General Aircraft Information

The L-29 aircraft is a two-seat, single-engine jet aircraft designed for basic and advanced pilot training.

Brief Aircraft Characteristics

  • Flight training on this aircraft can be performed from concrete, grass, or sand runways. Takeoffs and landings on compacted snow cover, including partially icy runways, are possible but with increased caution.

    The aircraft is equipped with an M-701c500 engine with a radial compressor and a single-stage gas turbine.

    The aircraft allows for advanced aerobatic maneuvers, e.g., loops, rolls, spins, stalls, and other VTP elements across the entire speed range, while the aircraft's control, stability, and maneuverability are fully satisfactory during maneuvers. The aircraft recovers easily from a spin. It has sufficient equipment to allow flying day and night in adverse weather conditions.

  • Good visibility from the cockpit, automatic cabin pressure and temperature control, and instrument layout in the cockpit create sufficiently comfortable conditions for pilot work.

    Aircraft maintenance in operation is simple, so both flying and engineering-technical personnel can easily handle it.

Basic Structural Characteristics of the Aircraft

The L-29 Delfin is a two-seat jet aircraft with a fixed all-metal construction, mid-wing, and retractable landing gear, designed for pilot training.

  • Cockpit

    The cockpit is pressurized and divided into two separate sections – the front for the student and the rear for the instructor. For solo flights, piloting is exclusively from the front section. Both sections are equipped with identical controls and instruments.
  • Fuel System

    The L-29 has two fuselage tanks with capacities of 670 and 360 liters. Two additional tanks of 150 liters each can be attached under the wings. The maximum fuel capacity is 1,330 liters. Consumption depends on flight mode and load.
  • Controls

    The control of the elevator, rudder, and ailerons is purely mechanical, without hydraulic boosters – directly via pushrods. The pilot has a direct connection to the control surfaces, which ensures precise response.
  • Hydraulic System

    The hydraulics control the landing gear, flaps, and speed brakes. The system has a main and an emergency circuit, with the emergency circuit allowing one extension of the landing gear and flaps. Operating pressure is 110 atm and is monitored in both pilot compartments.
  • Landing Gear and Flaps

    The tricycle landing gear is fully retractable and hydraulically operated. The nose gear retracts forward into the fuselage, the main gear into the wings. The landing flaps are extendable to three positions (takeoff, flight, landing) and automatically retract at a speed of 290 ±10 km/h.

    Stabilizer

    From the third production series, the aircraft is equipped with automatic stabilizer adjustment according to flap position. This reduces the forces required on the control stick and increases piloting comfort when changing flight mode.
  • Air System

    Air is used for wheel braking, cabin sealing, and emergency jettison of cabin canopies during ejection. The system also includes air cylinders and electromagnetic valves activated in emergency situations. The air system is divided into a main and an emergency circuit to ensure.

    Oxygen and G-Suit Equipment

    For flights above 4000 m, an oxygen mask must be used. The L-29 is equipped with an anti-G system, an automatic AD-5 regulator, and the possibility of using high-altitude compensating suits (PPK-1, VKK-2/3/4).
  • Radio and Navigation Equipment

    Modern equipment includes:
    - Becker RT6201 (COM 1)
    - Garmin GNC 255A (COM 2, VOR/ILS)
    - Audio panel GMA 340
    - Transponder Garmin GTX 330 (mode S)
    - 2x GPS Garmin Aera 550
    - Emergency Locator Transmitter (ELT) AK-451-2-D
  • Main Aircraft and Engine Data

    • Aircraft

      • Wingspan: 10.3 m
      • Length: 10.8 m
      • Height: 3.1 m
      • Wing area: 19.8 m2
      • Empty weight of L-29 aircraft: 2364 kg
      • Normal takeoff weight of L-29 aircraft: 3324 kg
      • Maximum takeoff weight of L-29 aircraft: 3586 kg
      • Flap area: 2.77 m2
      • Aileron deflection: + / – 15°
      • Horizontal tail span: 3.34 m
      • Horizontal tail area: 3.31 m2
      • Elevator deflection
        • Up: 32° +/- 1°
        • Down: 18° +/- 1
      • Trim tab deflection
        • Up: 11° +/- 1°
        • Down: 20° +/- 1°
      • Stabilizer deflection at flap position:
        • -0° : -0°,15 “+/- 5”
        • -15° : -1°,40′ + 40′ – 15′
        • -30° : -3°,40′ +/- 10
      • Vertical tail area: 2034 m2
      • Vertical tail sweep angle: 37.5°
      • Rudder deflection: 25° +/- 1°
      • Tire pressure
        • Front: 2.2 + 0.5 kp/cm2
        • Main: 5.5 + 0.5 kp/cm2
    • Engine

      • Engine type: M-701c500
      • Rotor rotation direction: Left-hand in flight direction
      • Compressor pressure ratio at n = 100%: 4.34
      • Air mass flow at n = 100%: 16.7 kg/s
      • Fuel: JET A1
      • Oil: SHELL ASTO 3SP, MK – 8p, MS – 8p
      • Calculated engine thrust at n = 100%: 890 – 40 kp
      • Dry engine weight: 355 kg + 2.5%
      • Maximum engine diameter: 889 mm
      • Maximum engine height: 980 mm
      • Engine length mounting flange – extension pipe: 1848 mm
      • Total engine length: 2113 mm
      • Compressor: Centrifugal, single-stage with single-sided inlet
      • Number and type of combustion chambers: 7 – tubular

