FAA, airports, and aircraft manufacturers have worked to meet the demands of continued growth in passenger and cargo traffic in different ways. FAA has worked to improve the capacity and efficiency of the national airspace system to accommodate a greater number and variety of aircraft by, for example, improving air traffic management systems and implementing domestic reduced vertical separation minimums. FAA is also currently working on the transformation of the nation’s current air traffic control system to the next generation air transportation system—a system intended to accommodate the expected growth in air traffic. However, the full implementation of the next generation air transportation system is years away. To accommodate increased traffic, airports have expanded the number of available runways and gates to service additional aircraft and in some cases new airports have been built. However, airports cannot always accommodate increased air traffic by expanding their infrastructure for a variety of reasons, including the lack of physical space to build additional runways or terminals. Aircraft manufacturers have developed larger and more efficient aircraft to meet growing passenger and freight demand. For example, Boeing introduced the first wide-body aircraft in 1969, the 747-100, which significantly changed the aviation market and was much larger than currently operated aircraft. According to Airbus, the 747-100 had roughly two and a half times more seating capacity than the largest aircraft operating at the time. Since then, other wide- bodied aircraft have been introduced to accommodate the increasing emphasis and demand placed on international service. The Airbus A380 represents another generational change in aircraft size and seating capacity. Specifically, the A380 is much larger than other aircraft, with a wingspan of about 262 feet, a tail fin reaching almost 80 feet high, a maximum takeoff weight in excess of 1.2 million pounds, and seating between 555 and 853 passengers. In comparison, the largest commercial aircraft in use today, the Boeing 747-400, has a wingspan of 211 feet, a tail fin about 64 feet high, a maximum takeoff weight of 875,000 pounds, and can seat between 416 and 660 passengers. Although the A380 will be the first in the new category of large passenger aircraft, it will likely not be the last. In December 2006, Boeing announced that it received orders for its 747-8 passenger aircraft. The Boeing 747-8 is anticipated to have a wingspan of about 225 feet, a tail fin about 64 feet high, a maximum takeoff weight of about 970,000 pounds, and typically seats 467 passengers in a 3-class configuration. These dimensions place this aircraft in the same category as the A380. (Figure 2 shows the dimensions of the Boeing 747-400, Airbus A380, and Boeing 747-8 aircraft.) Airbus anticipates there will be a continued demand for larger aircraft that can connect busy and congested hubs in the future. According to its analysis, Airbus estimated that new large passenger and freight aircraft would make up about 10 percent of the overall fleet from 2004 to 2023. In contrast, Boeing, while conceding the demand for a small number of very large aircraft, projects a greater demand for smaller-sized aircraft, such as the Boeing 787, which can provide point-to-point service, especially in long distance markets. The air carriers that have ordered the A380 plan to operate at airports throughout the world, including certain U.S. airports. As a result, the A380 must comply with aviation standards set by individual countries from around the world. ICAO is the international body that seeks to harmonize global aviation standards so that worldwide civil aviation can benefit from a seamless air transportation network. Its members or contracting states, including the United States, are not legally bound to act in accordance with the ICAO standards and recommended practices. Rather, contracting states decide whether to transform the standards and recommended practices into national laws or regulations. In some cases, contracting states deviate from the ICAO standards and recommended practices, or do not implement them at all. Although ICAO has no enforcement powers and only establishes standards and recommended practices, air carriers that use airports that do not comply with them may be subject to increased insurance costs. The A380 falls under ICAO’s design standards for the largest aircraft (Code F), which require at least 60-meter-wide runways (about 200 feet) and 25-meter-wide taxiways (about 82 feet). In addition, ICAO has also established varying in-flight, landing, and takeoff separation standards for the different classes of aircraft. In the United States, FAA, an agency of the Department of Transportation (DOT), is responsible for regulating the safety of civil aviation and also establishes the standards and recommendations for the design and development of civil airports. FAA’s role as a regulator is to foster aviation safety by overseeing manufacturers and operators to enforce full compliance with safety requirements. To this end, FAA must certify any new aircraft design before that aircraft can be registered in the U.S. for operations by domestic airlines. This design