Jim Hall: Aircraft icing needs harder look
Thursday’s crash of a de Havilland Dash 8 Q400 in Clarence was deeply saddening. Fifty persons were killed in the tragedy, and the 2z-year period of fatality- free flying in commercial aviation was brought abruptly to an end.More tragic, this crash was foreseeable and likely preventable, if not for the preference of profit over safety in some of the aviation industry and for the lax oversight of the Federal Aviation Administration in its failure to adequately address known safety risks related to icing.
Initial reports strongly indicate that airframe icing played a major role in the crash of this turboprop aircraft. This type of occurrence is not without precedent. On Oct. 31, 1994, American Eagle Flight 4184 dropped from the sky when ice accumulated on its wings. It crashed into a soybean field in Roselawn, Ind., killing all 68 people onboard. On Jan. 9, 1997, Comair flight 3272 dropped from the sky over Monroe, Mich. when ice accumulated on its wings, killing all 29 people on board.
Like Thursday’s crash, both of these planes were turboprop-an Avions de Transport Regional 72 and an Embraer 120, respectively. Both aircraft were equipped with pneumatic deicing boots, a technology invented in the 1930s that has not changed much since.
As chairman of the National Transportation Safety Board, I oversaw the investigation into the Roselawn and Monroe crashes. It became apparent that, while deicing boots are more fuel efficient than the heated wing technology that larger jets use, they are not as effective at reducing the risk of an icing accident.
Furthermore, the FAA is charged with overseeing the certification process of each make and model of aircraft, yet we found in our investigation that the FAA failed to ensure that this certification adequately accounted for hazards that can result from all known icing conditions. After our extensive investigation at Roselawn concluded, I signed the NTSB’s recommendations to the FAA regarding these issues.
More than 10 years later, the FAA has not adequately addressed these concerns, and the NTSB has placed safe flight in icing conditions on its “Most Wanted” safety improvements list.
The aircraft model that crashed Thursday was certified by the FAA on Jan. 26, 2000, and the accident aircraft itself was not manufactured until 2008-well after the Roselawn recommendations were issued and with full knowledge of the dangers that turboprops and deicing boots face in freezing conditions.
There was no move to incorporate the more effective (but more expensive) heated wing technology. What’s more, an airworthiness directive published by the FAA in 1996 notes that the earlier, 40-seat model of DHC-8 aircraft had an unsafe condition which could result in loss of control of the aircraft when flaps were extended during icing conditions-as they were in Thursday’s crash-and further that the autopilot should not be engaged in “severe icing conditions,” a vaguely defined term.
But because the FAA basically ignored the NTSB’s recommendation to adequately test aircraft in these conditions before declaring them airworthy, the certification of this new version of the DHC-8 went along without a hitch. The most substantial change to the new model was not related to safety: the aircraft was stretched to allow 78 passengers to be carried by the aircraft. In short, even in light of the Roselawn and Monroe accidents, safety was compromised so that these aircraft would be allowed to fly more people at cheaper cost.
In this instance, the FAA and the airline industry clearly placed a higher value on profit than on their passengers’ safety. Well-known risks were overlooked, well-documented recommendations were ignored. That this plane was allowed to fly in dangerous conditions for which it was not thoroughly tested and prepared, and without recommended safety measures and devices in place, demonstrates this.
This attitude must change. The NTSB should move quickly to identify any deficiencies and FAA should take the requested action, such as prohibiting this aircraft from operating in icing conditions until remedies are established. I hope this accident will finally cause the FAA and the commercial aviation industry to take icing risks seriously so that a tragedy such as this will not happen again.
Jim Hall, an attorney with Nolan Law Group, was chairman of the National Transportation Safety Board from 1994 to 2001.