    Aircraft Takeoff and Landing Characteristics

    • Aircraft Takeoff Characteristics

      Conditions: takeoff from concrete runway, landing flaps extended to 15°, maximum engine RPM

      • Aircraft takeoff weight: 3550 kg / 3280 kg
      • Takeoff roll distance to lift-off: 740 m / 600 m
      • Distance from lift-off to H = 25 m: 630 m / 500 m
      • Takeoff roll time to lift-off: 31.3 s / 25 s
      • Climb time from lift-off to H = 25 m: 15.1 s / 12.1 s
      • Total takeoff time to H = 25m: 46.4 s / 37.1 s
      • Liftoff speed: 170 km/h – 160 km/h
    • Aircraft Landing Characteristics

      Conditions: dry concrete landing area, intensive braking, flaps extended to 30°

      Note: When landing on a grassy area or an area covered with uncompacted snow, the rollout distance is shortened. When landing on a wet or icy surface, the rollout distance is extended because it is not possible to use the brakes to their full extent. The stated takeoff and landing characteristics apply to MSA conditions (p = 760 mmHg, t = 15°C) and no wind. The takeoff and landing characteristics of individual aircraft series are practically indistinguishable.

      • Landing flight path length: 520 m
      • Rollout distance: 480 m
      • Total landing distance from H = 25 m: 1000 m
      • Gliding speed before landing: 180 km/h
      • Touchdown speed: 145 km/h
      • Landing weight: 3240 kg

    Flight Restrictions

    • Without External Loads

      Maximum speed:
      – Aircraft Series 4 and above – 800 km/h (up to 1900 m altitude)

      Maximum Mach number:
      – Aircraft Series 4 and above – M 0.75 (at 1900 m)

      Maximum load factor:
      – –4 g to +8 g (all series)

      Static ceiling:
      – 10,600 m (all series)

      Note: The maximum permitted flight altitude is 7000 m. Above this altitude, stable engine operation is not guaranteed.

    • With External Loads

      Maximum speed:
      – Aircraft Series 4 and above – 800 km/h (up to 1900 m altitude)

      Maximum Mach number:
      – Aircraft Series 4 and above – M 0.75 (at 1900 m)

      Maximum load factor:
      – –4 g to +8 g (all series)

      Static ceiling:
      – 10,600 m (all series)

      Note: The maximum permitted flight altitude is 7000 m. Above this altitude, stable engine operation is not guaranteed.

    • General Restrictions (all Series)

      Max. landing gear extension speed: 290 km/h

      Max. flap extension speed: 270 km/h

      Max. crosswind during takeoff and landing: 12 m/s

      Flight with a single pilot is permitted only from the front cockpit.

      Inverted flight:
      – Maximum 15 seconds continuously
      – Repeated flight possible after 30 seconds of horizontal flight (needed to replenish fuel in the inverted flight tank)
      – If oil pressure drops below 1.2 kp/cm² and does not increase in horizontal flight, landing is required within 10 minutes.

    • Highest Permitted Speeds During Ground Braking (According to Fuel Quantity)

      • 1300 l: 140 km/h
      • 1000 l: 145 km/h
      • 700 l: 150 km/h
      • 400 l: 160 km/h

    Main Operating Modes of the M-701c500 Engine

    • Ground Idle

      • RPM: 35 – 39 %
      • Exhaust gas temperature: max. 550°C
      • Oil pressure: min. 0.5 kp/cm2
      • Engine run time: 10 min
    • Idle at H = 1000 M

      • RPM: 74.8 %
      • Exhaust gas temperature: max. 550°C
      • Oil pressure: min. 0.5 kp/cm2
      • Engine run time: unlimited
    • Cruise Mode

      • RPM: 94 %
      • Exhaust gas temperature: 600°C
      • Oil pressure: 1.8 – 2.5 kp/cm2
      • Engine run time: unlimited
    • Normal Mode

      • RPM: 97 %
      • Exhaust gas temperature: 635°C
      • Oil pressure: 1.8 – 2.5 kp/cm2
      • Engine run time: unlimited
    • Maximum Mode

      • RPM: 100 % + 0.5 – 1.3
      • Exhaust gas temperature: Hp < 5 km – 700°C
      • Exhaust gas temperature: Hp <= 6 km – 705°C
      • Exhaust gas temperature: Hp <= 8 km – 705 °C
      • Exhaust gas temperature: Hp <= 10 km – 715°C
      • Oil pressure: 1.8 – 2.5 kp/cm2
      • Oil temperature: max. 110 °C
      • Engine run time:
        • On ground: 2 min
        • In flight: 6 min
    • Acceleration

      • POM adjustment from idle to maximum: 1 – 2 s
      • Exhaust gas temperature: 730°C
      • Acceleration time:
        • On ground: max. 12 s
        • Up to Hp = 5 km: 14 s
        • above Hp = 5 km: 18 s
      • Permitted overshoots: 5 overshoots with max. overshoot up to 101.5 % (15,630 rpm)