The U.S. Federal Aviation Administration (FAA) assigned the Aviation Rulemaking Advisory Committee (ARAC) a task to identify and develop recommendations on additional requirements for low speed alerting in new transport category airplanes.
The action was triggered, amongst others, by the fatal accident involving a DHC-8-400 of Colgan Air in February 2009. All 49 on board were killed when the airplane stalled and crashed while on final approach to Buffalo, NY.
With respect to low speed alerting, the FAA previously revised regulations in the area of flight guidance (autopilot) and performance and handling qualities in icing conditions to improve transport airplane standards for low speed protection (in the case of icing, stall warning standards were enhanced).
ARAC is initially tasked with providing information that will be used to develop standards and guidance material for low speed alerting systems. This information may result in standards that complement existing stall warning requirements. The working group will be expected to provide a report that addresses the following low speed alerting technical questions:
- How much time is needed to alert the crew in order to avoid stall warning or excessive deviation below the intended operating speed?
- What would make the alerting instantly recognizable, clear, and unambiguous to the flightcrew?
- How could nuisance alerts be minimized?
- Could the alerting operate under all operating conditions, configurations, and phases of flight, including icing conditions?
- Could the alerting operate during manual and autoflight?
- Could the system reliability be made consistent with existing regulations and guidance for stall warning systems?
- Are there any regulations or guidance material that might conflict with new standards?
- What recommended guidance material is needed?
- After reviewing airworthiness, safety, cost, and other relevant factors, including recent certification and fleet experience, are there any additional considerations that should be taken into account?
- Is coordination necessary with other harmonization working groups (e.g., Human Factors)? (if yes, coordinate and report on that coordination)