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SUKHOI SU-27IB - FROM FIGHTER TO BOMBER

It comes as no surprise that excellent fighters can be converted into good fighter-bombers ready to attack ground targets. In the 80s the Americans have for instance derived the two seater Boeing F-15E from the Eagle. At the same time the Sukhoi design bureau in Moscow was working on a similar project: The superior Su-27 was taken as a basis to supply a replacement for the Su-24 "Fencer".

General Designer Michail Simonov and his design team lead by Rollan G. Martirosov had a much more radical approach than their western counterparts. After having carried out flight tests - some of which lasted up to 15 hours - with the tandem two-seat Su-30, the entire front fuselage was changed for the Su-27IB (Istrebitel-Bombardirovtschik, i.e. Fighter Bomber), in order to accommodate a "comfort" cockpit with two side-by-side seats. Two crew sit on the well-known Zvezda-K-36DM ejection seats in front of a wide instrument panel consisting of a mixture of analog displays and display screens. They are able to get up and stretch during long flights. There is even a toilet and a small kitchen, where food can be warmed. Thanks to a good pressurised ventilation system there is no need for oxygen masks.

A further characteristic of the Su-27IB is armour plating with a 17mm thick titanium-"tub", which is completed with laminated lining at the sides. The aircraft is entered via a door in the nose wheel bay. Like other Su-27 units the -IB is additionally fitted with small canards. Their task is not only to improve agility, but also to compensate gusts of wind during low altitude flights and thus provide a less tiring environment for the crew.

The airframe of a Su-27UB training fighter was modified in the Sukhoi workshops in Moscow accordingly and flew from the test centre Zhukovski for the first time on 13 May 1990. On the helm of the T10-V1 (No. 42) was pilot Anatoli Ivanov.

The first photo of the "platypus" was in circulation a few months later and showed the aircraft approaching the aircraft carrier "Admiral Kusnetzov", which was cruising in the Black Sea. It caused some confusion. Rumours, which were supported by the Soviets, made out that the new model was a training aircraft for the Russian Navy. It has to be said that the Su-27IB never landed on the carrier.

In February 1992 the picture became a little bit clearer, when the T10V-1 made an appearance during the weapons show arranged for the leaders of the GUS-States in Matschulischtsche (Belarus). The fighter was armed with air-to-surface guided weapons like the Kh-31P, Kh-29L/T and laser guided KAB-500L Bombs. Whether the T10V-1 was ever airborne like this remains doubtful, it seemed to be nothing more than a trial model for the changed aerodynamic configuration.

The first aircraft which was built at the NAPO Works before series production started, the 10V-2 (No. 43) flew for the first time on 18 December 1993 in Novosibirsk with Igor Votintsev an Jewgeni Revunov. It was modified further and received among other things a longer, strengthened landing gear with two nose and main wheels each. The latter are not side by side but behind one another.

The tail boom is now longer and bigger. There is room for a small radar system, which can spot attackers from a distance of about 5km. Two big break parachutes are fitted further to the front between the engines. The tail units are derived from the smaller version of the Su-27 single seater, furthermore the fins below the tail unit have proved to be superfluous.

In March 1994 the T10V-2 flew for the first time non-stop from Novosibirsk to Zhukovski. This is when the Russian press called the aircraft Su-34 for the first time.

After that the T10V-5 (No 45) took off on its maiden flight on 28 December 1994. When it was seen at the Aérosalon in Le Bourget, it caused further confusion, because it was introduced there as Su-32FN. Sukhoi explained that this model was intended for the Navy, and it was fitted with the "Sea Dragon" weapons system, which can detect submarine periscopes at a distance of 150km. It has anti-ship guided weapons and torpedoes on board. It is alleged that negotiations with an export customer are currently taking place.

When the T10V-4 flew for the first time on 26 December 1996, one was finally able to test the weapons systems. A central component is the B004 radar, which was manufactured at the Leninez design bureau in Puschkino near St. Petersburg. It has a fixed aerial with electronic scanning and can track both ground and aerial targets. The drawing up of radar maps and the automatic terrain following flight are possible.

The navigation system consists of a combination of inertial platform and GPS receiver, which gives an accuracy of about one metre. The following systems have been installed for self protection: a Pastel radar warning receiver, the MAK infrared sensor, which can detect approaching missiles, and the Otklik laser warner. Sorptsja-ECM pods can also be carried on board. All systems are interconnected via data bus.

As for the weaponry, the Su-27IB's has 12 stations with a capacity of up to eight tons. A combination of various air-to-ground guided weapons is possible, as is the deployment of heavy anti-ship-guided weapons like Alfa and Moskit. The Kh-65S, a cruise missile with a range of 250 to 280 km, can also be part of the weaponry. There is also a built-in canon and air-to-air guided weapons, which are said to be able to fire backwards as well.

During this year's Aérosalon in Le Bourget, General Designer Michail Simonov explained that ten Su-27IB have already been completed. It is, however, hard to judge how far tests have progressed. The last we heard was that the approval tests, which are mainly carried out in Aktubinsk, will be completed by the end of this or beginning of next year.

In any case, the Su-27IB alias Su-34 seems to be one of the few Russian military aircraft programs which still receives enough government funding. According to Colonel Anatoli Kornukov, Supreme Commander of the Russian Air Force, the fighter-bomber is given a high priority, so is the modernisation of existing fighters.

The reason for this is that the tactical air combat component of the Russian Air Force has only relatively old fighters at its disposal with the Su-24 and Su-25. And there are only relatively few, they make up only 26 to 28 per cent of all Russian fighters. That explains why one is trying to overcome weaknesses in this area.

In view of the dire financial situation it is doubtful whether this will happen quickly or on a big scale. The government finds it hard to finance even the pre-series aircraft, which undoubtedly causes problems to the NAPO Works. Although there is still no export license, Suchoi is definitely interested in foreign customers: A Chinese military delegation was in Nowosibirsk in autumn 1998.

That the Su-27IB's technology has a lot of potential is indisputable. It is planned to substitute the AL-31F engines with the more powerful and economical AL-41F in the series aircraft, which should improve performance. One is also thinking of offering special versions for reconnaissance, (combination of internal side looking radar, infra red sensor and cameras) and electronic warfare.

From FLUG REVUE 8/99, page 54