ultimate bad guy? Super Flanker Sukhoi's Su-35, The

Flight Journal, Feb 2001 by Miller, Jay

Sitting on the tarmac at the Zhukovsky flight-test center about 30 miles southeast of Moscow, the Sukhoi Design Bureau's most powerful and capable fighter, the stunning Su-35, gives every impression of it Coiled cobra. Prepared to Strike at the slightest warning it honkers down, nose low, poised on its rough-field Landing gear, peering forward through the single, offset eye of its infrared search-and-track ball.

Currently viewed its the most potent threat to Western military air forces, there is little question that the Su-35 is a superb air-combat platform. Typical of its parent design bureatt's prodticts, it mixes modern technique and technology with a strong (lose of Russian mechanical pragmatism. Sukhoi and the Russian government promote the Su-35 as the chosen standard-bearer fighter of non-western air forces. They explore export opportunities around every international comer. To date, however, no foreign air force has bought a single one.

The reasons are simple: the Su-35 is too big, too expensive and too complex (and it's backed by the questionable goodwill of an unstable, undependable government). Without significant financial and trade offsets-something unlikely to happen-it has little chance of realizing any legitimate international military sales. In a market glutted with American F-16 wannabes, it is sitting at the bottom of a very large pile. It is Russia's extremely capable-but totally unknown-contender.

During a recent trip to Russia, I was privileged to spend three days with the Sukhoi Design Bureau at its ramshackle Zhukovsky flight-test facility on the massive base's northeast side. With hundreds of out-of-service MiGs,

Tupolevs, Antonovs, Mils, Ilyushins and Myasishevs providing a varied backdrop, I observed the awesome Su-35 in action firsthand. While contemplating the big fighter at rest and in the air, it became apparent that I was watching what was conceivably the last of a very long line of highly strung Russian aircraft. Sleek and strong, it represents everything a fighter should be-and everything a fighter pilot would like to fly into combat.

Sukhoi has built fewer than a dozen Su-35s to date. None represent fully operational or production-standard hardware. Rather, each of the prototypes serves as a system, structural, or performance-envelope test bed; and typical of a prototype program, each has been continuously modified since the first Su-35 (initially referred to in prototype form as the T10M, and later, as the Su-27M) arrived at Zhukovsky in 1988.

Cockpit configurations represent some of the most noticeable differences. For instance, four monochromatic (Russia lags behind the West in color-video technology), multifunctional display screens present flight- and weapons-system information to the pilot (virtually standardized in arrangement and presentation symbology in the West) and have been installed in a somewhat random order from aircraft to aircraft. This apparently has been to accommodate everchanging Russian combat requirements and ill-defined ergonomic specifications.

The Su-35 has a "digital quadruplex fly-by-wire flightcontrol system" that makes it comparable, in many respects, to the latest Western standard. This sophisticated approach to flight control permits the pilot-via a complex system of super-high-speed mini-computers-to fly the aircraft at the ragged edge of stability. The computers combine flight-data input from many static pitot sensors, various attitude references and pilot flight-control systems feedback; they then output control-systems actuator data to the horizontal tail surfaces, the ailerons, the rudders and the hyperactive canards. The latter play a key role in virtually all pitch-related maneuvers and can be seen moving almost constantly while the big fighter is in flight. Otherwise, the Su-35 is an amalgam of miscellaneous stock components and materials that can trace their origins back to the 1960s. It is, in many respects, a technological anachronism.

Incorporating older, proven technologies and materials, however, is not a serious flaw but rather an exercise in common sense. For Russian designers, the pragmatics of design far outweigh the Western propensity for state-of-the-art sophistication and complexity at every opportunity.

Arguably one of the finest-looking fighters of the postWW II era, the Su-35 actually represents little in the way of advanced aerodynamic thinking. It is, however, highly maneuverable and surprisingly agile-particularly for an aircraft that has a gross takeoff weight approaching 35 tons. Roll, pitch and instantaneous turn rates throughout most of its 9G envelope are comparable to Western fighters, though it reportedly requires exceptional physical exertion on the part of the pilot to maneuver through an extensive aerobatic repertoire.

The Su-35's air-to-air Phazotron NIIP N-011 multi-mode, look-down/shoot-down radar (which also has an air-to-ground capability out to a range of 124 miles) is sophisticated but not up to state-of-the-art Western standards. Typical of Russian radars, it depends more on its enormous power than on sophistication to accomplish search-andtrack tasks and overcome countermeasures. Regardless, Sukhoi claims the unit can track up to 15 targets simultaneously while it engages any six at ranges of up to 249 miles. Few Russian aircraft observers truly believe the latter, but military strategists often use it anyway for threat analysis purposes.