Aircraft Accidents and Lessons Unlearned I: Air Midwest 5481
The purpose of National Transportation Safety Board (NTSB) accident investigations are a chance for understanding; if they concentrate solely on closure and not on lessons learned, then the transportation disaster only becomes more tragic; the aviation industry gains no knowledge to prevent a similar accident from taking place; the tragic events will re-occur.
The ‘product’ of the NTSB is its reports, results of painstaking investigating into an accident. The most important parts of the accident report are the Probable Cause and the Recommendations. Trivializing the Probable Cause and/or the Recommendations out of a rush to meet a deadline is wrong. Trivializing because one doesn’t understand the facts is unforgiveable.
To make my point, let’s use an imaginary airline: Brand X; and an imaginary aircraft: ABC Aircraft’s Zeta-1. If a Brand X Airline’s Zeta-1 crashes, the NTSB accident report must outline why that Zeta-1 crashed. If the accident was attributed to something that goes beyond Brand X and the Zeta-1, e.g. approved procedures were not followed, then the airline industry itself faces a safety crisis; the accident report must prevent any further Zeta-1 crashes for all airlines and operators, not just Brand X; it must also prevent accidents that stem from people not following approved procedures. To do this, the NTSB must understand the airline industry and what contributing factors, whether due to weather, pilot training, manufacturer design or maintenance, led to the accident. Otherwise the accident report is useless.
Aside from the tragic loss of life, the Air Midwest (AMW) 5481 accident’s findings proved that the most important contributors to the accident were lost in all the ‘expert’ talk. The NTSB focused the investigation on the obvious problems, while ignoring the fundamental issues at the core that dealt with management at both the Repair Station and the airline.
The air carrier, AMW, contracted with Part 145 repair station, Raytheon Aerospace (RA) to perform maintenance on AMW’s fleet of Beech 1900Ds; both companies made many mistakes at the management level, e.g. tracking mechanic training, violating the Federal Aviation Regulations (FAR) and being selective with maintenance manual references. What followed was an amateurish shell game – albeit, well-played – where management for AMW and RA diverted attention away from many important safety concerns.
From the first hours after the accident on January 8, 2003, to the NTSB Hearing in May 2003, the Maintenance Investigatory team (MIT) was misdirected by the airline from who was responsible and for what, e.g. who the mechanics worked for and who contracted maintenance services to who. The Huntington, West Virginia hangar’s decision to ignore the FARs and their approved procedures crippled their effectiveness. When an accident would occur was only a matter of time.
Why RA’s and AMW’s misleading succeeded was due to the NTSB management’s unfamiliarity with the commercial aviation industry, in this case: the airline system. For decades the NTSB employed a staff made up mostly of engineers; qualified engineers in their own wheelhouse, but ignorant of an airline’s maintenance organization culture. These staff specialists eventually migrate into the NTSB’s management, making investigatory decisions without a clear understanding of how the airline industry works. And that is the NTSB’s Achilles’ heel; they lack a basic understanding of the industry they investigate.
The Air Midwest accident report succeeded in determining what ‘caused the’ accident; however the report failed to discover ‘the cause’ of the accident. Air Midwest 5481 crashed due to several problems, both specific and systemic, e.g. limited elevator authority due to an improper rigging of the elevators was specific to that aircraft; the accident may not have happened if another aircraft replaced it on the line that day.
But ‘the cause(s)’ of the Air Midwest 5481 accident – major contributors to this disaster – are systemic, e.g. the aircraft being out of center of gravity limits. This issue may not have been discovered if that particular aircraft hadn’t been used on that particular flight that particular day; the problem was probably occurring on multiple aircraft on that ramp. This individual aircraft whose problems extended to unsafe maintenance practices was key to discovering that loading aircraft out of center of gravity may have been more frequent than realized up until then.
What is also systemic? The circumstances that led to the unsafe maintenance practices; the elevators being rigged incorrectly to begin with; this is even more crucial than the center of gravity problem because how it became incorrectly rigged was mostly ignored by the report. The NTSB, in pursuing what ‘caused the’ Air Midwest 5481 accident, ignored ‘the cause’ of the accident; a cause that could have resulted in similar problems occurring at another airline … and did. The AMW accident was a result of maintenance-culture intensive problems.
This is most evident in the writing of the Probable Cause(s) and the Recommendations. The Findings mention the problems experienced by AMW’s and RA’s confused relationship and control of the maintenance workforce, but the accident report trivializes the importance of the problems. In its Recommendations, the NTSB managed to reword FARs that had been written years before, yet were ignored by the airline, e.g. FAR 121.369: Manual Requirements, or 121.371: Required Inspection Personnel. Reminding the industry about decades-old regulations do nothing to improve safety; instead, it shows a complete lack of understanding of what is necessary to ‘fix the problem’, or in this case … problems.
AMW and RA conducted heavy maintenance in five different hangars of which Huntington, WV, was one. Each hangar followed the same procedures, each with the same systemic problems: opportunities to stray from the procedures and FARs that led to the Air Midwest 5481 accident. Air Midwest flew forty-three Beech 1900D aircraft; they routed their fleet through these five hangars for everything from daily checks to heavy Detail inspections/maintenance.
When the MIT discovered that the accident aircraft’s elevators were rigged incorrectly at Huntington, that AMW and RA did not follow the approved procedures and FARs, then any rigging procedures performed in any of the five hangars over the contract’s history were suspected to be unsafe and out of limits. Riggings included in the installations and operational checks of engines, doors, landing gear and flight controls, e.g. ailerons, flaps, elevators, and rudders, on all forty-three aircraft. These should have been checked fleet-wide.
Instead, the NTSB reworded the FARs. The push to put out a report ignored the fundamental point of the accident investigation: If one airline could neglect the FARs and their approved procedures, then another airline could do the same thing elsewhere.
Important lessons were not learned; the tragic circumstances re-occurred; similar problems existed elsewhere. And on August 26, 2003, 231 days later, another Beech 1900D crashed, under similar conditions, in the north Atlantic. Why? Because the approved procedures were not followed.