Incident Overview
An aircraft conducting a scheduled flight from Atlanta, Georgia, experienced an accident during its approach to Chattanooga Airport. The approach was conducted in poor weather conditions with heavy rain and limited visibility. On short final, the aircraft struck approach lights located 1,600 feet short of Runway 20 threshold. After striking the lights, the aircraft impacted the ground, separated its left wing, and skidded for an additional 1,200 feet before coming to rest 250 feet to the left of the runway centerline.
Occupant Status
All 79 occupants evacuated the aircraft safely. Seven passengers sustained minor injuries.
Probable Cause
The official investigation determined that the pilot did not recognize the need to correct an excessive rate of descent after the aircraft had passed decision height. This occurred despite two verbal reports of increasing sink rate by the first officer. The captain disregarded these reports, possibly due to the influence of a visual illusion caused by the refraction of light through the heavy rain on the windshield. The excessive rate of descent was initiated by a wind shear condition extending in the lower levels of the approach path and a glide slope that tended toward the lower signal limit.