The Dangers of Airframe Icing

Slack & Davis aviation attorneys have specific expertise in investigating and successfully resolving cases in which airframe icing was a significant factor in the crash. The issues related to airframe icing are complex and typically involve questions about piloting procedures, aircraft characteristics, weather and pilot training. Some aircraft, such as the Cessna Caravan, have proven to be more susceptible to airframe icing than other aircraft and are susceptible to sudden loss of control in benign icing conditions.

What is Airframe Icing?
Airframe icing occurs when water droplets freeze on the external surfaces of an aircraft. In general, airframe icing is a potential flight hazard since it adds unintended weight and can significantly disrupt and destroy the functions of the aerodynamic surfaces and degrade performance of the aircraft’s propulsion system. Airframe icing alters the airplane geometry and destroys the intended aerodynamic functions of the wings, tail, ailerons, rudder, elevators and flaps. Airframe icing also affects propellers and significantly reduces engine power by blocking or clogging engine inlets.

Airframe icing can occur while the aircraft is on the ground and frost forms on the airframe. This type of icing contamination can usually be removed on larger aircraft by spraying the aircraft, before take-off, with a de-icing chemical. Frost is removed from smaller aircraft by mechanically cleaning the affected areas.

In-flight airframe icing is more problematic. When icing occurs in flight the pilot must first recognize the potential hazard and react in a timely and appropriate fashion. Even though the aircraft may be certified to fly in icing conditions and is equipped with a de-icing or anti-icing system, the aircraft’s de-icing or anti-icing systems must be able to prevent or remove sufficient ice such that the functions of the aerodynamic surfaces and the engine are preserved and protected.

Aircraft Certification Issues
Many aircraft are certified to fly in icing conditions. Despite the certification, the aircraft’s actual capability to perform in the icing environment can present serious safety issues. The Cessna Caravan is an example of an aircraft which is very susceptible to loss of control in icing conditions, but which is nonetheless certified for flight in icing conditions. A similar situation was noted in the 1994 crash of American Eagle Flight 4184 near Roselawn, Indiana.

Cessna Caravan 208B
The Cessna 208B Caravan equipped with pneumatic de-icing boots is very susceptible to airframe icing, especially in-flight airframe icing. The Caravan is certified to fly in icing conditions; however documents and testimony obtained by Slack & Davis aviation attorneys in connection with the November 2002 crash of aircraft N514DB near Parks, Arizona, contain substantial evidence that the icing certification of the 208B model was inadequate and does not meet minimum certification standards. Both the National Transportation Safety Board (NTSB), in late 2005, and the Canadian Transportation Safety Board, in early 2006, issued safety recommendations and expressed concerns about the safety of the Caravan flying under icing conditions. But the Federal Aviation Administration (FAA), which has known about the Caravan problem for years, has not taken appropriate action. The NTSB has characterized the FAA’s action, or inaction, on the NTSB’s list of icing safety issues as “unacceptable.”

American Eagle Flight 4184 (Roselawn, Indiana)
On October 31, 1994, American Eagle Flight 4184 crashed near Roselawn, Indiana. The resulting litigation, in which Slack & Davis participated, developed strong evidence that, as designed and certified, the ATR aircraft was susceptible to a loss of control in icing conditions. The control problems faced by the pilots included an aerodynamic phenomena called “control reversal” in which certain aerodynamic characteristics of the aircraft in icing were opposite to what the pilots expected. There was also evidence developed that pointed to a delay in the pilots’ recognition of and failure to appreciate the severity of the icing.

Slack & Davis aviation lawyers represent passengers and families involved in icing-related air crashes. We invite you to review our icing-related cases and contact us to learn more.

Print This Page

Cases We’ve Handled

Slack & Davis, L.L.P. (Principal office in Austin, Texas) All rights reserved. | Disclaimer | Site Map
Austin: 2705 Bee Cave Rd., Ste. 220, Austin, TX 78746 | 512.795.8686 | 800.455.8686 | Dallas: 2911 Turtle Creek Blvd., Ste. 1400, Dallas, TX 75219 | 214.528.8686
Legal website design by Creative Suitcase