Ensuring Safe Operations
Among the operational topics for the technical committee at the triennial ICAO Assembly were significant safety issues. One paper from the Russian delegation provided a description of extensive studies of wake vortices, and the development of a wake vortex safety system that would use outputs from ADS-B, Swim and two Aviation System Block Upgrades 1 elements, with pilot alerts transmitted over the anticipated datalinks in that period–that is, by 2018. The Russian presenter suggested that the uncertainty of wake turbulence today causes unnecessarily large longitudinal approach spacing that could be significantly reduced if real-time wake measurements could be provided to pilots, thereby increasing capacity and airport throughput. Better wake-turbulence forecasting at high cruise altitudes would also allow more flexibility in planning future trajectory operations.
A separate Russian paper discussed training to prevent of loss-of-control accidents stemming from undetected high-altitude stalls caused by icing, IAS failure, incorrect weight entry or lack of angle-of-attack information, particularly during autopilot operation, where the classic symptoms of stick shaker, warning horns and buffet may actually lag the actual stall itself, with the aircraft already descending in a high pitch attitude and possibly rolling. Currently, according to the presenters, even advanced flight simulators cannot adequately simulate high-altitude stalls and are only moderately able to simulate “traditional” lower-altitude ones.