YAK ATTACK
Irkut's Yak-130 is en route to Russia to showcase the skills of a newly integrated national aerospace industry at a global level. But how does it feel to fly the trainer?
PETER COLLINS IRKUTSK
In mid-May, I was given a once-in-a-lifetime opportunity to travel to Irkutsk in eastern Siberia to test-fly and evaluate the Yak-130.
The Yak-130 - the Russian air force's advanced flight and tactical combat trainer - prepares student pilots to fly and fight in the latest frontline fighter and fighter/bomber types, including the RSK MiG-29/35 and Sukhoi's Su-27/30/34/35 series and, in the future, the PAK-FA T-50.
Irkut received its latest firm order for the Yak-130 - 55 aircraft, plus 10 options - from the Russian defence ministry in November 2011. Additionally, the company has already responded to its first export success with the type, having completed delivery of 16 Yak-130s to the Algerian air force last year.
I was honoured to become the first Western test pilot to be invited deep inside Russia to independently carry out such an evaluation. This is a highly significant marker in the desire of Russia's newly integrated aerospace industry to openly compete in the global aviation marketplace and to freely showcase the design, technical, engineering and production skills it possesses.
Opened in 1936 and strategically positioned between Moscow and Vladivostok, the Irkutsk production facility has manufactured more than 6,700 aircraft, including designs from the Antonov, Beriev, Ilyushin, Mikoyan, Petlyakov, Sukhoi, Tupolev, and Yakovlev bureaux.
Irkut, now a fully integrated aerospace company, has its headquarters and design centre in Moscow. It is responsible, by value, for providing more than 30% of Russia's aircraft business revenue and 15% of the nation's arms exports.
The publicly listed company has a $1 billion capitalisation by share and an order portfolio totalling more than $7 billion. With 14,000-plus employees and established links to Russian universities and research and development facilities in Irkutsk and Moscow, it has strong global aerospace potential.
In addition to the Yak-130, other types being produced, completed and upgraded in Irkutsk include the thrust-vectoring Su-30MKI for India - also assembled indigenously in partnership with Hindustan Aeronautics - plus the Su-30MKM for Malaysia, and another version for Algeria.
Such military activities are complemented by the start of production of the civil MS-21 single-aisle airliner, in the 130- to 212-seat class. Its design is led by Irkut, and the aircraft is due for entry into service in 2016. The MS-21 will feature the extensive use of composites for its airframe, along with international collaboration with Western avionics and equipment suppliers. Each month, Irkut also supplies 12 shipsets to Airbus of the fuselage keel section, nose-wheel bay and flap fittings for its A320 family.
A tour around the production facility led by Alexander Veprev, director general of the plant, was impressive. Already vast, and with an additional new production line being constructed for the MS-21, the whole plant was alive with industry and equalled or exceeded in terms of modernity and efficiency anything I have seen in Western Europe.
Overall, the Irkutsk plant gave me the impression of being an aerospace powerhouse, with British, French and German computer-controlled milling and manufacturing machines working day and night to make and finish panels and components from solid ingots of aluminium alloy, titanium and stainless steel.
Su-30MK-series aircraft - with more than 200 delivered from 294 on order for foreign customers - and Yak-130s filled the packed, dedicated parallel facility line-bays. The last of these was in excess of 500m (1,640ft) long and contained more than 20 Yak-130s and 10-plus Su-30s ready to receive engines and avionics. More were parked outside or in the flight-test hangar awaiting ground and flight testing.
It was clear from the tour and a 30min period of cockpit familiarisation inside the hangar that the Yak-130 I was to evaluate is a seriously modern design. The Yak-130's genesis has its roots in a Yakovlev technology demonstrator, originally called the Yak-130D, which was started in 1991 in response to a Russian air force future advanced trainer competition to replace the Aero Vodochody L-39.
Between 1993 and 1999, a joint venture with Italian training specialist Aermacchi continued to develop the aircraft which eventually became both the Alenia Aermacchi M-346 and the Yak-130. Both look similar externally, but the M-346 I evaluated for Flight International in 2006 took the route of Western avionics and engines to become a pure advanced trainer. The Yak-130, by comparison, has become not only a similar advanced trainer but also a true combat trainer.
This has been achieved using open-architecture digital aircraft avionics compliant with a 1553 databus, a full digital glass cockpit, quadruplex-channel digital fly by wire (FBW) with digital channel back-up, and instructor-controlled and variable FBW handling characteristics - to replicate a heavy, medium or light aircraft type - and embedded simulation.
