no equivalents anywhere in the world.
– Truly fascinating, but what about the weapons?
The Su-35S has many air-to-air missiles at its disposal. For very long-range engagements there’s the new hypersonic R-37M, while for long-range BVR there is the radar and IR-guided R-27ER/ET and the new R-77-1. For medium-range BVR there’s the older radar and IR-guided R-27R/T and for WVR combat it has the new R-74/M (L and ML). The medium/long range R-27R/ER has the INS [inertial navigation system] + SARH [semi-active radar homing] guidance with the maximum authorized launch distance against large incoming targets being 90-150 km (supersonic launch mode in the stratosphere). The R-77-1 is a modernized version of the Soviet-era R-77 which was the world’s first supermaneuverable BVR missile. The old R-77 was developed to achieve a PH [probability of hit] of 80%.
Both R-37M and R-77-1 have INS+ARH [active radar homing] or SARH (in Q band and X band, respectively) mode in the terminal phase. Both modes can be used simultaneously or separately, depending on the combat situation. It is very difficult, if not impossible, to jam both modes at the same time. Both missiles also have two-way data-link channels. To evade the R-77-1, the enemy fighter jet must turn with a 12G load, which is impossible to achieve for either the aircraft or the pilot. The R-74 (L/ML, L for laser proximity fuse, M for modernized) is an updated version of the Soviet-era R-73/M (L/ML). It’s extremely agile and maneuverable due to its TVC [thrust vectoring controls], the first in the world on an air-to-air missile.
– We often hear that the Su-35S has inferior engines that don’t allow supercruise (flying supersonic without afterburner). Is this true?
The Su-35S has two very powerful AL-41F1S engines with a maximum static thrust of 14500 kgf [kilogram-force] on full afterburner and 9000 kgf of dry thrust. And it’s not true that it can’t supercruise. In fact, its supercruise speed is Mach 1.3, although its flight time in this mode is somewhat limited. However, in order to achieve a much longer supercruise, all it needs to do is reduce speed to Mach 1.1. Also, the engine nozzles can move in a horizontal plane on the upper outer side or bottom inner side. This technical solution gives phenomenal supermaneuverability in post-stall maneuvering mode.
Another technical solution that was applied is its very innovative plasma ignition system in the main and afterburner combustion chambers. The engines, combined with the aerodynamic layout, provide the Su-35S with extreme maneuverability, as well as controllability at supercritical AoA [angles of attack]. The jet simply has no restrictions on the AoA. For the full implementation of all super-maneuverable properties, a special MTC [maneuver-trajectory control] mode has been introduced into the jet’s control system. The MTC switch on the pilot’s stick puts the aircraft into super-maneuverability mode.
– How do you think the Su-35 can change the balance of power in regions where it’s deployed, such as Asia-Pacific (deployed by China) or the Middle East (now deployed by Iran)?
To answer that question, I’d like to quote Lieutenant Colonel David Berke, a US pilot who flew both the F-22 and the F-35. He told the Business Insider that when flying the F-22, his aim wouldn’t be to get in a turning fight with an opponent. Instead, he said he’d use “the F-22’s biggest advantage of stealth” and avoid a WVR aerial duel. However, as I already stated, this “stealth thing” is very questionable when it comes to the raw power of the mighty 20-kW “Irbis”. Reports from official US sources such as the Center for Strategic and Budgetary Analysis indicate that the Russian Su-35 is more capable in air-to-air combat than any fighter in the US or NATO inventories. The only exception to this is the F-22 “Raptor”. Still, while it’s by far the most capable Western fighter in service, there are a number of performance issues with it, affecting its ability to counter the Su-35S in the Middle East or elsewhere.
Perhaps the worst aspect of the F-22A are its extreme maintenance requirements, making it virtually impossible for the fighter jet to fly sorties more than once a week. Also, the Su-35S carries almost twice as much payload as the F-22A, while its supermaneuverability allows it to more easily evade enemy missiles and also have better maneuverability in WVR combat. The aforementioned OLS-35 sensor gives it further advantages in situational awareness while in radio-silence mode. Also, the Su-35S has a much superior maintenance record, being able to fly 3-5 times per day, depending on various conditions and parameters.
The only possible downside that countries like China and Iran might have is the simple fact that Russia exports somewhat downgraded variants of the systems and subsystems I mentioned, meaning that the export version of the Su-35S will be less capable than that used by Russia. Also, the Su-35S has been proven against advanced fighter jets such as the Su-27 and MiG-29 used by the AFU [Armed Forces of Ukraine]. It has been able to shoot down at least four enemy jets simultaneously. On the other hand, the F-22A’s only combat experience against aircraft has been those three unfortunate balloons it shot down over the United States in early February.
– Thank You very much for this incredibly detailed and fascinating insight.
It was a pleasure. Obviously, there’s much more that we could have discussed, but I presume this will be more than enough, for the time being, at least. Best of luck to You and Your respected readership.
Drago Bosnic, independent geopolitical and military analyst