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At What Price Security?

Even if the technical and social challenges posed by the new technologies can be resolved, costs will have to come down. Most of the detection machines sell for several hundred thousand dollars apiece. Various estimates put the cost to deploy bag scanners alone at the 75 busiest U.S. airports at about $2 billion. That’s four times the $500 million in profit the U.S. commercial carriers made in 1995, according to the FAA’s Malotky. If a gauntlet were used, the tab would be much higher. And there would still be 300 more airports to go.

Operational costs could be even greater. If slow throughput, false alarms, and bag matching lengthen preboarding time, each airline will schedule fewer flights per day, slowing down the air transportation system. “There are huge feedback effects for even a slight added delay,” says Robert Hahn, a regulatory economist at the American Enterprise Institute in Washington, D.C., and author of Risks, Costs, and Lives Saved (Oxford University Press, 1996). According to the Wall Street Journal, an internal Northwest study concluded that bag matching would add 10 minutes to processing time, a delay that would force the airline to cut its schedule by around 10 percent.

Delay would also hurt the U.S. economy. Adding a half-hour to preboarding time would cost almost $10 billion annually in lost productivity, according to Hahn.

Airports would be pinched, too. More than half of an airport’s revenue comes from parking and concessions. “More floor space for detection machines means fewer coffee bars,” says Malotky, “and longer lines for security checks mean fewer people will have time to buy coffee.” Gateways at older airports, already cramped, would have to be expanded and reinforced to support the big, heavy new machines.

All these numbers raise a bald question: Is the price worth paying to save precious, but few, lives?

In the past 15 years-a time frame that economist Hahn picks more or less arbitrarily-548 people have died in U.S. airline crashes linked to sabotage (nearly half on Pan Am 103). Dividing this number into the $2 billion needed for bag scanners alone yields a capital cost of $54 million per life saved-if, indeed, the technology could cut bombings to zero.

Whether this is a “good” investment is a distasteful question, but one that government must ask all the time. The money could be used to make safer highways, which are 20 times more dangerous per mile than air travel, according to federal estimates. “We should think about what we’re getting for the money,” Hahn argues.

Several years ago, the FAA analyzed the idea of requiring children under age two to fly in car seats-instead of sitting on a parent’s lap-forcing parents to buy another ticket, then averaging $400. The study showed that more families would drive, which would result in more highway fatalities than the in-flight car seats would save, says Malotky.

In analyzing such tradeoffs, experts are reluctant to quantify how “good” or “bad” the nation’s security is. Malotky did say that in the last few years, the airlines have found “fewer than 10” bombs or suspect weapons. Presumably some were missed. Though 100 percent detection is statistically impossible, the process can always improve. But the cost-benefit relationship may run up against diminishing returns. Malotky says if going from 90 to 95 percent detection would cost x dollars, improving from 95 to 98 percent would cost x dollars again. Economist Hahn concludes that “all this new technology would reduce the risk of death by only a very small amount.”

The FAA is now developing a cost-benefit analysis. For the time being, Malotky will say only that “if a bombing were to occur every six months, the cost-benefit would certainly make sense. If a bombing took place once every 10 years, it would not make sense.” Assuming that terrorism didn’t cause the TWA Flight 800 disaster, then the last U.S. airline bombing was Pan Am Flight 103 in 1988. “Despite all the headlines, the chance of getting blown out of the sky is vanishingly small,” says George Swenson, professor emeritus of electrical and computer engineering at the University of Illinois and chair of the NRC panel on passenger screening.

Whether heightened security is worth the cost comes down to whether the public perceives a real threat. No one has surveyed passengers to see how they feel.

Still, the technology has intrinsic value as a deterrent. Fighting terrorism is an endless game of threats and countermeasures. “We have no idea how many terrorists have been deterred because they were afraid they’d get caught,” says MIT’s Grodzins. “Personally, I’d love to see more bomb-sniffing dogs out there. Nothing is more directly worrisome to a would-be bomber.”

Unfortunately, dogs are worrisome to travelers as well. Security experts acknowledge the public’s reservations about the military atmosphere that canine teams impart, and about the prospect of being sniffed in sensitive areas by a high-strung Doberman. Dogs also cannot keep up with a systematic, 450-bag-per-hour search regimen. So even though the October 9 legislation encourages the FAA to add as many as 100 canine teams to airports nationwide, it is unclear whether this approach will be a viable substitute for new high-tech detection schemes.

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