However, the Yak-130 also has nine hard points: two wingtip, six under-wing and one beneath the centre fuselage. It can carry a wide range of modern weapons and other stores, including external wing combat fuel tanks, bombs weighing up to 500kg (1,100lb), TV homing/cockpit-displayed guided bombs, rockets, a twin 23mm gun pod, R-73 infrared-homing air-to-air missiles, and electronic countermeasures pods and chaff and flare dispensers, up to a maximum combat load of 3,000kg.
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The type also has a head-up display (HUD) and a helmet-mounted sighting system (HMSS) with a double GPS/GLONASS receiver updating a laser ring gyro inertial navigation system for highly accurate navigation and precision targeting. This transforms its capability into a highly potent light ground attack/fighter.
Irkut is also proud that the Yak-130 is designed to be part of a new and complete systems-type training approach, which also includes computerised classroom and simulator training devices, in-built and straightforward upgrade and modernisation options for aircraft software/hardware, and an external, computer-controlled and fully networked, integrated logistical support service. The type's life-cycle costs are lower by a factor of four to six than training on two-seat versions of the RSK MiG-29 or Su-27.
This combined approach to training, logistics and delivery is the same as in the West, but Irkut claims its Yak-130 package also has a significant price advantage in comparison with any other advanced jet trainer in its class.
The aircraft is powered by two Ivchenko Progress AI-222-25 full-authority digital engine control powerplants, producing a combined total of 11,000lb (49kN) of thrust and with in-built fire detection and suppression. The same supplier's -28 engine will now be offered, increasing total thrust to 12,300lb.
Normal take-off weight with a full internal fuel load of 1,700kg is 7,250kg, giving a thrust-to-weight ratio of 0.70 with the current -25 engines or 0.77 with the -28 engines. This compares with 0.65 for the BAE Systems Hawk 128 or 0.49 for types such as the Aero Vodochody L-159B.
Maximum fuel capacity with two external combat tanks rises to 2,600kg. True airspeed can reach 572kt/Mach 0.93 and service ceiling is 41,000ft (12,500m). The airframe is stressed to +8/-3g and Yak-130 can sustain a 7g level at a corner speed of 450kt (830km/h) at about 3,000ft, or 6g at 10,000ft.
Typical take-off speed and distance in a clean configuration is 113kt and 550m (1,800ft), with landing figures of 103kt and 750m. Crosswind limit is 30kt. The wing leading-edge slats, take-off/combat flaps and stabiliser trim are all scheduled automatically by the FBW system, with the landing flap and very large top-fuselage airbrake selected by the pilot.
Other features include an on-board oxygen-generating system, an auxiliary power unit for electrical start of the engines, ground cockpit air-conditioning, and emergency airborne electrical power generation.
The Russian aircraft differs from the M-346 by being cleared for unpaved runway operations by using a combination of engine-intake blanking doors that are scheduled by the FBW system on the ground, top-intake openings, large ancillary inlet doors, a trailing link undercarriage and low-pressure tyres.
Additional and smaller top-inlet doors set further aft also open automatically at high angle of attack (AoA) or low airspeeds in response to high-power engine air-intake demands.
The aircraft has automated onboard self-diagnostic test systems to reduce the needs of technical support. The rear-seat instructor pilot, as in the M-346, sits high above the front-seat student pilot, inside a separated but massive bubble canopy. Both crew members are protected by the K-36 zero-zero rocket ejection seat and a command ejection capability. Each canopy top-section is fitted with a miniature detonating cord to shatter the canopy to coincide with seat ejection.
My safety pilot was Yakovlev chief test pilot Oleg Kononenko, recipient of the "Hero of Russia" award - no peer pressure there then. I was to take the front seat and fly the complete sortie in the role of a military assessment pilot. My objective was to try to quantify the breadth of roles the Yak-130 could realistically fulfil across the needs of a 21st century air force.
Our test base was within the Irkut production facility, 12km northwest of Irkutsk city centre, using Runway 14/32 at an elevation of 1,470ft.
Weather on the day was cloud base at 600m, cloud tops at 2,000m, visibility 8km and wind 320/25kt gusting 30kt. QNH was 948hp and outside air temperature 10˚C (50˚F).
Our test aircraft was serial 02 - registered -131 - the Yakovlev engineering test and display aircraft . It is representative of the production standard but carries substantial additional internal test equipment. With 1,600kg of internal fuel and eight wing pylons installed, our all-up weight, including two pilots, was 8,040kg, and the aircraft was to be flown primarily in the FBW "medium aircraft" mode.
