The Su-27M  was  an upgraded variant of the Su-27 ‘Flanker’ incorporating a true air-to-surface capability. Although the capability to carry air-to-surface weapons was added to the baseline Su-27s, it was limited to ‘dumb’ bombs and unguided rockets. The Su-27 fire control system lacked a dedicated ground target acquisition and identification capability. The air-to-air capability would also be improved to restore the balance with the latest F-15 and F-16 fighters and the AIM-120 AMRAAM. The aircraft was later designated Su-35, although Su-27M remains the Russian military designation. 

The Su-35 is equipped with the RLSU-27 radar system. The system is composed of the forward-looking N011 slotted-antenna radar and the small N012 rear-looking radar, the latter is located in the central tailboom. Compared to the N001 radar of the basic Su-27 variants, the RLSU-27 radar offers extended target acquisition range, air-to-surface stand-off attack capability, simultaneous tracking of more targets, surveillance and tracking of targets in the rear hemisphere and improved counter ECM. The new radar is also capable of terrain-mapping, enabling nap-of-the-eartch (NOE) and obstacle avoidance.

The Su-35 features other advancements in its avionics suite compared to the Su-27. Other principal components were the electro-optical sighting/navigation system, communications suite, instrument guidance equipment, new FBW system, IFF and digital computer. The aircraft is equipped with an advanced self-defence suite consisting of new RWR systems, Sorbtsiya ECM pods, and APP-50 chaff/flare dispenser. 

The instrument panel layout was changed to accomodate three high-res multifuction monochrome CRT displays and an improved HUD, reducing the number of old electro-mechanical instruments needed. Later the Su-35 features multifunction colour LCDs. The IRST sensor was moved to the right off the line of symmetry to improve visibility from the cockpit. . 

The new systems enabled the Su-35 to be capable of using modern air launched weapons. The most important in the air-to-air role, is the medium-range active radar homing R-77 (export designation is RVV-AE) air-to-air missile, the Russian equivalent of the AIM-120 AMRAAM. A maximum of 12 of these missiles can be carried or 10 when carrying the ECM pods on its wingtips. The Su-35 can also be armed with the older R-27 semi-active radar, R-27E IR homing medium-range missiles as well as the short-range R-60 and R-73 IR homing missiles.
The armament now also includes guided air-to-surface missiles and bombs. Aside from the unguided rockets already on the basic Su-27’s weapons list, the Su-35 is now also capable of the Kh-29 TV-guided, Kh-31P anti-radiation, and Kh-31A anti-ship missiles.


These new systems and weapons capabilities make the Su-35 a true multi-role fighter. Combined with its large action radius and reasonable price tag, make the Su-35 a good candidate for export. The Su-35 was first shown at Farnborough international air show in 1993. Early attempts included the Su-35 based Su-37MR which was marketed to the United Arab Emirates (UAE), see Su-37 section. After the first series produced Su-35s had been delivered to the Russian Air Force in 1996, development by the Komsomolsk-on-Amur aircraft manufacturing association (KnAAPO) was aimed at meeting the requirements of possible export customers. The new Su-35s would be offered with the AL-31FP TVC engines, which were developed following the successfull Su-37 trials with the first TVC engines, see Su-37 section. The modified Su-35s also feature an open architecture avionics suite incorporating the latest digital computers and display systems. 

 The first KnAAPO-built Su-35UB was shown at the MAKS 2003 and is currently undergoing flight trials, before it can enter series production.
Other plans for further development of the Su-35 include the Su-35BM. The Su-35BM will be an upgraded Su-35 with Al-41F1 engines and improved avionics, including either the Phazotron Sokol or the new NIIP Irbis radar, to be built around a rotatable passive phased array.