Aviation Security: TSA's Staffing Allocation Model Is Useful for Allocating Staff among Airports, but Its Assumptions Should Be Systematically Reassessed

A letter report issued by the Government Accountability Office with an abstract that begins "Over 600 million people travel by air each year in the United States, and the screening of airline passengers and their carry-on and checked baggage is vital to securing our transportation security system. The Aviation and Transportation Security Act, enacted in November 2001, established the Transportation Security Administration (TSA) and significantly changed how passenger and checked baggage screening is conducted in the United States. This act removed screening responsibility from air carriers and the contractors who conducted screening for them, and placed this responsibility with TSA. As a result, TSA hired and deployed about 55,000 federal passenger and baggage Transportation Security Officers (TSO)--formerly known as screeners--to more than 400 airports nationwide based largely on the number of screeners that the air carrier contractors had employed. Since August 2002, however, TSA has been statutorily prohibited from exceeding 45,000 full-time equivalent positions available for screening. The Intelligence Reform and Terrorism Prevention Act of 2004, enacted in December 2004, required TSA to develop and submit to the Senate Committee on Commerce, Science, and Transportation, and the House of Representatives Committee on Transportation and Infrastructure, standards for determining the aviation security staffing for all airports at which TSA provides or oversees screening services by March 2005. These standards are to provide the necessary levels of aviation security and ensure that the average aviation security related delay experienced by passengers is minimized. TSA submitted these standards, which form the basis of TSA's Staffing Allocation Model on June 22, 2005. The purpose of this optimization model, as identified by TSA, is to estimate the most efficient balance of TSOs needed to ensure security and minimize wait times. Models, in general, are expected to approximate the real world. These approximations must be validated to assure model users that their predictions are credible within the bounds of specific situations, environments, and circumstances. The Intelligence Reform and Terrorism Prevention Act also mandated that we conduct an analysis of TSA's staffing standards. In particular, the congressional committees to which TSA submitted the staffing standards were interested in how TSA is using the Staffing Allocation Model to identify the number of TSOs needed across the more than 400 commercial airports and how the model ensures that TSA has the right number of TSOs at the right checkpoints at the right times. This report addresses the following questions: (1) How does TSA ensure that its Staffing Allocation Model provides a sufficient number of TSOs to perform passenger and checked baggage screening at each airport and what challenges has it faced while implementing the model? (2) How does TSA deploy its TSO allocation and what factors affect the model's effectiveness in helping TSA accomplish this deployment?