My flying clothing was Russian, including an external g-suit and ZSh helmet, which featured the frontal bracket to hold a monocular HMSS, although this was not fitted for the sortie. The cockpit felt wide, comfortable, rugged yet modern, uncluttered and logically laid out, with large buttons that could be operated with a gloved hand and with all switches forward of the 3-9 pilot body line.
The forward cockpit was dominated by three, side by side, 6in x 8in (15cm x 20cm) multifunction display (MFD) electronic screens on the forward console. These support the digital displays of typical flight instruments on the left screen, a tactical situation map/navigation in the centre, and simulated embedded radar, weapons and electronic warfare equipment and aircraft system synoptics on the right. These can be changed by the pilot, however, using menu push buttons.
With this layout, the electronically displayed area of the Yak-130's MFDs is almost twice as large as in the BAE Systems Hawk 128, which uses three 5in x 5in screens.
Above the MFDs was the central up-front data controller (UFDC) and above that, the HUD. At either side of the UFDC were the HMSS detectors for cueing the infrared-homing R-73 missile. As in Alenia Aermacchi's M-346, I liked the twin-engine throttles, which are mounted on horizontal runners on the left cockpit wall, leaving the lower left side of the cockpit console clear for other switch panels.
The hands-on throttle and stick (HOTAS) mimicked the latest MiG-29M2/35 types. The radar, HUD, weapon-select modes and airbrake switches were on the throttles, while weapon triggers and flight mode-connected buttons were on the stick. Although aircraft 02 had a metric Russian digital cockpit displaying altitude in metres and speed in kilometres per hour, Irkut can supply the Yak-130 with a Western digital cockpit showing these in feet and knots, and customise the HOTAS and MFDs to replicate other frontline fighter types. This will be an important selling point for further exports.
Entry to the cockpits for my sortie was via a small ground platform, but the aircraft does feature separate, side-nose-fuselage, fold-out steps for each. After strapping in, I could turn to see the tips of the horizontal stabiliser, so I estimated that my lateral field of view was about 320˚ and therefore ideal for air-to-air combat training. The ejection-seat arm mechanism was simple: with the metal seat handle folded forward and abutting the rear of the central stick, the seat was safe, while hinging it back into the upright position and clear of the stick showed it to be armed.
The canopy is side-hinged to the right, counterbalanced and closed manually for simplicity and robustness. The engine start is electric - we used ground electrical power - and is sequenced automatically through both engines in turn by the selection of only one start switch.
After the start, the engines were held at 85% of N1 for about 90s while the FBW and ancillary aircraft systems were checked via the synoptic pages on the right-hand MFD. With navigation systems loaded, we were ready to taxi about 3min after selecting start. The FBW system automatically scheduled the take-off slats, flaps and trim, an enhanced feature for training and one essential for any fighter that can potentially carry a combination of weapons with such a wide range of weights and dimensions.
Nose-wheel steering, in low mode, is permanently active via the rudder pedals and with the high mode (taxiing only) selected by a button on the throttle. Normal, symmetrical wheel brakes are regulated via a hand-operated vertical lever on the front face of the stick. While this is effective, my preference will always be for rudder pedal-mounted toe brakes. Excess thrust during taxi at this configuration and weight felt high, with the need for regular wheel-brake applications.
On the runway line-up, the aircraft was held on the brakes at 90% N1 and released as the throttles were slammed to the forward stop. The FBW automatic scheduling of the engine-intake inlet doors and top-inlet doors to open on take-off and close on landing is airspeed dependent and completely transparent to the pilot and the delivered thrust.
Acceleration was very brisk, with the rotate started at 190-200km/h (103-108kt) about 12s after brake release and using roughly 800m of take-off roll. After the rotate, the aircraft was immediately pitched up into a 20-25˚ climb, power was reduced to 90% N1 and gear retracted to respect the gear limit of 400km/h. The flaps and slats were scheduled up automatically by the FBW system, with no apparent trim change. The aircraft was levelled at 3,000m and 400km/h.
Above 550km/h, the FBW is a g demand/limit control law, but below this, it blends into an AoA demand/limit control law. However, the transition between these is completely transparent to the pilot and the Russian-designed FBW felt flawless throughout the flight.
