Monday, March 14 2005 12:43 Hrs (IST) - World Time -

New York: Despite a huge investment in security, the American aviation system remains vulnerable to attack by al Qaeda and other terrorist groups who are eyeing non-commercial planes and helicopters as particularly tempting targets, according to a confidential US Government report.

Intelligence indicates that al Qaeda may have discussed plans to hijack chartered planes, helicopters and other aircraft for attacks because they are less well-guarded than commercial airliners, the New York Times reported quoting an undisclosed 24-page assessment on aviation security by the FBI and the Department of Homeland Security two weeks ago.

But commercial airliners are also "likely to remain a target and a platform for terrorists," the report says, and members of al Qaeda appear determined to study and test new American security measures to "uncover weaknesses".

The assessment, the Times notes, comes as the Bush administration, with a new intelligence structure and many new counter-terrorism leaders in place, is taking stock of terrorists' capabilities and of the country's ability to defend itself.

While Homeland Security and the FBI routinely put out advisories on aviation issues, the paper says the special joint assessment is an effort to give a broader picture of the state of knowledge of all issues affecting aviation security, officials said.