- United DC-10 at Sioux City
- Accident Overview
- Accident Board Findings
- Accident Board Recommendations
- Relevant Regulations / Policy / Background
- Prevailing Cultural / Organizational Factors
- Key Safety Issue(s)
- Safety Assumptions
- Resulting Safety Initiatives
- Airworthiness Directives (ADs) Issued
- Common Themes
- Related Accidents / Incidents
- Lessons Learned
- United DC-10 at Sioux City
Accident Board Recommendations
The NTSB issued a total of 29 safety recommendations for this accident investigation. Twenty-three of the recommendations were issued to the FAA, one was issued to the Air Transport Association, one was issued to the Aerospace Industries Association of America, Inc., and four were issued to the U.S. Air Force.
The following is a brief summary of the safety recommendations, which have been organized under seven categories:
- Nondestructive inspection of critical rotating parts: twelve of the safety recommendations related to inspections of critical rotating parts, both general and specific to this part failure, were issued. These recommendations included improving inspection processes by incorporating areas of emerging technologies that may improve reliability, requiring operators and industry to incorporate improved and redundant inspection processes for rotating parts and mandating GE service bulletin inspections of the CF6 fan disks.
- Aircraft control systems: two safety recommendations that addressed aircraft control systems were issued. The first recommendation encouraged additional research and development for backup control systems for new wide body aircraft, and the second was to conduct a safety review relative to the redundancy and protection of power sources for flight and engine control of currently certified aircraft as a result of lessons learned from the Sioux City accident.
- Engine uncontained failures: two safety recommendations that addressed engine uncontained failure were issued. The first recommendation was to analyze the dispersion pattern, fragment size, and energy level of uncontained debris and update AC 20-128 for future aircraft certification. The second was to create a historic database of engine rotary failures that would benefit design assessments and safety analysis.
- Record keeping: one safety recommendation was issued for record keeping. It recommended that the FAA conduct a comprehensive evaluation of aircraft and engine manufacturer record keeping and internal audit procedures.
- Cabin procedures: one safety recommendation was issued for cabin procedure. It addressed the importance of time management in preparation of the cabin for an impending emergency landing.
- Cabin restraint of passengers: two recommendations addressed cabin restraint of passengers. The first recommendation addressed requirements for infants and small children to be properly restrained during takeoff, landing, and turbulent conditions. The second recommendation addressed research to determine the adequacy of seatbelts to restrain children too large for safety seats and develop a suitable means of restraining such children.
- Airport procedures and equipment: nine safety recommendations were issued on airport procedures and equipment. These recommendations addressed fire fighting vehicles and rescue/fire fighting activities at accidents in crop environments on airport property.
The complete text of the recommendations is available at the following link: NTSB Recommendations