United States Government Accountability Office

GAO Testimony before the Subcommittee on 

Aviation, Committee on Transportation 

and Infrastructure, House of 

Representatives

AVIATION SECURITY

TSA Has Strengthened 

Efforts to Plan for the 

Optimal Deployment of 

Checked Baggage Screening 

Systems, but Funding 

Uncertainties Remain 

Statement of Cathleen A. Berrick, Director 

Homeland Security and Justice Issues 

For Release on Delivery

Expected at 10:00 a.m. EDT 

Thursday, June 29, 2006

 

GAO-06-875T 
What GAO Found

United States Government Accountability Office

Why GAO Did This Study

Highlights

Accountability Integrity Reliability

June 29, 2006

AVIATION SECURITY

TSA Has Strengthened Efforts to Plan for 

the Optimal Deployment of Checked 

Baggage Screening Systems, but 

Funding Uncertainties Remain 

Highlights of GAO-06-875T, a testimony 

before the Subcommittee on Aviation, 

Committee on Transportation and

Infrastructure, House of Representatives 

The Transportation Security 

Administration (TSA) has deployed

two types of baggage screening

equipment: explosive detection 

systems (EDS), which use X-rays to

scan bags for explosives, and 

explosive trace detection systems

(ETD), in which bags are swabbed 

to test for chemical traces of

explosives. TSA considers 

screening with EDS to be superior 

to screening with ETD because

EDS machines process more bags 

per hour and automatically detect 

explosives without direct human 

involvement. In March 2005, GAO

reported that while TSA had made

progress in deploying EDS and

ETD machines, it had not 

conducted a systematic,

prospective analysis of the optimal 

deployment of these machines to

achieve long-term savings and 

enhanced efficiencies and security. 

GAO’s testimony today updates our

previous report and discusses 

TSA’s (1) deployment of EDS and 

ETD systems and the identified

benefits of in-line systems, and (2)

planning for the optimal 

deployment of checked baggage 

screening systems and efforts to 

identify funding and financing 

options. 

What GAO Recommends

GAO previously recommended that

TSA systematically evaluate

checked baggage screening needs

at airports, such as identifying the 

costs and benefits of installing inline systems or stand-alone EDS.

DHS generally concurred with our 

recommendations. 

Since its inception in November 2001 through June 2006, TSA has procured 

and installed about 1,600 EDS machines and 7,200 ETD machines to screen 

checked baggage for explosives at over 400 airports. However, initial

deployment of EDS machines in a stand-alone mode—usually in airport 

lobbies—and ETD machines resulted in operational inefficiencies and 

security risks as compared with using EDS machines integrated in-line with 

airport baggage conveyor systems. For example, TSA’s use of stand-alone 

EDS and ETD machines required a greater number of screeners and resulted 

in screening fewer bags for explosives each hour. In March 2005, we 

reported that at nine airports where TSA has agreed to help fund the 

installation of in-line EDS systems, TSA estimated that screening with in-line 

EDS machines could save the federal government about $1.3 billion over 7 

years. In February 2006, TSA reported that many of the initial in-line EDS 

systems did not achieve the anticipated savings. However, recent 

improvements in the design of the in-line EDS systems and EDS screening 

technology now offer the opportunity for higher-performance and lower-cost 

screening systems. Finally, screening with in-line EDS systems may result in 

security benefits by reducing the need for TSA to use alternative screening 

procedures, such as screening with explosives detection canines and 

physical bag searches, which involve trade-offs in security effectiveness. 

TSA has begun to systematically plan for the optimal deployment of checked 

baggage screening systems, but resources have not been made available to 

fund the installation of in-line EDS systems on a large-scale basis. In 

February 2006, TSA released its strategic planning framework for checked 

baggage screening aimed at increasing security through deploying more EDS 

machines, lowering program life-cycle costs, minimizing impacts to TSA and 

airport and airline operations, and providing a flexible security

infrastructure. As part of this effort, TSA identified the 25 airports that 

should first receive federal funding for the installation of in-line EDS 

systems, and the optimal checked baggage screening solutions for the 250

airports with the highest checked baggage volumes. In February 2006, TSA 

estimated that installing and operating the optimal checked baggage 

screening systems will cost about $22.4 billion over 20 years and reported 

that under current investment levels, installation of optimal baggage 

screening systems would not be completed until approximately 2024. TSA is 

collaborating with airport operators, airlines, and other key stakeholders to 

identify funding and cost sharing strategies and is focusing its research and 

development efforts on the next generation of EDS technology. 

