The September 11, 2001, terrorist attacks forced the U.S. Department of Transportation (DOT) to take the unprecedented step of closing down the nation's aviation system and, further, to restrict operations in parts of the system. The attacks also affected the public's demand for air travel by increasing concerns for air safety and decreasing the likelihood of quick recovery for an economy that was already weak.
The result was an exceptional fall in all types of flight operations recorded by the Federal Aviation Administration: 2 million (35 percent) fewer operations in September 2001 than in September 2000. The 233,000 cancellations for the 12 months ending September 2001 were 42 percent higher than the previous high set in September 2000. The 86,000 cancellations recorded between September 11 and September 30 were higher than for any year (ending in September) since 1995. Even these numbers understate the impact of the attacks, because flights that are offered for sale, but canceled more than 7 days before scheduled departure, are not reported to the Bureau of Transportation Statistics. Airlines reported 151,000 flights for September 1 to 10 but only 139,000 flights for September 21 to 30, a decline of almost 9 percent.
SOURCES: U.S. Department of Transportation, Bureau of Transportation Statistics, analysis based on U.S. Department of Transportation, Federal Aviation Administration, Operations Network (OPSNET) Database, as of May 2002.