The Agile Threat : Su(khoi)Superagility

      Su-27 Flanker | Su-27UB Trainer Flanker | P-42 Record Flanker | Su-37 Agile Flanker
      Su-27 Flanker A

      Su-27 Flanker A Rendering

      Su-27 Flanker
      Su-27 - single-seat air superiority fighter. The plane has an integral aerodynamic layout, which permitted it to attain high values of lift/drag ratio and lift coefficient along with assuring a considerable increase in the internal fuel reserve and, hence, to do away with the drop fuel tanks. Two AL-31F afterburning bypass turbojet engines, each having a maximum thrust of 12,500 kgf, provide the plane with an excellent thrust-to-weight ratio and agility. The engine air intakes are fitted with mesh guards, preventing the ingress of foreign matter into the engines during landing and take-off. The K-36DM ejector seat allows the crew to escape in emergency irrespective of the aircraft flight altitude and speed, including when it runs on the airfield.

      As an air superiority fighter, the Su-27 is meant to destroy air targets both over friendly territory and 300-400 km away from the line of contact. It can operate in ECM and air defence fire environments, in all weathers, day and night. The aircraft can also destroy ground targets with bombs and missiles. The high combat effectiveness of the Su-27 is assured by:
    1. accurate automatic approach to the desired target;
    2. automatic target search by both a search-and-fire-control radar and its passive optronic tracing system working as an IR locator;
    3. its armament control system comprising a fire control radar, optronic fire control system, helmet-mounted target designator, weapons control system, IFF interrogator, integrated display system;
    4. up to 10 all-aspect medium- and short-range missiles fitted with radar and IR homing heads (R-271, R-27T1, R-73), which is more than carried by any other existing fighter;
    5. mighty GSh-301 fast firing gun with various types of highly effective ammunition ;
    6. high agility displayed at low and medium altitudes and flight speeds allowing the crew to confidently face any air enemy;
    7. possibility of executing a mission and flying back to the home airfield on one engine;
    8. highly effective EW system producing both active and passive jamming signals to impair the functioning of enemy radars (including airborne ones) and missile homing heads;
    9. increased (up to 1,150 km) radius of action with 10 air-to-air missiles, which makes it 1.5
    10. 2 times as great as that of any existing fighter, using for a similar job 1
    11. 2 drop fuel tanks and carrying not more than 6 air-to-air missiles;
    12. distribution of targets among aircraft in a group and execution of concealed missile attack by using target designation received from another aircraft of the group in the scan mode;
    13. highly automated weapons control system and basic equipment;
    14. integrated built-in test and warning system, allowing for the timely registration and indication of the condition of airborne systems in flight and during the preparation of the aircraft for flight. The Su-27 displays high survivability in present day air defence environments owing to:
    15. two-engine power plant scheme with separate fuel supply for each engine located at some distance from the other, thereby ruling out the simultaneous destruction of both with one hit;
    16. good gas-dynamic stability of the power plant, which retains its serviceability even when its gas/air duct is riddled with fragments, bullets, or a shock wave and products of explosion of a missile or shell get into the air intake. The spacing between the fuel tanks and air intake channels precludes the penetration of fuel to the engine inlet from the tanks when these are shot through;
    17. three-spar wing, as well as the special design of the fuselage which allows it to withstand direct hits of bullets and splinters of shells and missiles;
    18. multiple redundancy and spacings between mechanical links of the aircraft control system, which prevent its destruction by one hit;
    19. two independent and mutually duplicating hydraulic systems, whose power supply units and hydraulic pumps are spaced to preclude their simultaneous destruction. With both hydraulic systems inoperative, the aircraft can still be controlled from an emergency power source (hydraulic accumulator);
    20. redundant electrical power supply for services. Should one or two main DC and AC power supplies get damaged, the switchgear will connect the services to a back-up power source;
    21. configuration allowing the airborne equipment and fuselage structure to protect the pilot's cockpit;
    22. robust structure of fuel tanks, resistant to hydraulic shocks and precluding vast damage and a disastrous loss of fuel;
    23. provision of all fuel tanks with a special filler preventing their explosion when they are hit;
    24. active fire control system using special bottles to quench fire in engine nacelles. All the above enables one to conclude that today there is no other aircraft on the world market which could outperform the Su-27 in destroying air targets and gaining air superiority.


