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JT-5B screenshot 6.png
JT-5B screenshot 14.png
Type Autogyro
Configuration Fixed gear aircraft, Tricycle landing gear aircraft
Propulsion Single engine aircraft, Pusher aircraft
Manufacturer Jukka Tervamäki
Author(s) Edin Hozic (mr no)
--aircraft= JT-5B
Status Production
 FDM Stars-5.png
 Systems Stars-3.png
 Cockpit Stars-4.png
 Model Stars-4.png
 Website The website for the JT-5B developments.
 Repository The development repository of the JT-5B.
Download Download the JT-5B aircraft package for the current stable release (2020.3).
Forum 'JT-5B' topic on the FlightGear forum.
License GPLv2+

The JT-5B is a homebuilt autogyro, designed and built by Jukka Tervamaki from 1969-1973. Initially developed from the JT-5, the the JT-5B featured a 100mm larger propeller diameter for better efficiency, and a lighter rotor head. The single prototype model was sold to Vittorio Magni in Italy the following year, in 1974. The design was later named 455MT-5 and M-5, with more the modern revision being crowned the Magni M20 Talon. [1]

JT-5B autogyro seconds after liftoff.

Operating Procedures

Note  While the aircraft does not stall, the rotor can slow down and thus should be kept between 450RPM and not exceed 600RPM. The rotor will accelerate with increased back pressure on the stick.
Caution  Avoid sudden input control movements, which can cause Pilot Induced Oscillation (PIO). Flying at zero or negative gravity can induce a Power Pushover (PPO). Prefer controlling pitch with the throttle instead of the stick, as forcing forward pressure can cause induce negative gravity.
Cockpit view of the JT-5B autogyro after takeoff from LOWI.

Engine start

The instrument panel of a JT-5B autogyro.
JT-5B in flight.

In order to start the engine, hold S.


JT-5B autogyro soaring over Honolulu.
  1. Prerotate rotor to 250 RPM (refer to the right-most instrument on the panel).
  2. Release the parking brake using Shift-B.
  3. Add power to accelerate and pull back the stick back by 1/3rd.
  4. Wait to accelerate then add full power
  5. Use the stick to slowly pull up and fly


JT-5B autogyro sitting on the runway at LOWI.
  1. Reduce power to 1/4th.
  2. Wait to slow down - don't force forward pitch.
  3. Upon reaching 40-50kt, pitch down and maintain current airspeed.
  4. Touch down and wait for rotor to slow down somewhat.
  5. Push the stick full back to use rotor and slow down


The information in this section is based on external resources. [1]


Maximum Cruising Speed 140km/h (93mph)
Economy Cruise 120km/h (81mph)
Minimum Speed 40km/h (22mph)
Vne 170km/h (110mph)
Maximum Rate of Climb 590m/s (590fpm)
Service Ceiling (estimated) 4000m (13000ft)
Takeoff Run 80m (230ft)
Landing Run 5m (16ft)
Range 250km (150 miles)
Maximum Disc Loading 7.5kg/sq2 (1.54libs/ft2)
Maximum Power Loading 3.9kg/hp (8.5lb/hp)


Rotor Diameter 7.0m (23ft)
Length 3.55mm (11ft, 5.3in)
Height 2.05m (6ft, 7in)
Fuselage Length 3.5m (11ft 6in)
Wheel Track 1.7m (5ft 7in)
Propeller Diameter 1.2m (4ft)


Horizontal Stabilizer 0.82m2 (8.82ft2)
Vertical Stabilizers 0.73m2 (7.85ft2)
Rudder 0.31m2 (3.3ft2)


Empty Weight 165kg (367lb)
Gross Weight 280kg (622lb)

Power Plant

Engine 1700-2000ccm VW, 70-80HP recommended
Propeller Diameter 1300mm (51.2in)
Pitch Adjust to give 2800-3200RPM.
Static Thrust Requirement Minimum 1300N (290lb)


Rotor RPM Range 380-400RPM
Prerotator 5HP to give 250-300RPM for rotor
Rotorblade Chord 180mm (7in)
Rotor Disk Area 38.5m2 (414ft2)

Rotor brake is included.

External links

  • JT-5B autogyro -Release Current development topic on the FlightGear forum.
  • Jt-5B autogyro Original development topic on the FlightGear forum.
  • The JT-5 Autogyro Description, history and drawings by the original designer. (web archive version as original website is no longer available)