According to NTSB’s aviation accident database, from 1998 to 2009 one large commercial airplane was involved in a nonfatal accident after encountering icing conditions during flight and five large commercial airplanes were involved in nonfatal accidents related to snow or ice on runways. Although there have been few accidents, FAA and others recognize that incidents are potential precursors to accidents. Data on hundreds of incidents that occurred during this period reveal that icing and contaminated runways pose substantial risk to aviation safety. FAA’s database of incidents includes 200 icing-related incidents involving large commercial airplanes that occurred from 1998 through 2007. These data covered a broad set of events, such as the collision of two airplanes at an ice-covered gate, and an airplane that hit the right main gear against the runway and scraped the left wing down the runway for about 63 feet while attempting to land with ice accumulation on the aircraft. During this same time period, NASA’s Aviation Safety Reporting System (ASRS) received over 600 icing and winter weather-related incident involving large commercial airplanes. These incidents reveal a variety of safety issues such as runways contaminated by snow or ice, ground deicing problems, and in-flight icing encounters. This suggests that risks from icing and other winter weather operating conditions may be greater than indicated by NTSB’s accident database and by FAA’s incident database. FAA officials point out that there is no defined reporting threshold for ASRS reports and because they are developed from personal narrative, they can be subjective. However, these officials agree that the ASRS events must be thoroughly reviewed and evaluated for content to determine the relevancy to icing and the extent and severity of the safety issue. The contents of the ASRS data system also demonstrate the importance of aggregating data from all available sources to understand a safety concern. See table 1 for the number of icing and winter weather-related incident reports from ASRS for large commercial airplanes. While this testimony focuses on large commercial airplanes, I would like to note that from 1998 to 2007, small commercial airplanes and noncommercial airplanes experienced more icing-related accidents and fatalities than did large commercial airplanes, as shown in table 2. This is largely because, compared to large commercial airplanes, small commercial airplanes and noncommercial airplanes (1) operate at lower altitudes that have more frequent icing conditions, (2) have a higher icing collection efficiency due to their smaller scale, (3) are more greatly impacted by ice as a result of their smaller scale, (4) tend to have deicing equipment rather than fully evaporative anti-icing equipment, (5) may not have ice protection systems that are certified, nor are they required to be, because the airplane is not approved for flight in known icing conditions, and (6) may not have ice protections systems installed. Following the 1994 fatal crash of American Eagle Flight 4184 in Roselawn, Indiana, FAA issued a multiyear plan in 1997for improving the safety of aircraft operating in icing conditions and created a steering committee to monitor the progress of the planned activities. Over the last decade, FAA made progress on the implementation of the objectives specified in its multiyear plan by issuing or amending regulations, airworthiness directives (ADs), and voluntary guidance to provide icing-related safety oversight. For example, FAA issued three final rules on icing: in August 2007, a rule introduced new airworthiness standards to establish comprehensive requirements for the performance and handling characteristics of transport category airplanes in icing conditions; in August 2009, a rule required a means to ensure timely activation of the ice protection system on transport category airplanes; and in December 2009, a rule required pilots to ensure that the wings of their aircraft are free of polished frost. FAA has also proposed an icing-related rule in November 2009, on which the public comment period closed February 22, 2010; this rule would require the timely activation of ice protection equipment on commercial aircraft during icing conditions and weather conditions conducive to ice formation on the aircraft. In addition, FAA is developing a proposed rule to amend its standards for transport category airplanes to address supercooled large drop icing, which is outside the range of icing conditions covered by the current standards. Since 1997, FAA has issued over 100 ADs to address icing safety issues involving more than 50 specific types of aircraft, including ADs that required the installation of new software on certain aircraft and another that required operators and manufactures to install placards displaying procedures for use of an anti- icing switch on certain aircraft. Additionally, FAA has issued bulletins and alerts to operators emphasizing icing safety issues. As part of our ongoing review, we will conduct a more comprehensive evaluation of FAA’s progress on the implementation of the objectives specified in its multiyear in-flight icing plan. Among other things, we will also analyze the results of FAA’s surveillance activities related