The FAA has consistently emphasized the importance of Angle of Attack (AoA) alerting systems for aviation safety. In its Special Airworthiness Information Bulletin (SAIB: 2024-07), the FAA highlights that AoA indicators significantly enhance situational awareness, assisting pilots in avoiding stalls and loss-of-control incidents. These systems are especially critical during takeoff, landing, and low-speed maneuvers, where the risk of an aerodynamic stall is heightened.
While AoA indicators provide vital safety enhancements, they also pose certain challenges. Their effectiveness relies on precise calibration, appropriate sensor placement, and thorough pilot training. Additionally, variations in display formats and a lack of standardization across different aircraft models have led to concerns regarding usability. Despite these limitations, the FAA strongly advocates for the integration of AoA systems in aircraft, provided they are complemented by adequate pilot training to ensure proper interpretation and utilization.
The Absolute Angle of Attack (Absolute AoA) is a crucial concept in aerodynamics that provides a more accurate measurement of an aircraft’s angle relative to the airflow. Unlike geometric AoA, which varies based on airfoil design, Absolute AoA is a more precise indicator of aerodynamic performance. Cambered airfoils, for instance, generate lift even at zero geometric AoA, making Absolute AoA a more reliable metric for stall prediction and flight efficiency.
Stalls can occur at both low and high speeds, depending on various factors such as airspeed, bank angles, and control inputs. During takeoff and landing, when airspeed is low, pilots must carefully manage AoA to prevent exceeding the critical stall angle. In steep turns, stall speed increases, which can catch pilots off guard if they do not monitor AoA effectively. Similarly, high-speed stalls can result in abrupt loss of control due to excessive elevator input, causing snap rolls and spiral dives.
Aircraft with lower wing loading have reduced stall speeds, while design features such as flaps and slats modify stall characteristics. Flaps increase lift but can lower the stall AoA, whereas slats help maintain lift at higher angles, delaying stalls. Many modern aircraft employ retractable high-lift devices to optimize performance across different flight conditions, balancing lift enhancement with drag reduction.
Conventional AoA systems rely on single-sensor differential pressure measurements, which are often limited to near-stall warnings. These legacy systems are susceptible to inaccuracies caused by changes in weight, loading, and density altitude.
Modern Absolute AoA systems, on the other hand, leverage multi-sensor technology and advanced computational models to deliver real-time AoA data throughout all phases of flight. Unlike older systems that primarily provide stall warnings, new-generation AoA solutions offer continuous feedback for climb, cruise, descent, and landing.
Real-time AoA data throughout all phases of flight
Multiple Digital Display Options – Pilots can choose from various presentation formats, including HUD displays.
Independent Air-Data Integration – Eliminates reliance on pitot-static systems, enhancing accuracy.
Automated Flap and Landing Configuration Adjustments – Utilizing LiDAR and pressure normalization techniques.
Easy Installation – Eliminating the need for long tubes and complex plumbing.
For pilots seeking a more precise and reliable method to monitor AoA, modern Absolute AoA systems provide an unparalleled level of accuracy and situational awareness.
Learn more about the modern Absolute AoA System