Seeing Beyond the Checkpoint

[from the archives 11/19/2012] by Joseph F. Corrao

In the Autumn, 2012 issue of General Aviation Security, we looked at why the current checkpoint-based aviation security paradigm cannot be applied successfully to general aviation.  In this issue, we broaden focus to explain why checkpoint-based security is not a formula for success in the airline world either.  We hope that GA readers will bear with this digression, recognizing that GA won't be safe from the imposition of airline-like security until security bureaucrats see beyond the checkpoint to other, better ways of enhancing aviation security.  

There are many reasons why checkpoints are a bad idea in today's world, the first of which is that they were designed a generation ago to address a threat that barely exists anymore.  Checkpoints were developed to protect airliners from hi-jackers.  Back in the day, hijackers wanted to go somewhere and get there alive; they needed a functional airplane and crew to do it.  Today's suicide terrorists are interested only in killing people; they don't care about surviving the attack.  Our current tactics no longer match the threat, a fact that creates gaping vulnerabilities.  

One obvious vulnerability is the accumulation at the checkpoint of innocent travelers, Federal officials, expensive equipment and lots of unscreened luggage.  By definition, the checkpoint separates the airport's “public area,” which anyone may enter freely, from the so-called “sterile area,” the area that is supposed to be free of non-passengers and threat objects like guns and bombs.  Without debating whether U.S.-style behavioral detection works, whether the number of dog teams is adequate or whether dogs can sense important threat objects and devices, most will agree that security in the public area is minimal at best, and mostly nonexistent in the area ahead of the public area, outside the terminal.  Background checks cannot catch a first-time terrorist, and suicide terrorists tend to have short résumés.  Besides, one doesn't need a ticket to cross the public area.  

Two years ago, on January 24, 2011, an explosion killed 35 and injured 172 in the international arrivals area of Domodedovo Airport outside Moscow.  RIA Novosti, quoted in Western media, reported that, “[t]he blast occurred when a suspected female terrorist opened a bag."  The day after the attack, Russian President Demitri Medvedev commented, “People were allowed to walk in from anywhere."  (See U.S.A.Today, 25 Jan 2011, and BBC News Europe, 25 January 2011)  Open access characterizes the public areas of airports around the world, on the departure as well as arrival sides.  

Other weaknesses of checkpoints involve space and time.  As new equipment is added to the screening process, checkpoints grow to the limit of the airport’s ability to provide space, then become increasingly crowded within inadequate footprints.  No matter how big a checkpoint gets, it takes the average passenger only so long to move across it; equipment cannot be implemented if it has a detection latency (the time required to reach an indication) much longer than the average time to traverse the checkpoint, and opportunities to use that equipment outside the checkpoint footprint are wasted.  If detection occurs in an area where passengers and Federal employees are gathered, terrorists are provided with targets of opportunity for “salvage detonation,” the use of a weapon against a target other than the intended one when detection makes use against the intended target unlikely to succeed.  Moreover, both time and tactical options to neutralize the threat following detection are minimal in the immediate area of the checkpoint.  

There is an alternative that addresses these concerns: treating aviation security as a remote sensing problem.  Implementing stand-off detection technologies throughout the passenger path from entry on airport property enables aviation security planners to use each available technology in a manner and in a space consistent with the characteristics and requirements of both the equipment and the space.  For example, passive infrared detectors coupled with intelligent video at terminal entrances can be used to tag arriving persons for subsequent secondary screening when objects are detected that block the body’s natural infra-red radiation, such as an explosive vest or other weapon hidden on the body.  The secondary screening required to clear apparent alarms can occur well before the person in question reaches the checkpoint, providing tactical options to isolate the individual and protect persons gathered at the checkpoint.  

Detection could start even earlier, when a person or vehicle approaches the airport property, using appropriate detection technology to passively scan vehicles and persons “on the fly.”  Early detection of persons and items in need of secondary screening and directing them to purpose-built secondary screening areas would dramatically accelerate operations at the checkpoint, eliminating crowds and further enhancing both security and the passenger experience.  

Benefits of approaching aviation screening as a remote sensing problem include implementation of effective detection technologies that may have longer detection latencies than can be tolerated within a checkpoint footprint; positive association of alert indications with persons or objects well before the person or object presents at the checkpoint, enabling more tactical options to neutralize threats than can be deployed effectively within or adjacent to the checkpoint footprint; intelligently guided use of secondary screening to clear or confirm the presence of threat items; and consistently fast through-put at the checkpoint.  All this adds up to better security, a better and safer traveling experience, and possibly even lower costs to government, the airport operator, and the tax- and fee-paying public.