Sitting at LaGuardia Airport, watching aircraft get deiced, I can’t help but think of USAir Flight 405, an aircraft whose fate was determined by ice contamination on the wings which developed after the aircraft was deiced.
Many of you, I’m sure remember that accident because it shined a light on FAA deicing requirements and industry practices and procedures related to deicing. The aircraft on that doomed flight was a Fokker 28-4000 that crashed on takeoff one wintery night in 1992. Of 51 souls on board, including 4 crewmembers, 27 perished that day, including the captain.
For me, the accident had a personal connection. At the time, before serving as an NTSB Member, I was the chair of the mechanic’s union flight safety committee at USAir. As chair, I headed up the team that looked at whether there were any maintenance issues involved in the causes of the accident. At the time, USAir maintenance was responsible for deicing USAir’s aircraft at LaGuardia and all its maintenance stations. Today, deicing is rarely done by mechanics, usually ramp personnel or contractors are responsible. But that doesn’t affect the point of my story.
As with any major accident, we immediately dispatched our team to LaGuardia to work with the NTSB. Since there were no more flights from Boston that night, I drove down and arrived before first light the next morning. On the long drive down, I had plenty of time to think about the role maintenance might have played. An aircraft crashing on take off in freezing weather certainly raised the possibility that something had gone wrong with the deicing. And that the mechanics were somehow responsible. While I always kept an open mind on what could cause an accident and how maintenance could have been involved, the mechanic in me was always hoping that maintenance wasn’t a factor.
But once on scene, there was no time for speculation. Our job as part of the accident investigation team was to put every aspect of maintenance that could have been a factor in the accident under a microscope. In this case, that included every aspect of deicing the F-28 before takeoff that night– from the procedures followed to the equipment and deicing fluid used to the personnel performing the work, their training, qualifications and experience.
As each of these components of the deicing process that night were scrutinized, it became apparent that the mechanics involved had followed USAir company procedures properly and that neither their actions nor the equipment and fluid used were the cause. The NTSB ultimately determined that the cause of the accident was the failure of the FAA and the airline industry to provide flight crews with procedures to follow when flights are delayed in icing conditions and the failure of the crew to positively determine that the wings were free of ice after being exposed to freezing rain 35 minutes after deicing.
Moral of the Story: Follow procedures. You don’t ever want an accident to be the result of your failure to do so.