A Strange Factoring

Air Safety Week, Jan 22, 2007

The FAA Calculates Savings From Terror-Proofing Airliners

The FAA has proposed a novel set of regulations intended to make new airliners less susceptible to terrorist attacks. If enacted, the rules would require manufacturers to incorporate stronger cockpit bulkheads and better fire suppression systems into new designs.

The FAA is portraying the initiative as a logical sequitur to the emergency April 2003 deadlined measures of reinforced and locked cockpit doors. Neither Airbus nor Boeing seemed overly enthused about the prospect of adding weight and complexity to their new designs and averred that they would have to closely study the proposition before commenting.

Cost estimates include the expense of getting the required changes approved and manufactured, and the extra fuel usage incurred by increased airplane weight. In its usual statistical foray into never-never land, the FAA claims its proposal would cost $453.9 million to implement the changes through 2049, but that those costs would be offset, the FAA believes, by a savings of $1.2 billion should the systems ever actually thwart a terrorist attack.

The proposal assumes one attack within that period, a figure based on historical data. Some of the premises and the cost-benefit equation would seem to be a little airy-fairy. It's suggested that reinforced cockpit door standards, implemented in 2003, should be extended to include the entire cockpit bulkhead, as well as the floors and ceilings of flightdecks on aircraft with more than one deck.

One major preoccupation is with reducing the areas within (or behind or under) which a device could be secreted before or during flight. Toilet flushing is also to be redesigned to make it unlikely that a device could be flushed into a holding tank.

Areas also have to be made easily searchable with a very high probability of detecting any foreign objects. That is one proviso that could be made simpatico with increasing the ease with which an inflight firefighter could get to the seat of smoke and fire - particularly in respect of electrical fires.

As well as the pilots' protection from determined intruders, cargo compartments will need to be reinforced against the detonation of explosive or incendiary devices and penetration by projectiles. Smoke removal or dispersion enhancements sufficient to avoid crew or passenger incapacitation will also be de rigeur. Cargo bay fire suppression systems must survive an explosion and continue working. This can be done by remoting the agent's storage container.

Attention will be required to determine a qualified replacement for Halon gas fire extinguishant, as it's hostile to the ozone layer, banned and no longer able to be manufactured. Redundant (and separated) normal and backup flight critical systems will be needed to maximize the potential for surviving an explosion or fire. Aircraft will need what the FAA has called a confidential "least risk bomb location" onboard - a place to where any device found can readily be moved, so that in the event of detonation, it will cause the least damage to the structure.

The FAA suggests that "reducing or eliminating differential cabin pressure markedly reduces the damage explosive devices could cause to airplane structures." It's alternatively suggested (by ASW) that the same simple mechanism used for firing sonobuoys from pressurized Maritime Patrol aircraft at high altitude could be used to jettison such devices.

The NPRM stops short of describing the prospect as being comparable to armor-plating a war-plane, but the parallels are clearly there. It's uncertain whether the measures will be as effective against an external MANPADS shoulder- fired missile attack, or even intended to partly mitigate such an event (see sidebar). Perhaps external armor-cladding will ultimately be required for that contingency.

The notice discusses six pending and synergetic advisory circulars (ACs) and probable changes to two existing ACs. The proposal is open for industry and public comment until April 5, after which the FAA will decide when the changes will take effect for new commercial aircraft with more than 60-seats or with a maximum take-off weight of 45,000kg.

MANPADS Popular On Black Market

The black market is beginning to fill with shoulder-fired missiles (MANPADS), and concern is growing so much that the U.S. Department of Homeland Security is nearly doubling its spending on counter-measures research to $110 million this year. One focus is on Skyguard, a Northrop Grumman airport device packed inside a unit and stationed hard by runways.

Described by the company as a giant laser gun with brains, Skyguard focuses an energy beam with pinpoint accuracy, heating up the explosives, detonating them prematurely. The cost is about $150 million but with large-scale production could come down to $30 million. It could be deployed at major U.S. airports by 2008 and would be far easier than equipping the commercial fleet with airborne anti-missile systems.