Agency Says Numerous ADs And SAFOs Increased Air Safety In Recent Years

In the wake of Thursday's crash of Continental Connection flight 3407 into a Buffalo, NY suburb, and in particular the speculation regarding the role icing may have played in the tragedy, the Federal Aviation Administration on Friday released a summary of numerous short-and long-term safety actions it has taken over the past 15 years to improve safety of aircraft that encounter icing conditions on the ground and in flight:

Background

Since 1994, the FAA has issued more than 100 airworthiness directives to address icing safety issues on more than 50 specific aircraft types. These orders cover safety issues ranging from crew operating procedures in the icing environment to direct design changes. The FAA also has changed airplane flight manuals and other operating documents to address icing safety, and issued bulletins and alerts to operators emphasizing icing safety issues.

In addition to many short-term initiatives, the FAA has issued one final rule, has another in final executive coordination, and two proposed rules under development that address NTSB recommendations.

FAA Actions

The following FAA actions have reduced icing-related accidents:

• In 1996, the FAA mandated (AD 96-09-25) an Airplane Flight Manual (AFM) revision to limit or prohibit the use of various flight control devices and provide flight crews with recognition queues and procedures for exiting from severe icing conditions.
• In 1999, the FAA issued an Airworthiness Directive (AD 99-19-18) that mandated revisions to AFM to advise flight crews to activate airframe pneumatic de-icing boots at the first sign of ice accumulation.
• The FAA has issued ADs on aircraft such as the Mitsubishi MU-2 and the Cessna 208, given their history of icing-related accidents and incidents.
• On March 29, 2006, the FAA issued Safety Alert for Operators (SAFO 06002) on ground deicing practices for turbine airplanes in nonscheduled Part 135 and Part 91 service.
• On October 6, 2006, the FAA issued a Safety Alert for Operators (SAFO 06014) to warn against the hazards posed by polished frost.
• On November 11, 2006, the FAA issued a Safety Alert for Operators (SAFO 06016) to increase awareness of in-flight icing dangers for pilots flying turbo-propeller powered airplanes.
• On November 30, 2007, the FAA issued Safety Alert for Operators (SAFO 07009) to inform owners, operators, and FAA entities of training requirements for pilots of CE-208 (Cessna Caravan 1) and CE-208B (Cessna Grand Caravan) airplanes for flight into icing conditions.
• In December 2007, the FAA issued Advisory Circular (AC 91-74A) on the affect of ice crystals on turbine engines.
• On May 8, 2008, the FAA proposed a rule to remove language from its regulations that allowed some operators - not commercial airplanes - to operate with polished frost. Unlike commercial airplanes which must have a clean wing, corporate aircraft were permitted to fly with smooth or "polished frost." That practice has been deemed unsafe. The comment period closed August 6, 2008.
• On May 20, 2008, the FAA issued Safety Alert for Operators (SAFO 0812) on aircraft taxi operations during snow and ice conditions.
• On February 11, 2009, the FAA issued Safety Alert for Operators (SAFO 09004) to emphasize preflight and in-flight planning for winter airport operations for taxi, takeoff, and landing. It also elaborates on SAFO 0812.

Proposed New Rule Mandates Icing Detection

On April 26, 2007, the FAA proposed a rule to require an effective way to detect ice buildup or let pilots know that icing conditions exist, and produce timely activation of the ice-protection system. It would help avoid accidents and incidents where pilots are either completely unaware of ice accumulation or think the icing is not significant enough to warrant turning on their ice-protection equipment. This rule would mandate that future airplane designs use one of three methods to detect icing and activate the ice-protection system:

1. An ice-detection system that automatically activates or alerts pilots to activate the ice-protection system
2. A definition of visual signs of ice buildup on a specified surface (e.g., windshield wiper post or wings) combined with an advisory system that alerts the pilots to activate the ice-protection system
3. Identification of temperature and moisture conditions conducive to airframe icing that would be used as a cue by pilots to activate the ice-protection system.

The rule would further require that after initial activation of the ice-protection system, the system must operate continuously, automatically turn on and off, or there must be an alert to tell pilots when the system is to be cycled. The comment period closed July 25, 2007. The rule is currently in the final stages of executive review.

Final Rule Introduces New Airworthiness Standards

On August 8, 2007, an FAA final rule introduced new airworthiness standards for the performance and handling characteristics of transport airplanes in icing conditions. The new rule improves the level of safety for new airplane designs when operating in icing conditions, and will harmonize the U.S. and European airworthiness standards for flight in icing conditions.

The rule adds a comprehensive set of airworthiness requirements that manufacturers must meet to receive approval for flight in icing conditions, including specific performance and handling qualities requirements, and the ice accretion (size, shape, location, and texture of ice) that must be considered for each phase of flight. These revisions will ensure that minimum operating speeds determined during the certification of all future transport airplanes will provide adequate maneuvering capability in icing conditions for all phases of flight.

Rules Under Development

The FAA is developing a proposed rule change under which air carrier airplanes are operated that would require either the installation of ice detection equipment or changes to the procedures for activating the ice-protection system to ensure timely activation of the ice-protection system.  This proposed rule would apply to all current and future airplanes in service with air carriers whose maximum takeoff weight is less than 60,000 pounds.

The FAA is also developing a proposed rule to address supercooled large drop icing, which is outside the icing envelope considered by the current icing certification requirements.  The proposed rule would improve safety by taking into account supercooled large-drop icing conditions for transport category airplanes most affected by these icing conditions, mixed-phase and ice-crystal conditions for all transport category airplanes, and supercooled large drop, mixed phase, and ice-crystal icing conditions for all turbine engines. An economic analysis is currently being prepared.

FMI: www.faa.gov/other_visit/aviation_industry/airline_operators/airline_safety/safo/all_safos/