certification is the foundation for many other FAA approvals, including operational approvals. When domestic aircraft manufacturers request approval of a new aircraft design, FAA uses the type certification process to ensure that the design complies with applicable requirements or airworthiness standards. Type validation is the type certification process that FAA uses for foreign or imported products, such as the A380, to ensure that the design complies with applicable FAA standards. The A380 was validated by FAA and issued a type certificate in December 2006. Also, in March 2007, Airbus completed a series of airline route proving and airport compatibility flights, which were designed to demonstrate the A380’s ability to operate at airports around the world. As part of these flights, the A380 visited four U.S. airports, including New York John F. Kennedy, Chicago O’Hare, Los Angeles, and Washington Dulles International Airports. FAA also establishes standards and recommendations for airport planning and design. Due to the size of the A380, it is subject to the FAA’s design standards for the largest aircraft (Airplane Design Group VI standards). To be in compliance with these design standards, airports are required to have 200-foot-wide runways, 100-foot-wide taxiways, and appropriate separation distances. Table 1 shows the wing span criteria for the airplane design groups and examples of aircraft that fall into each category. These design standards group aircraft by wingspan and set ranges for which the aircraft that fall within each group could operate without limitations. According to FAA standards, the A380 could operate at U.S. airports built to Design Group VI standards without the imposition of operating restrictions to the airport or aircraft. However, most U.S. airports that anticipate receiving A380 service are not built to Design Group VI standards. When airports do not or cannot meet the required FAA design standards to accommodate certain aircraft, airport officials can apply for Modifications to Standards through FAA. This would allow certain aircraft to be operated at airports under certain conditions as long as the airport can provide an acceptable level of safety comparable to that of an airport meeting Design Group VI standards. The use of Modifications to Standards is a process to provide U.S. airports flexibility when the required design group standards cannot be met to accommodate certain operations, as long as an acceptable level of safety can be maintained. After reviewing the design specifications of the A380, FAA issued interim guidance in 2003 that allows the A380 to operate at airports with runways and taxiways that do not fully meet Design Group VI standards. In order to avoid costly or impractical changes to upgrade runways and taxiway systems to Design Group VI and be approved for A380 operations under the interim guidance, FAA must approve an airport’s request for Modifications to Standards when the standards are not met. These modifications may include A380-specific operational restrictions or special operating procedures to ensure that existing non-standard infrastructure is providing an acceptable level of safety. The A380 will be the first of a new category of large passenger aircraft introduced into the national airspace system in the coming years. The size of the aircraft poses a number of potential safety challenges for airports. Most U.S. airports were not designed to receive aircraft the size of the A380 and therefore, the width of their runways and taxiways do not meet FAA safety standards. As a result, airports expecting A380 service need to modify their infrastructure or impose operating restrictions on the A380 and other aircraft to assure that safety is maintained. In addition, research data suggests that the wake turbulence created by the A380 is stronger than any aircraft in use today and would require greater separation from other aircraft during landing and takeoff. Although the A380 is equipped with some safety enhancements, such as new internal and exterior materials designed to reduce flammability and an external taxiing camera system to enhance pilot vision on the ground, the A380 poses safety challenges for fire and rescue officials due to its larger size, upper deck, fuel capacity, and the number of passengers. The fire and rescue officials at the airports we visited were confident in their ability to respond to an A380 incident, but almost all of them identified some equipment, personnel, or training needs that would improve their ability to respond to emergencies involving the A380. Similar concerns were raised for the Boeing 747 aircraft when it was introduced to the market, and these potential safety challenges would likely be present for other similarly-sized aircraft introduced in the future. FAA, ICAO, Airbus, and airports have taken a number of steps to mitigate potential safety challenges posed by the A380. The A380 offers air carriers and airports several safety enhancements over existing aircraft. For example, it has a cockpit with the latest advanced displays and avionics, and is equipped with an external taxiing camera system to assist flight crews in keeping the aircraft in the center of taxiways when moving on the airfield.