SAFO Calls For A Constant Angle Of Descent For Night IFR

The FAA has issued a Safety Alert For Operators (SAFO) for Parts 121 and 135 Operators using Constant Angle of Descents techniques for nonprecision approaches.  The alert was written after an operator conducting a nonprecision approach at night in instrument meteorological conditions (IMC) conditions failed to control their descent rate while conducting the approach procedure resulting in the airplane crashing short of the runway.

According to the official FAA document:

"During a nonprecision approach procedure, the descent from the final approach altitude to the minimum descent altitude (MDA) requires disciplined piloting technique and increased situational awareness to accommodate the pilot workload during this segment of the approach. As the complexity of the approach procedure increases, such as multiple step-down fixes or a circling approach, the pilot’s workload increases. Environmental concerns such as night operations and weather conditions at minimums provide a cumulative affect on pilot workload. The workload under the aforementioned conditions increases significantly for part 135 single pilot operations. Therefore, operators should evaluate and, if necessary, implement appropriate procedures to reduce workload issues applicable to nonprecision approaches.

Such procedures should include the use of vertical navigation (VNAV) (if equipped) during nonprecision approaches, as a means to achieve a constant angle of descent approach profile from the final approach fix (FAF) to MDA. If the airplane is not VNAV equipped, the operator should develop procedures that address approach profile techniques using a stabilized constant angle of descent from the FAF to arrive at the published MDA prior to the published visual descent point (VDP). If the approach does not have a published VDP, the flightcrew may determine a point along the course between the FAF and missed approach point that would be appropriate for a VDP. With the runway environment in sight, and at the published VDP or established on glidepath by means of a visual landing aid or vertical guidance (VNAV equipped), the flightcrew may begin a normal descent from MDA to the landing runway.

Operators should place a strong emphasis in their procedures relative to altitude management throughout the approach procedure. Particular attention should focus on methods and procedures established for use by the flight crew to manage their descent and maintain published altitudes along with appropriate descents from altitudes to either the next altitude or the landing runway, as appropriate."

The FAA recommends that Part 121 Directors of Safety and Directors of Operations, part 135 Directors of Operations, and Training Managers should perform a thorough review of their General Operations Manual (GOM) and training program to evaluate and, if necessary, develop and implement procedures for the use of constant angle descent techniques during nonprecision approach procedures. The use of constant angle of descents techniques should be a focal point during all flightcrew training, testing and checking.

FMI: www.faa.gov/