Big US aviation security proposals not sure thing

WASHINGTON, June 5 (Reuters) Airlines and airports remain prime targets for extremists nearly 6 years after the September 11, 2001 terror attacks, but the US government has yet to determine whether sweeping security proposals could ever be put into practice.

Authorities were quick this week to note that an alleged plot to blow up a fuel line to New York's John F Kennedy airport was disrupted by good intelligence and effective investigation.

Homeland security planners prefer to emphasize those methods over expensive passenger and bag screening, and other touted initiatives that remain unfinished because of costs, politics or public outcry.

Since 2004, the government has spent 20 billion dollars on aviation security, much of it for maintaining a force of 40,000 screeners and related equipment to check passengers and their bags for bombs or other weapons. There is no expectation the price tag will go down any time soon.

''It's clear that al Qaeda and other extremists still remain very attracted to the aviation sector and the idea of exploiting that sector in a strike against us,'' said William Knocke, spokesman for the US Homeland Security Department.

The threat level for aviation remains at orange, the second-highest alert status.

Private experts, industry officials, government planners, and Congress have wrestled with priorities since initial steps to secure both aircraft and airports after the attacks -- which killed almost 3,000 people in New York City, Washington and Pennsylvania.

BIG IDEAS Powerful interests, including members of the US House of Representatives and Senate, continue to push for advanced bag screening, estimated to cost 22 billion dollars over 20 years, and a response to one of the most alarming scenarios -- the threat to commercial aircraft of shoulder-fired missiles.

Raytheon Co, Northrop Grumman Corp and Britain's BAE Systems are researching and testing whether military technologies could protect passenger jets from missiles.

There have been several missile attempts on airliners, including one by an al Qaeda-linked group on an Israeli plane over Kenya in 2002. There have been no such attempt in the United States.

Northrop has installed an infrared antimissile system on six planes and plans to outfit three more by the end of this month.

Cost estimates vary, depending on the number of aircraft and what group is calculating the estimate. But airlines have resisted the option over the projected multibillion-dollar expense, complexity and indecision over who would pay for it. There are roughly 4,300 jetliners operated by major US airlines.

''Our position has been that there needs to continue to be a layered approach to aviation security. It has to be practical,'' said David Castelveter, a spokesman for the chief trade group of major US airlines, the Air Transport Association.

The Bush administration will report to Congress on what approach might hold the most promise for missiles. In addition to completing tests this year on countermeasures placed on aircraft, the Homeland Security Department and contractors are studying the feasibility of using unmanned Drones to shoot down missiles and weighing ground-based alternatives that would detect a launch and intercept missiles.

''To this point, there hasn't been an incident that has concerned the folks that make these kind of decisions to the point that they would like to see the program accelerated,'' said Jack Pledger, director of infrared countermeasures business development at Northrop.

In fact, the agency may never wind up mandating a solution unless ordered by Congress, suggesting the possibility that airlines, airports and contractors would have to decide what to do, if anything.

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