      Su-27UB Flanker Trainer


      Su-27UB Flanker Trainer Rendering

      Su-27UB Trainer Flanker
      The most noticeable differences of Su-27UB are:
      • two-seat(2,3) cockpit
      • simpler avionics, which has visible appearance as a missing IR(1) sight.
      • larger tail planes(4)
      There also is a two-seat attacker version, the SU-27IB, with side-by-side seating in a reshaped nose.
      Su-27UB Flanker Trainer Diagram


      P-42 Record Flanker


      P-42 Record Flanker Rendering

      P-42 Record Flanker
      A stripped version of the Su-27, without armament or electronics, used to set time-to-height records.
      Accordingly, one of the T-10S prototypes was stripped of all armament, radar and operational equipment, the fin tips were removed, as was the tailboom and the wingtip launch rails. Even the radome was replaced by a lighter metal fairing. Stripped of paint, the aircraft was polished and all drag-producing gaps and joints were sealed. The engines were modified to give an increase in thrust of 2,204lbs - giving the P-42, as the modified aircraft was designated, a phenomenal thrust-to-weight ratio of almost 2:1.
      The mainwheel brakes could not hold the aircraft at full thrust so the P-42 was anchored to a tracked armoured vehicle by a steel hawser with an electronic lock. With the engines wound up to full power, the hawser was released and the P-42 leaped into the air and climbed at an optimum angle to altitude.
      Between 1986 and 1988 the P-42, piloted variously by Victor Pugachev, Nikolai Sadovnikov, Oleg Tsoi and Yevgeni Frolov, took no less than 27 records from the Streak Eagle, including time-to-height records for 3000, 6000, 9000, 12000 and 15000 metres, a height record of 19335m (63435 ft) and time-to-height records with various payloads. The aircraft even set records for STOL aircraft with a take-off run of less than 1540ft ! Most of these records still stand to this day. Following list is an extarct from official data, posted on FAI site:
      Sub-class C-1h (Take-off weight 12000 to less than 16000 kg)
      Group 3 (Jet engines)

      Type of record Performance Pilot Date
      Time to climb to a height of 3000 m 25s Victor G. PUGACHEV 27/10/1986
      Time to climb to a height of 6000 m 37s Victor G. PUGACHEV 15/11/1986
      Time to climb to a height of 9000 m 44s Nikolai SADOVNIKOV 10/03/1987
      Time to climb to a height of 12000 m 55s Nikolai SADOVNIKOV 10/03/1987
      Time to climb to 3000 m with 1000 kg payload 28s Oleg TSOY 17/05/1988
      Time to climb to 6000 m with 1000 kg payload 38s Oleg TSOY 19/04/1988
      Time to climb to 9000 m with 1000 kg payload 48s Oleg TSOY 17/05/1988
      Time to climb to 12000 m with 1000 kg payload 59s Oleg TSOY 17/05/1988

      Sub-class C-1i (Take-off weight 16000 to less than 20000 kg)
      Group 3 (Jet engines)

      Type of record Performance Pilot Date
      Altitude with 1000 kg payload 22250 m Victor G. PUGACHEV 20/05/1993
      Greatest mass carried to a height of 15000 m 1015 kg Victor G. PUGACHEV 20/05/1993
      Time to climb to 15000 m with 1000 kg payload 2mn 6s Victor G. PUGACHEV 20/05/1993
      Time to climb to a height of 15000 m 2mn 6s Victor G. PUGACHEV 20/05/1993

      Class N / Group 3 : Jet engine

      Type of record Performance Pilot Date of record
      Altitude in horizontal flight without payload 19335 m Nikolai SADOVNIKOV 10/06/1987
      Time to climb to a height of 3000 m 26s Nikolai SADOVNIKOV 11/04/1987
      Time to climb to a height of 6000 m 37s E. I. FROLOV 31/03/1988
      Time to climb to a height of 9000 m 47s E. I. FROLOV 31/03/1988
      Time to climb to a height of 12000 m 58s Nikolai SADOVNIKOV 11/03/1987
      Time to climb to a height of 15000 m 1mn 16s Nikolai SADOVNIKOV 11/03/1987
      Time to climb to 3000 m with 1000 kg payload 28s Oleg TSOY 17/05/1988
      Time to climb to 6000 m with 1000 kg payload 38s Oleg TSOY 19/04/1988
      Time to climb to 9000 m with 1000 kg payload 48s Oleg TSOY 17/05/1988
      Time to climb to 12000 m with 1000 kg payload 59s Oleg TSOY 17/05/1988

