Angle of Attack Calculator
The Angle of Attack (AoA) is a critical aerodynamic parameter that determines how much lift and drag an aircraft's wing generates. It is defined as the angle between the wing's chord line and the relative wind. This calculator helps you determine the wing's angle of attack based on the aircraft's pitch, flight path, and the wing's fixed incidence angle.
The angle of the aircraft's longitudinal axis (nose) relative to the horizon. Positive for nose-up, negative for nose-down.
The angle of the aircraft's actual trajectory (flight path) relative to the horizon. Positive for climbing, negative for descending.
The fixed angle at which the wing's chord line is mounted relative to the aircraft's longitudinal axis. This is a design parameter.
Calculated Angle of Attack:
Enter values and click 'Calculate'.
Understanding Angle of Attack (AoA)
The Angle of Attack (AoA) is one of the most fundamental concepts in aerodynamics. It is the angle between the chord line of an airfoil (like a wing) and the direction of the relative wind. This angle is crucial because it directly influences the amount of lift and drag produced by the wing.
Why is AoA Important?
- Lift Generation: As AoA increases, lift generally increases up to a certain point, known as the critical angle of attack. Beyond this point, the airflow separates from the wing's upper surface, leading to a rapid loss of lift, a condition known as a stall.
- Drag Production: Drag also increases with AoA. Pilots must manage AoA to achieve an optimal balance between lift and drag for efficient flight.
- Aircraft Performance: AoA affects climb rate, descent rate, airspeed, and fuel efficiency. Maintaining the correct AoA is vital for various flight maneuvers and phases.
- Stall Warning: Many modern aircraft use AoA indicators to provide pilots with a direct measure of how close the wing is to stalling, offering a more reliable warning than airspeed alone.
How is AoA Calculated?
While direct measurement of AoA in flight often involves specialized sensors, it can be estimated or understood through the relationship between several other angles:
- Aircraft Pitch Angle (θ): This is the angle of the aircraft's nose (longitudinal axis) relative to the horizon. A positive pitch means the nose is up, while a negative pitch means the nose is down.
- Flight Path Angle (γ): This is the angle of the aircraft's actual trajectory or velocity vector relative to the horizon. A positive flight path angle indicates a climb, and a negative angle indicates a descent.
- Wing Incidence Angle (i): This is a fixed design angle. It's the angle at which the wing's chord line is permanently attached to the aircraft's fuselage (longitudinal axis). Most wings are mounted with a slight positive incidence to generate lift even when the fuselage is level.
The formula used in this calculator to determine the wing's Angle of Attack (α) is:
Angle of Attack (α) = Aircraft Pitch Angle (θ) + Wing Incidence Angle (i) - Flight Path Angle (γ)
Examples:
- Level Flight: If an aircraft is flying perfectly level (Flight Path Angle = 0°) with a Pitch Angle of 3° and a Wing Incidence Angle of 2°, the AoA would be: 3° + 2° – 0° = 5°.
- Climbing Flight: An aircraft climbing at a 5° Flight Path Angle, with a Pitch Angle of 8° and a Wing Incidence Angle of 2°, would have an AoA of: 8° + 2° – 5° = 5°.
- Descending Flight: An aircraft descending at a -5° Flight Path Angle, with a Pitch Angle of -2° and a Wing Incidence Angle of 2°, would have an AoA of: -2° + 2° – (-5°) = 5°. (Note: Subtracting a negative number is equivalent to adding a positive number).
These examples illustrate how the wing can maintain a consistent angle of attack relative to the airflow, even as the aircraft's orientation and flight path change.