On August 21, 1995, about 1253 eastern daylight time, anEmpresa Brasileira de Aeronautica S. A. (Embraer) EMB-120RT, N256AS, airplane operated by Atlantic Southeast Airlines Inc., (ASA) as ASE flight 529, experienced the loss of a propeller blade from the left engine propeller while climbing through 18,100 feet. The airplane then crashed during an emergency landing near Carrollton, Georgia, about 31 minutes after departing the Atlanta Hartsfield International Airport, Atlanta, Georgia. The flight was a scheduled passenger flight from Atlanta to Gulfport, Mississippi, carrying 26 passengers and a crew of 3, operating according to instrument flight rules, under the provisions of Title 14 Code of Federal Regulations Part 135. The flightcrew declared an emergency and initially attempted to return to Atlanta. The flightcrew then advised that they were unable to maintain altitude and were vectored by air traffic control toward the West Georgia Regional Airport, Carrollton, Georgia, for an emergency landing. The airplane continued its descent and was destroyed by ground impact forces and postcrash fire. The captain and four passengers sustained fatal injuries. Three other passengers died of injuries in the following 30 days. The first officer, the flight attendant, and 11 passengers sustained serious injuries, and the remaining 8 passengers sustained minor injuries.
Safety issues focused on manufacturer engineering practices, propeller blade maintenance repair, propeller testing and inspection procedures, the relaying of emergency information by air traffic controllers, crew resource management training, and the design of crash axes carried in aircraft. Recommendations concerning these issues were made to the Federal Aviation Administration.
We determines that the probable cause of this accident was the in-flight fatigue fracture and separation of a propeller blade resulting in distortion of the left engine nacelle, causing excessive drag, loss of wing lift, and reduced directional control of the airplane. The fracture was caused by a fatigue crack from multiple corrosion pits that were not discovered by Hamilton Standard because of inadequate and ineffective corporate inspection and repair techniques, training, documentation, and communications.
Contributing to the accident was Hamilton Standard’s and the Federal Aviation Administration’s failure to require recurrent on-wing ultrasonic inspections for the affected propellers.
Contributing to the severity of the accident was the overcast cloud ceiling at the accident site.
As a result of the investigation, we issued recommendations to the Federal Aviation Administration.
