Aircraft Roll Rate Calculator
Estimate aerodynamic roll performance based on helix angle geometry.
Enter speed in Knots (KTAS).
Total span in Feet (ft).
Custom Helix Coefficient
Heavy Transport / Airliner
General Aviation (Trainer)
High Performance / Fighter
Aerobatic Aircraft
Select a type to auto-fill the coefficient below.
Non-dimensional roll parameter.
Performance Estimation
Estimated Roll Rate:
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Roll Rate (Radians):
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Time to Bank 360°:
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Tip Velocity:
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Understanding Aircraft Roll Rate Calculations
The roll rate of an aircraft, typically measured in degrees per second, is a critical performance metric defining maneuverability. Unlike simple turn rates, roll rate determines how quickly an aircraft can transition from level flight to a banked turn or reverse a turn direction.
The Helix Angle Method
This calculator uses the Helix Angle (pb/2V) approximation. This is a non-dimensional aerodynamic parameter that relates the wingtip's spiral path through the air to the aircraft's forward speed. The formula used is:
p = (2 × V × Helix_Coefficient) / b
- p: Roll rate in radians per second.
- V: True Airspeed (TAS).
- b: Wingspan.
Typical Values
Different categories of aircraft have distinct helix angle coefficients due to their aileron size, wing stiffness, and aerodynamic design:
- Transports/Airliners (0.01 – 0.03): Designed for stability, resulting in slow roll rates (15-30 deg/s).
- General Aviation (0.04 – 0.06): Standard trainers like a Cessna 172 usually fall in this range (30-60 deg/s).
- Fighters (0.07 – 0.09): High-performance military jets designed for combat maneuvering (150-250+ deg/s).
- Aerobatic (0.10+): Specialized aircraft like the Extra 300 designed for extreme roll performance (360-400+ deg/s).
Physics Limitations
While this calculator provides a geometric estimation, real-world roll rate is also limited by aeroelasticity (wing twisting), adverse yaw, and the physical strength of the pilot to deflect control surfaces at high speeds. As speed increases, the dynamic pressure on the ailerons makes them harder to move, potentially reducing the roll rate despite the theoretical increase in the formula.