This Old Flanker

Hi, I’m Bob Villa, and welcome to This Old Fighter. Today, we’ll be looking at a classic late cold war fighter that always impresses on the airshow circuit: the Sukhoi Su-27. NATO reporting name: Flanker.

The Sukhoi Su-27 Flanker is a very interesting fighter. It’s somewhat analogous to an F-15, but since the Soviet Air Force wasn’t big on midair refueling, they designed it to be very large so it could carry enormous quantities of fuel internally. It’s got some phenomenal aerobatic capabilities, but suffers from a general lack of payload for its size and some less than stellar reliability numbers. That said, it’s also cheap, and Russia is an infinitely more loyal and useful friend than America these days. Supposing one were to buy some Zhuravliki1, what would we get in them?

Let’s talk engines first. We’re looking for power in an afterburning turbofan. Best in production is the 142 kN AL-31F1S from Saturn Lyulka. Stretching things a little, the AL-31FM2, currently in testing, can put out 145 kN of thrust with afterburner. We’ll also want 3-D thrust vectoring here, with nozzles that can move in both pitch and yaw directions. Thrust vectoring requires some extra training however, as it can cause the aircraft to bleed energy too quickly. Still, it’s a nice extra edge pioneered on some Flanker models in the 90s.

Now, sensors. The Flanker doesn’t have AESA available just yet, we’re stuck with PESA. But, Rafale also has PESA, and Eurofighter still uses mechanically-scanned arrays. However, the Flanker has a really big nose radome for a large, powerful array. The best radar available is the N0035E Irbis-E, which is mechanically steerable to increase the maximum deflection angle of the beam. It’s got a 20 kW peak power, 5 kW average power, can track 30 targets at ranges of up to 400 km, and can engage 8 simultaneously. Way cool. Even the original Su-27s came with IRST and helmet mounted sights, so no special add-ons are needed here. One of the more interesting features of some late model Flanker prototypes, which we’ll put to use, is the N012 radar in the tail boom between the engines. This has a range of about 60 km for fighter sized targets, and is primarily designed to help warn of approaching rear threats. It’s also used to cue the defensive systems. There’s an improved version available, the Pharaon, which gets about 15 km more range for the “fighter size test target”. We’ll call for the Pharaon aft.

In terms of hardpoints, more is better. More specifically, we’ll go for the extra underwing hardpoints introduced in the 90s. The Russians wanted to facilitate the use of wingtip jamming pods like the Knirti SAP-518. But, those lose the wingtip rails, so Sukhoi added an extra pair of underwing hardpoints to take the short-range AAMs that would normally go on the wingtips. So, our Flankers will have a total of fourteen hardpoints: two wingtip, four under each wing, and four under the fuselage. Two of the underwing hardpoints will be plumbed to permit the installation of drop tanks, for an extra 4,000 L of fuel. We’ll get a pair of SAP-518s with each Flanker courtesy of Rosoboronexport. Why the Knirti pods? Well, since they’re also Russian, we can probably get a deal on the whole package. Plus, they’re some pretty powerful jamming pods, capable of jamming in the 5-18 GHz range. They’re modern, digital radio frequency memory jammers, so they’re better at emulating complex waveforms. Plus, with two pods widely spaced out (wingspan is 14.698 m), we can use crosseye jamming techniques to spoof incoming active-radar guided missiles. While we’re talking self-protection here, we’ll want to include a missile approach warning system (integrated with that snazzy Pharaon), the usual chaff and flare dispensers, and a Kedr2 towed decoy.

Now, let’s talk about aircraft structure. Our Flankers will have canards, to maximize agility. Also, because canards are cool. Some Flankers have opted against canards to reduce weight and radar signature. Our response is that it’s a Flanker. It has an elephantine radar signature and the addition of more control surfaces isn’t going to change that much. We will replace old soviet era hydraulic controls with shiny new quadruplex digital fly-by-wire controls. Since we have a digital flight control system, we can delete the dorsal airbrake to save a little weight, and get the same airbrake effect with differential deflection of the rudders.3 We’ll also reinforce the frame and the landing gear to deal with the increased weight. Our landing gear will be the dual nosewheel type, instead of the single nosewheel of the base model Su-27. Internally, we’re going to use all that space for 11,500 kg of internal fuel. And, of course, we’re going to opt for the midair refueling boom. How could we not?

In the cockpit, we’ll go with the center-stick version of the HOTAS control set. We will also use the conventional throttles; I’m not a big fan of pressure-based controls. The tactile feedback of actually being able to move the controls is nice. Avionicswise, we’re going non-Russian. More specifically, Franco-Israeli. The HUD comes from Israel: the Elbit Su 967, with it’s holographic displays. We’ll use a pair of Thales 12″x9″ (WxH) LCDs to display flight information. We’re not opting for touchscreens here. We prefer the traditional array of buttons around each displays. We don’t think touchscreens are robust enough yet, and prefer the tactile feedback and muscle memory that we can get with physical buttons. The Russian Zvezda zero-zero ejection seats are fine, and we won’t bother to replace them.

That’s it. One awesome Flanker. Since we also have an ego that’s almost as big as Russia, and we like to confuse defense analysts, rather than name this something sensible like Su-35MKB, we’ll insist that it be called Su-374. We might even recycle the old ad copy and call it the Su-37 Terminator.

1.) “Baby Cranes”. Because flankers are cute and adorable and above all small.
2.) Roughly analogous to an ALE-50.
3.) The Super Hornet uses a similar method.
4.) There’s already a Su-37, but that designation was applied to a pair of experimental demonstrator aircraft around the early 2000s. They did not go into production. This one will.

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