31 Juli 2010
Su-35 (photo : knaapo)
Russia is hustling to find export customers for its latest Su-30 model, the Su-35. The Russian Air Force will receive the first of these later this year, and export customers have been promised early delivery. There are few takers so far. There's just too much competition out there, from late model F-15s and F-16s, plus Rafale, Eurofighter and Gripen. The U.S. F-35 is on the way as well.
That said, the Su-35 is an impressive piece of work. It’s pitched as more reliable and durable than past Russian fighters, good for 6,000 flight hours (compared to 2,500-4,000 hours for earlier models). The big selling points are the sensors. There is a phased array radar that can spot large targets (like B-52s or AWACS) at up to 400 kilometers, and an infrared (heat sensing) passive radar with a range of 80 kilometers. The active radar can also track targets on the ground and use smart bombs. The Su-35 is more maneuverable than earlier Su-30 types.
Irbis E radar (photo : Vitaly Kuzmin)
At one point, the Su-35 was touted as competition for the F-22. It isn't. That competition would be the PAK-FA, which had its first flight earlier this year. There are only three prototypes of the Su-35, and one of those crashed last year. The cause was a problem with one of the two engines. Russia had hoped to have the destroyed prototype fly over the May Day parade in Moscow on May 1st. The crash was really bad PR, since one of the consistent shortcomings of Russian warplanes has been the unreliable engines.
Su-35 radar coverage (image : ares)
Two years ago, the Su-35 had its first flight. Progress has been slow. The Su-35 has been in development since the 1990s. At one point, it was called the Su-37, but the name was changed back to Su-35. Since the 1990s, two different Su-35 prototypes were built. There were many disagreements over what direction the development should take, and by the late 1990s, the project was basically suspended for lack of funding.
The Su-35 is a 34 ton fighter that is more maneuverable than the original, 33 ton, Su-27, and has much better electronics. It can cruise at above the speed of sound. It also costs at least fifty percent more than the Su-27. That would be some $60 million (for a barebones model), about what a top-of-the-line F-16 costs. The Su-27 was originally developed to match the F-15, which is larger than the single engine F-16. The larger size of the Su-27/35, allows designers to do a lot more with it in terms of modifications and enhancements. The Su-35 will carry a 30mm autocannon (with 150 rounds) and up to eight tons of munitions, hanging from 12 hard points.
This chart compares graphically the peak power aperture product estimates for the Flanker radars, and the APG-79. The latter is depicted with some provision for growth. Hybrid array technology used in the BARS and Irbis E provide similar total noise figure for the antenna-receiver design to that of AESA designs like the APG-79. Growth JSF APG-81 radars will be similar to the APG-79. Block upgrades to the BARS to convert it into an Irbis E configuration will not present difficulties as the latter is an uprated derivative of the former. (ausairpower)
Russia's effort to develop an F-22 class fighter (the PAK FA) is going to require a lot of work. The prototype, that took its first flight recently, was clearly the basic Su-27 airframe modified to be stealthier. This included changing the shape of the aircraft to be less radar reflective, and providing internal bays for bombs and missiles. But there's much more to do in order to achieve anything close to the stealthiness of the F-22. It took fifteen years for the F-22 to go from initial flight, to entering service. The PAK FA could proceed faster, learning from the F-22 experience (especially if some of the Internet based espionage carried out in the last decade was Russian). But such development speed has not been a Russian characteristic.
Another problem is the engines, which were not ready for the first flight. Older model engines were used, because initial flights are mainly to confirm the basic airworthiness of the airframe. The new engines, also being used in the Su-35, are suffering development problems. The Russians have always had difficulties with their high end military engines, and that tradition continues. Currently, the Russians say it will take several years to perfect the new engine.
T-50 PAK FA (photo : knaapo)
Russia will also need a new family of air-to-air missiles, as the current ones are too large for the internal bays on the PAK FA prototype. These are already in the works, along with more compact versions of air-to-surface missiles. There are also problems with the electronics and, well, you get the picture.