      Sub-class C-1 (Unlimited take-off weight)
      Group 3 (Jet engines)

      Type of record Performance Pilot Date of record
      Time to climb to a height of 3000 m 25.37s Victor G. PUGACHEV 27/10/1986
      Time to climb to a height of 6000 m 37.05s Victor G. PUGACHEV 15/11/1986
      Time to climb to a height of 9000 m 44.18s Nikolai SADOVNIKOV 10/03/1987
      Time to climb to a height of 12000 m 55.54s Nikolai SADOVNIKOV 10/03/1987

      The visual differences from the basic Su-27
      • Radome was replaced by a lighter metal fairing(1)
      • No avionics, most of outside elements, like IR sight(2) are removed
      • Non-adjustable engine intakes(3)
      • Reduced tail-planes(4) Reduced
      • The fin tips were removed(5)
      • Missing tail-cone(6)
      P-42


      25. Su-37 Agile Flanker


      Su-37 Agile Flanker Rendering

      Su-37 Superagile Flanker
      The new multirole all-weather superagile fighter Su-37 (registration number 711) with full thrust vector control (TVC) represents a logical step forward in the steady implementation by the Sukhoi EDB of a development program of fourth and fifth generation of tactical aircraft from the basic Su-27 fighter for the Russian Air Force. As announced by General Designer Mikhail Simonov, the new fighter is related to "the fourth with two pluses" generation. This is the latest, although far from the last, Sukhoi's development.

      The first flight of the Su-37 prototype was on April 2, 1996, with test pilot Yevgeny Frolov, Hero of Russia, at the controls. This was followed five months later by a demonstration flight of this aircraft at the prestigious Farnborough '96 air show, where it amazed the spectators with its maneuverability. Introducing the new machine, Mikhail Simonov emphasized that, unlike the American X-31, this was no experimental specimen, but rather a prototype of the series production aircraft. It has a standard configuration of the Su-35 multirole fighter, can carry up to 14 air-to-air missiles and up to 8,000 kg of ordnance. The following features clearly set this aircraft apart from the others: The Su-37's powerplant comprises two experimental TVC turbofans, type AL-31FU. The engine was developed by the Lulka-Saturn company team, led by General Designer Victor Chepkin, and is a derivative of the twin-shaft AL-31F turbofan installed on the Su-27. It has a modular design, which allows for replacement of its nozzle, afterburner, mixer, low-pressure (LP) turbine and compressor, and gearbox as part of its post-warranty servicing. One can also repair or replace the blades of the first stage of the LP compressor and all stages of the HP compressor. The axis-symmetric swivelling nozzle is secured to the annular swivel and can be moved in the pitch plane with the aid of two pairs of hydraulic jacks.

      Depending on a maneuver to be performed, the nozzles can be deflected both synchronously and differentially. The biggest problem with the implementation of the TVC nozzle concept, that has still not be resolved by the Americans, was to provide the nozzle reversal joint with a seal strong enough to prevent outblast of the gases with a temperature of almost 2,000 oC and pressure of 5 to 7 kgf/cm2. The AL-31F and AL-31FU engines are fully interchangeable; in other words, all the derivatives of the Su-27 and the base aircraft may be powered by the AL-31FU engine. As well as powering the Su-37 fighter, the AL-31FU engine will be first installed on the Su-30MK multirole two-seater fighter.

      The Su-37 uses the 'unstable integral triplane' layout, which, in combination with the small specific load acting on the wing, high power-to-weight ratio, integral electrical remote control system and powerplant TVC feature, ensures the aircraft superagility, increased range of controlled flight and improved takeoff and landing characteristics. The TVC feature incorporated into the aircraft flight control loop makes it possible to minimize, when required, the flight speed and perform aerobatics at speeds nearing zero without angle-of-attack limitations (hence superagility).

