WASHINGTON — American aviation officials were warned as early as 1998 that al-Qaida could "seek to hijack a commercial jet and slam it into a U.S. landmark," according to previously secret portions of a report prepared last year by the Sept. 11 commission. The officials also realized months before the Sept. 11 attacks that two of the three airports ultimately used in the hijackings had suffered repeated security lapses.
Federal Aviation Administration officials were also warned in 2001 in a report prepared for the agency that airport screeners' ability to detect possible weapons had "declined significantly" in recent years, but little was done to remedy the problem, the Sept. 11 commission found.
The White House and many members of the commission, which has completed its official work, have been battling for more than a year over the release of the commission's report on aviation failures, which was completed in August 2004.
A heavily redacted version was released by the Bush administration in January, but commission members complained that the deleted material contained information critical to the public's under standing of what went wrong on Sept. 11. In response, the administration prepared a new public version of the report, which was posted on Tuesday on the National Archives Web site.
While the new version still blacks out numerous references to particular shortcomings in aviation security, it restores several dozen other portions of the report that the administration had previously considered too secret for public release.
The newly disclosed material follows the basic outline of what was already known about aviation failings, including that the FAA had ample reason to suspect that al-Qaida might try to hijack an airliner yet did little to deter it. But it also adds significant new details about the nature and specificity of federal aviation warnings over the years, security lapses by the federal government and the airlines, and turf battles between federal agencies. Some of the details were contained in confidential bulletins circulated by the agency to airports and airlines, and some were in its internal reports.
"While we still believe that the entire document could be made available to the public without damaging national security, we welcome this step forward," the former leaders of the commission, Thomas H. Kean and Lee H. Hamilton, said in a joint statement. "The additional detail provided in this version of the monograph will make a further contribution to the public record of the facts and circumstances of the 9/11 attacks established by the final report of the 9/11 commission."