The U.S. government should focus on more efficient aviation security during times of fiscal austerity, according to a new study by the nonprofit Rand research organization. The “Efficient Aviation Security” report, released on August 21, focuses on the costs and the benefits of aviation security in the U.S. in the post 9/11 era. “To make rational security decisions, the benefits of a measure (or group of measures) must be compared with its varied costs to determine whether those benefits exceed the cost,” the authors conclude.

Despite the organizational changes implemented after the Sept. 11, 2001 terrorist attacks, in particular the formation of the cabinet-level Department of Homeland Security and its constituent agency, the Transportation Security Administration (TSA), the strategy of aviation security “since 9/11 is more similar to than different from what came before,” the report states. One important difference is that the cost of aviation security has increased significantly.

The TSA’s Fiscal Year 2013 budget request is $7.64 billion, including $5.1 billion for aviation security. The agency says it screens more than 1.7 million passengers daily at 450 airports nationwide. Last year, it detected 1,100 firearms in carry-on bags at security checkpoints. While the line-item costs of security to government, as well as to airlines and airports, can be measured, other, intangible costs can be greater than the measured costs of security measures, according to the Rand report. It cites an International Air Transport Association estimate that security delays cost airlines and passengers $7.4 billion annually. In the past decade, it has become clear that public and private-sector “tolerance for inconvenience and other security costs is not inexhaustible,” states the report.

The report uses notional values to quantify the effect of reductions in aviation system efficiency due to security measures, with no example exceeding 0.8 percent of system value. But even a small percentage reduction in system functionality equates to billions of dollars, the authors argue, when considering that the FAA has estimated the value of the aviation system and spin-off economic activity at $1 trillion annually. A percentage decline in system efficiency is substantial even when using the smaller number of total airline revenues–an estimated $175 billion in 2010, according to the Bureau of Transportation Statistics.

The Rand researchers found that “trusted traveler” expedited passenger screening programs are one way to make aviation security more efficient. “Our analysis shows that even when uncertainties are great, we can identify plausible conditions under which a trusted traveler program would reduce risk,” the authors say.