Control breakout in any axis was very small and stick centring (using springs) was strong - with a spring-type response, stick-free. Small stick inputs generated a highly accurate aircraft response and control harmony was excellent, with aileron to elevator forces close to the classic 1:2 ratio. In cruise flight with the gear up, rudder-pedal deflection only generated a flat-nose deflection but with no secondary roll effect. The massive, top fuselage-mounted airbrake (out or in) was highly effective and caused little vibration over the vertical fin.
If three channels of the quadruplex system are lost, the FBW will automatically revert to the digital back-up channel, which an instructor pilot can also select for use in training. Even in this mode, the aircraft still felt responsive and accurate in flight, unlike the basic and limited get-you-home system found in earlier-generation FBW fighters.
Quick assessments of the instructor-selected heavy and light aircraft FBW modes made evident changes in stick forces versus the medium-aircraft setting, but were still completely fighter-like in their overall feel.
Back in medium mode at 3,000m, the aircraft decelerated to low speed, wings level and, with the FBW in first-limiter mode, the aircraft was pitched up to limit at 25˚ AoA. This was combined with an audio warning, in English, of "AoA limit". For more advanced training, a second limiter setting of 35˚ is almost double that of many other advanced jet trainers in this category.
In both modes, the Yak-130 features anti-spin protection. We climbed rapidly to 10,000m and with all FBW limiters off, I entered into a two-turn spin to the left from a level entry. The spin mode was very stable in both the pitch and yaw axis and had a moderately low yaw rate. Recovery was instantaneous when I centralised the rudder and pushed the stick forward to around neutral. Pulling out with 4g, I levelled at 6,000m. This was the first time I had ever spun a FBW jet and it felt like a very impressive capability.
Apparent speed stability away from trim was quite strong, but the stick-top electric pitch trim was very rapid to negate out-of-trim forces. At 5,000m, the manoeuvre boundary at 600km/h was buffet limited at about 4.5g. Maximum roll rate was 160˚/s, as specified by the Russian air force, but this can be set much higher if required. Hesitation rolls were very accurate to stop and start at the 90˚ points. From a 550km/h entry speed, a 15˚ AoA loop took 1,700m of altitude to complete, but when maintained at 25˚, took only 1,000m.
In addition to its other FBW safety features, the aircraft has a disorientation button to bring it back to wings-level from nose-high or nose-low situations. Both were highly effective.
Weather conditions prevented us from assessing the air-to-ground weapons modes, but the Yak-130 features an automatic pull-out mode from a dive attack if the aircraft senses danger of ground collision.
Throughout the sortie, I flew the aircraft through the HUD, designed to be common with systems used on most Russian air force MiG-29s and Su-27s. It reminded me, somewhat, of the Panavia Tornado GR1. My only strong recommendation to Irkut, especially when it assesses upgrades for future export, would be to consider fitting the latest-generation wide-angle HUD - one that supports the latest wide display of flight, navigation and weapon symbology - as its potential deserves this.
We recovered to Irkutsk, autopilot connected and HUD directed, for an ILS approach on to Runway 14. The aircraft has the impressive additional capability - as a fighter - to complete an autopilot-coupled ILS autoland. However, as a result of the tailwind conditions, the approach was converted from a low overshoot at 60m into two visual circuits then on to Runway 32, which I flew manually. Downwind speed was 300km/h, base turn 270km/h and final approach 250km/h, transitioning into 10˚ AoA for the final landing.
The pilot-selected final flap setting of 40˚ does cause a small amount of aerodynamic buffet over the horizontal stabiliser, but its effect is minimal. The aircraft was a joy to fly manually in the visual circuit, with accurate, soft touchdowns accomplished with ease. After a sortie lasting little more than 1h, we taxied in and shut down with 450kg of fuel remaining.
The opportunity to evaluate the Yak-130 was a personal revelation and I believe the aerospace industry is coming to the end of a period where aircraft have been subdivided as coming from the West or East. The design, technical and manufacturing skills on show in Irkutsk now equal those of Western Europe, and the far-sighted will embrace the possibilities this represents.
Some aircraft I have flown are good advanced trainers and some are good light-attack aircraft, but the Yak-130 comprehensively covers both roles with sophistication yet robustness, and docility yet potency.
Any air force commander would be delighted to have such a multi-role aircraft in his inventory; in part for the breadth of roles it can fulfil with competence and also because of its affordability and built-in digital future.
Russia has got the Yak-130 almost perfectly right and, for many countries, the training and fighter aircraft could come close to providing a one-type, 21st century air force.
F-link: Vladimir Karnozov, who assisted greatly in arranging this flight test, is our Russia correspondent. Read his work at flightglobal.com/vovick
Source: Flight International
