Timeline of NTSB Icing Recommendations


October 31, 1994:Crash of ATR 72-212 (turboprop) at Roselawn, ID. 68 people were killed. American subsequently moved operations of ATR 72 to the Caribbean and southern U.S.

July 9, 1996: NTSB Aircraft Accident Report regarding Roselawn accident released. Probable cause was a “loss of control, attributed to a sudden and unexpected aileron hinge moment reversal that occurred after a ridge of ice accreted beyond the deice boots.”

August 8, 1996: NTSB Issues Safety Recommendations A-96-48 through A-96-69. Among these are Recommendations A-96-54 and A-96-56 which read as follows:

  • Revise the icing criteria published in 14 Code of Federal Regulations (CFR), Parts 23 and 25, in light of both recent research into aircraft ice accretion under varying conditions of liquid water content, drop size distribution, and temperature, and recent developments in both the design and use of aircraft. Also, expand the Appendix C icing certification envelope to include freezing drizzle/freezing rain and mixed water/ice crystal conditions, as necessary. (A-96-54

 

  • Revise the icing certification testing regulation to ensure that airplanes are properly tested for all conditions in which they are authorized to operate, or are otherwise shown to be capable of safe flight into such conditions. If safe operations cannot be demonstrated by the manufacturer, operational limitations should be imposed to prohibit flight in such conditions and flightcrews should be provided with the means to positively determine when they are in icing conditions that exceed the limits for aircraft certification. (A-96-56)

 

August 20, 1997: NTSB classifies the FAA’s response to A-96-54 and A-96-56 as “Open-Acceptable” after FAA created an Aviation Rulemaking Advisory Committee (ARAC) to develop certification criteria for the safe operation of aircraft in icing conditions.

1999: De Havilland Dash 8 Series Q402 receives type certification.

January 27, 2003: NTSB writes letter to FAA regarding the work of the ARAC, saying it is concerned about the “slow pace of the [the ARAC’s work].” The NTSB stated, “Although the FAA, through its referral of this work to the ARAC, is responding to these recommendations, the Safety Board remains concerned that in the 6 years since these recommendations were issued, the work has not been completed. The Board would like the FAA to provide a schedule for completion of the recommended actions.”

May 19, 2003: FAA responds to NTSB’s concern, stating that “The FAA will publish a notice of proposed rulemaking based on these recommendations by June 2004.”

November 9, 2004: After an NTSB meeting regarding “Most Wanted Recommendations,” NTSB classifies Recommendations A-96-54 and A-96-56 as “Open-Unacceptable.”

February 15, 2005: Cessna Citation 560, owned by Circuit City Stores, Inc. crashed in Pueblo, CO 4 miles east of Pueblo Memorial Airport. 8 people were killed. NTSB stated probable causes as: “the flight crew’s failure to effectively monitor and maintain airspeed and comply with procedures for deice boot activation on the approach, which caused an aerodynamic stall from which they did not recover. Contributing to the accident was the Federal Aviation Administration’s failure to establish adequate certification requirements for flight into icing conditions, which led to the inadequate stall warning margin provided by the airplane’s stall warning system.” (Emphasis added)

May 10, 2006: Two years after the FAA’s own deadline for action, the NTSB issued a statement again lamenting the lack of action: “There does not appear to have been any progress since the FAA previously informed the Board of the status of this recommendation on September 15, 2003.”

February 27, 2007: From NTSB update on FAA action regarding the Recommendations: “[T]he FAA has still not received the recommendations from [its working group studying deicing certification], prepared regulatory analyses, issued the NPRM, analyzed comments, or completed the many other tasks involved in issuing new regulations.”

April 16, 2008: Aircraft involved in Buffalo crash issued certificate of airworthiness.

February 12, 2009: Crash of de Havilland Dash 8 Q-402 (turboprop) outside of Buffalo, NY killed 50 people. Cockpit Voice Recorder indicated that crew mentioned significant ice buildup on windshield and leading edge of wings.