Page:CAB Accident Report, American Airlines Flight 383.pdf/27

– 26 – of the total weather picture known to the pilots and despite the fact that VFR conditions existed at the airport, it is believed that a more prudent judgment would have been either for the flight to have conducted an instrument approach, or to have delayed the approach until the storm had moved beyond the airport.

It is further concluded that after the flight turned onto the base leg inflight visibility was sharply reduced and that both pilots became preoccupied in maintaining visual contact with the runway, resulting in inattention to, and improper monitoring of, the altitude reference instruments.

The last point at which this accident could have been averted was approximately 13 seconds prior to impact. At this time the aircraft was descending below the level of the airport and any visual contact with the field or approach lights would have been lost immediately. The flight then should have, and could have accomplished a pull-up and go-around within the operating capabilities of the aircraft. However, at that point, as previously stated in the analysis, the accumulation of many factors either delayed or precluded proper recognition of the situation.

Regardless of the possible mitigating circumstances there can be no valid excuse for such a gross deviation from safe operating altitude as was presented in this accident. The approach procedures outlined in the carrier's manuals, the number of cockpit altitude reference instruments and related monitoring procedures, the approach aids available, and the skills expected of airline pilot, are all protective devices design to prevent the development of such a situation. However, it is apparent that these devices were not fully utilized in the conduct of this approach.

While the circumstances and conditions of the accident are greatly different from those involved in another Boeing 727 accident which occurred at Salt Lake City, Utah, and for which the Board has already issued a report, there are some elements in common relative to pilot/crew judgment. For this reason the Board must re-emphasize that the responsibility and authority committed to an airline captain requires the exercise of sound judgment and strict adherence to prescribed practices and procedures. Any deviation can only result in a compromise of aviation safety. Airline management, too, has a heavy responsibility for devising, developing, and implementing methods and procedures designed to insure that all of their pilot personnel constantly exercise a conservative, prudent, approach to their daily work.

Probable Cause

The Board determines that the probable cause of this accident was the failure of the crew to properly monitor the altimeters during a visual approach into deteriorating visibility conditions.

3. RECOMMENDATIONS

The Board is aware of industry studies now under consideration pertaining to altitude reference instrumentation and cockpit instrument display. Included in these programs is the development of aural and visual low altitude warning features that can be incorporated into the aircraft altimetry system. Although no deficiencies have been found in the instrumentation presently employed in commercial