      According to Mikhail Simonov, the aircraft has virtually no angle-of-attack limitations. It can fly flatwise to the air stream, with its tail forward, i. e., with 90 and even 180 deg angles of attack. It can locate targets with its radars and attack them with its weapons from any position. This feature is extremely important for both air combat and the evasion of enemy missile attacks.

      Su-37 is furnished with the full range of onboard systems and equipment, and is a prototype of the series production aircraft. Its avionics equipment comprises an onboard multifunction jamproof forward-looking phased-array radar that can track up to 15 targets at a time, provide target designation, launch and guide several air-to-air missiles fitted with active, passive and IR homing heads, and an optronic fire control and surveillance system. In addition, the onboard avionics equipment is used for mapping, multichannel employment of guided weapons and low altitude flight with avoidance of ground features.

      The information and control facilities in the pilot's cockpit cover four wide liquid-crystal displays of tactical and flight-navigation data, onboard system monitors and an operating conditions control panel. Information from individual systems may be presented on any display selected by the pilot. One more widescope indicator is installed on the windscreen.

      The side short-travel control stick of the aircraft, avionics control handle and strain-gauging engine thrust controls, as well as tactical situation, flight conditions and systems monitors enable the pilot to effectively control the aircraft, systems and weapons.

      The Su-37 multifunction fighter can carry air-to-air and air-to-surface weapons at its 12 hardpoints. For air combat, the aircraft is fitted with R-73E short-range air-to-air IR homing missiles and RVV-AE air-to-air missiles with active radar guidance. To attack ground and water-surface targets, the Su-37 can carry IR and radar homing missiles.

      In the opinion of leading western experts, the Su-37 fighter will stay unrivaled for many years to come and take a deserving position on the world arms market.
      The visual differences from basic Su-27(red marks) and predecessor -Su35(green marks): Su-37 Agile Flanker Diagram

      superagility
      This flying display sequence appeared in one of the Sukhoi's flyers which I was kindly provided by their staff at booth 2E15. This scheme does not fully show the exact routine flown by Su-37 at Paris'97, but closely matches first half. The super Flanker flew slightly extended sequence in which few elements were shuffled. For example the tail slide (16) was replaced with very tight loop and Hook (horizontal Cobra ) was added.

      Both Saturday and Sunday performances (June 21st and 22nd) are available in MPEG format. Clicking on the individual element listed in the right column will download this particular part of the Su-37 display. Note that some elements are grouped so that a single clip contain several elements.

      Flown by Evgueni Frolov (Sukhoi's spelling), Su-37 put on most marvelous display I have ever seen and was the only one to trigger applause. Not even Rafale was greeted so enthusiastically by (mostly French) public.

      On Sunday, June 22nd, full display routine was not flown because pilot was not able to retract aircraft landing gear. However Frolov carried out very impressive climb (1), vertical roll (2), 3/4 loop (3) followed by Cobra (4) with landing gear extended!!! Only after this he cancelled the rest of the display to a great disappointment of the spectators.

      This unfortunate mishap will certainly cause a slight damage to hard to beat Su-37 image. Within hours French TV made a comment on Sukhoi team unable "do things right" and pointed out "obvious" superiority of Rafale. What they failed to notice, however, is that none of other fighters managed to came close to Su-37 display with gear down or up.

      Curiously, the video shown at Sukhoi booth clearly depicted Su-37 doing double Somersault (aka Kulbit). This maneuver was performed at higher altitude than "plain" airshow version.
        1. Take-off.
        2. Half vertical roll.
        3. 3/4 loop.
        4. "Pougatchev Cobra".
        5. Heading reversal 90ox270o with descend.
        6. Half loop.
        7. "Pougatchev Cobra" with turn.
        8. Flight at 450 pitch with 90o turn.
        9. 1 1/2 roll.
        10. Turn with reheat.
        11. Fixed roll.
        12. Half loop.
        13. Somersault (Loop with min radius).
        14. Heading reversal 90ox270o.
        15. Flight at Vmin
        16. Tail slide.
        17. Rolls.
        18. Heading reversal 90ox270o and landing.
      display

      Last modified on: Monday, April 10, 2000.