Let's delve into the details of the Low-Energy Aural Alert (DSC-22_40-30 P ¾). This aural alert system is a critical component in our aircraft design, serving to enhance safety and situational awareness during various flight phases.
Functionality:
The Low-Energy Aural Alert is designed to provide pilots with an auditory warning under specific conditions related to energy state and altitude. Its purpose is to alert the flight crew to potential low-energy situations during critical phases of flight.
Activation Conditions:
- TOGA Selection:
- The aural alert is inhibited when Takeoff/Go-Around (TOGA) mode is selected. This ensures that the alert does not interfere during takeoff or go-around procedures when increased power is expected.
- Altitude Restrictions:
- Below 100 feet Radio Altitude (RA): The alert is inhibited when the aircraft is below 100 feet RA, likely to prevent unnecessary distractions during the crucial low-altitude phase of approach and landing.
- Above 2,000 feet RA: Similarly, the alert is inhibited above 2,000 feet RA, as the aircraft is considered to be in a safer altitude regime.
- Emergency Situations:
- Alpha-Floor Activation: The aural alert is inhibited when the aircraft triggers Alpha-Floor protection, indicating a high angle of attack and potential stall condition. This is to avoid conflicting alerts during critical situations.
- Ground Proximity Warning System (GPWS): The alert is also inhibited when the GPWS is triggered, indicating potential ground proximity issues.
- Flight Control Law:
- In Alternate or Direct Law: The alert is inhibited when the flight control system operates in alternate or direct law. This is likely due to the altered flight control characteristics during these modes.
- Radio Altimeter Failures:
- If both radio altimeters fail: The aural alert is inhibited if both radio altimeters, crucial for accurate altitude measurement, experience a failure. This ensures that false alerts are not generated in the absence of reliable altitude data.
Rationale:
The inhibition criteria are carefully designed to prioritize the most critical phases of flight and prevent unnecessary distractions during normal operations or when other safety systems are actively engaged. This meticulous approach enhances the overall safety and effectiveness of the aircraft, ensuring that the Low-Energy Aural Alert functions precisely when needed most, without causing undue interference in non-critical situations.