GÖKBEY Rotor System & Airframe Design: 13.20 m Main Rotor, Tail Rotor and Composite Body
Two features shape a helicopter’s flying character above all others: the rotating-wing system (the rotor) and the airframe that carries it. On the GÖKBEY (T625) utility helicopter, that pair is built around a 13.20-metre main rotor and a composite-heavy airframe. The aim is adequate lift in the 6-tonne class, low vibration and a long-lived structure.
Main rotor: 13.20 m diameter, composite blades
The main rotor that generates the GÖKBEY’s lift has a diameter of 13.20 metres. Its blades are made from composite material, which resists fatigue better than metal and is more damage-tolerant. A composite blade does not fail catastrophically the instant it is damaged at one point, an attribute that matters for both safety and maintenance cost. The blades are shaped aerodynamically to cut vibration and noise.
Rotor hub and vibration management
The rotor hub that ties the blades to the main shaft is one of a helicopter’s most heavily loaded mechanical areas. Modern hub designs aim to reduce the number of hinges, cutting maintenance needs and limiting vibration at its source. Low vibration directly affects both crew comfort and the service life of the avionics and airframe.
Tail rotor and anti-torque
To counter the torque that tries to spin the fuselage the opposite way as the main rotor turns, the GÖKBEY uses an anti-torque (tail) rotor at the tail. The tail rotor also steers the helicopter about its yaw axis. This classic main-rotor-plus-tail-rotor layout is a common, mature solution in 6-tonne-class utility helicopters.
Composite airframe and structural philosophy
The GÖKBEY’s airframe is made largely of composite materials, with metal reinforcement in critical load areas. Because a composite structure delivers the same strength at lower weight, it adds to payload and range. It also resists corrosion, an important advantage in maritime and humid-environment missions.
A crashworthy design
The airframe and rotor system are designed not only for flight performance but also for crashworthiness. The primary structure is shaped to absorb energy in a hard landing, and critical components are meant to behave predictably under impact. This safety dimension of the rotor and airframe is what makes it feasible to use the same platform in higher-risk roles such as air ambulance and search and rescue.
Some detailed numerical figures for the rotor, airframe and structural-material ratios have not been released item by item by the manufacturer. The values here rest on publicly announced general data; the final production configuration can vary by customer and variant.
Modular structure and variant fit
The ability of the same rotor and airframe skeleton to carry different mission equipment is a result of the GÖKBEY’s modular design approach. Standardising the cabin layout and structural attachment points makes it easier to derive variants — from transport to maritime roles — from the same base structure.
Frequently Asked Questions
What is the GÖKBEY’s main rotor diameter? The main rotor diameter is 13.20 metres.
What are the rotor blades made of? The blades are made from composite material with high fatigue and damage tolerance.
Does the GÖKBEY have a tail rotor? Yes. It uses an anti-torque tail rotor that balances torque and provides yaw control.
Why is the airframe composite? A composite structure offers high strength at low weight plus corrosion resistance, which adds to payload and service life.
Is the airframe designed for crashworthiness? Yes. The primary structure is shaped to absorb energy in hard landings and to protect critical components.