to monitoring air carriers’ compliance with existing regulations and ADs. FAA also provided funding for a variety of icing-related purposes. For example, FAA has supported NASA research related to severe icing conditions and the National Center for Atmospheric Research (NCAR) research related to weather and aircraft icing. Furthermore, FAA has provided almost $200 million to airports through the Airport Improvement Program (AIP) to construct deicing facilities and to acquire aircraft deicing equipment from 1999 to 2009. See appendix I for a detailed listing of AIP icing-related funding by state, city, and year. Runway safety is a key concern for aviation safety and especially critical during winter weather operations. For example, in December 2005, a passenger jet landed on a snowy runway at Chicago’s Midway Airport, rolled through an airport perimeter fence onto an adjacent roadway, and struck an automobile, killing a child and injuring 4 other occupants of the automobile and 18 airline passengers. According to the Flight Safety Foundation, from 1995 through 2008, 30 percent of global aviation accidents were runway-related and “ineffective braking/runway contamination” is the fourth largest causal factor in runway excursions that occur during landing. In fiscal year 2000, FAA’s Office of Airport Safety and Standards initiated a program, which includes making funds available to airports through AIP, to accelerate improvements in runway safety areas at commercial service airports that did not meet FAA design standards. EMAS uses materials of closely controlled strength and density placed at the end of the runway to stop or greatly slow an aircraft that overruns the runway. According to FAA, the best material found to date is a lightweight crushable concrete. 2010. To date there have been five successful EMAS captures of overrunning aircraft. Government and industry stakeholders, external to FAA, also contribute to the effort to increase aviation safety in winter weather/icing conditions. For example, NTSB investigates and reports on civil aviation accidents and issues safety recommendations to FAA and others, some of which it deems most critical and places on a list of “Most Wanted” recommendations. Since 1996, NTSB has issued 82 recommendations to FAA aimed at reducing risks from in-flight structural icing, engine and aircraft component icing, runway condition and contamination, ground icing, and winter weather operations. NTSB’s icing-related recommendations to FAA have called for FAA to, among other things, strengthen its requirements for certifying aircraft for flying in icing conditions, sponsor the development of weather forecasts that define locations with icing conditions, and enhance its training requirements for pilots. NTSB has closed 39 of these recommendations (48 percent) as having been implemented by FAA, and has classified another 25 (30 percent) as FAA having made acceptable progress. This combined 78 percent acceptance rate is similar to the rate for all of NTSB’s aviation recommendations. For more than 30 years, NASA has conducted and sponsored fundamental and applied research related to icing. The research addresses icing causes, effects, and mitigations. For instance, NASA has conducted extensive research to characterize and simulate supercooled large drop icing conditions to inform a pending FAA rule related to the topic. NASA participated in research activities, partially funded by FAA, that developed additional knowledge and strategies which allowed forecasters to more precisely locate supercooled large drop icing conditions. Furthermore, NASA has an icing program, focused generally on research related to the effects of in-flight icing on airframes and engines for many types of flight vehicles. NASA has developed icing simulation capabilities that allow researchers, manufacturers, and certification authorities to better understand the growth and effects of ice on aircraft surfaces. NASA also produced a set of training materials for pilots operating in winter weather conditions. In recent years, NASA’s funding decreased significantly, limiting the capability of its icing research program. NOAA, the National Weather Service (NWS), and NCAR have efforts directed and funded by FAA related to predicting the location and severity of icing occurrences. NWS operates icing prediction systems and NCAR conducts research to determine more efficient methods to complete this task. For example, in 2006, NCAR introduced a new Web-based icing forecast tool that allows meteorologists and airline dispatchers to warn pilots about icing hazards up to 12 hours in advance. NCAR developed this tool using FAA funding and NWS facilitates the operation of the new icing forecasting tool. NWS also posts on the agency’s Web site maps of current icing conditions, pilot reports, forecasts, and freezing level graphics. The private sector has also contributed to efforts to prevent accidents and incidents related to icing and winter weather conditions. For example, as shown in figure 2, aircraft manufacturers have deployed various technologies such as wing deicers, anti-icing systems, and heated wings. In addition, airports operate ground deicing and runway clearing programs that help ensure clean wings (see fig. 3) and runways.