EDS and ETD Machines Used by TSA to Screen Checked Baggage 

www.gao.gov/cgi-bin/getrpt?GAO-06-875T.

To view the full product, including the scope 

and methodology, click on the link above. 

For more information, contact Cathleen A. 

Berrick at (202) 512-3404 or

berrickc@gao.gov. 
This is a work of the U.S. government and is not subject to copyright protection in the 

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reproduce this material separately. 
Mr. Chairman and Members of the Subcommittee: 

I appreciate the opportunity to participate in today’s hearing on the status

of the Transportation Security Administration’s (TSA) efforts to deploy 

checked baggage screening technology to the nation’s commercial 

airports, and to discuss our work in this area. As you know, after the 

terrorist attacks of September 11, 2001, which highlighted the vulnerability 

of U.S. aircraft to acts of terrorism, Congress passed and the President 

signed into law, the Aviation and Transportation Security Act (ATSA), 

creating the TSA and mandating, among other things, that all checked

baggage at U.S. airports be screened using explosive detection systems by 

December 31, 2002.1

 To meet this requirement, TSA deployed two types of 

equipment to screen checked baggage for explosives: (1) explosives 

detection systems (EDS) that use specialized X-rays to detect 

characteristics of explosives that may be contained in baggage as it moves 

along a conveyor belt and (2) explosive trace detection (ETD) systems, 

whereby a Transportation Security Officer (TSO) swabs baggage and then 

inserts the swab into the ETD machine, which in turn can detect chemical

residues that may indicate the presence of explosives within a bag. 

In November 2002, Congress passed, and the President signed into law, the

Homeland Security Act of 2002, which, in effect, extended the deadline for 

screening all checked baggage for explosives until December 31, 2003, for 

airports at which TSA was unable to meet the earlier deadline established 

by ATSA.2 In March 2005, we reported that largely because of shortages of 

equipment and insufficient time to modify airports to accommodate EDS 

machines, TSA had been unable, at certain airports, to meet the 2002 

congressionally established deadline to screen all checked baggage for 

explosives using explosive detection systems.3

 We also reported that at

most smaller airports, where EDS machines are not installed, TSA screens 

solely with ETD machines. Further we reported that while TSA had made 

progress in deploying EDS and ETD machines, it had not conducted a 

systematic, prospective analysis of the optimal deployment of these 

machines to achieve long-term savings and enhanced efficiencies and 

 1

Aviation and Transportation Security Act, Pub. L. No. 107-71, 115 Stat. 597 (2001). See 49 

U.S.C. §§ 114(a), 44901(d)(1). 

2

Homeland Security Act of 2002, Pub. L. No. 107-296, 116 Stat. 2135. See 49 U.S.C. § 

44901(d)(2). 

3

GAO, Aviation Security: Systematic Planning Needed to Optimize the Deployment of 

Checked Baggage Screening Systems, GAO-05-365 (Washington, D.C.: March 15, 2005). 

Page 1 GAO-06-875T 
security. Finally, in February 2006, we reported that TSA considers 

screening with EDS to be superior to screening with ETD because EDS 

machines process more bags per hour and automatically detect explosives 

without direct human involvement.4

My testimony today updates the information we reported in March 2005,

and discusses (1) TSA’s deployment of EDS and ETD systems and the 

identified benefits of installing in-line checked baggage screening systems 

at airports and (2) TSA’s efforts to plan for and identify funding options for 

the optimal deployment of EDS and ETD equipment, including in-line 

checked baggage screening systems. My comments are based on issued 

GAO reports and testimonies addressing TSA’s checked baggage screening

program and our review of TSA documents related to the deployment of 

checked baggage screening systems, including TSA’s February 2006 

strategic planning framework for its checked baggage screening program.5

We conducted our work in accordance with generally accepted 

government auditing standards. Appendix I contains a list of related GAO 

products issued on TSA’s checked baggage screening program. 

Since its inception in November 2001 through June 2006, TSA has 

procured and installed about 1,600 EDS machines and about 7,200 ETD 

machines to screen checked baggage for explosives at over 400 

commercial airports. However, initial deployment of EDS machines in a 

stand-alone mode—usually in airport lobbies—and ETD machines resulted 

in operational inefficiencies and security risks as compared with using 

EDS machines integrated in-line with airport baggage conveyor systems. 

For example, TSA’s use of stand-alone EDS and ETD machines required a 

greater number of screeners and resulted in screening fewer bags for 

explosives each hour. Additionally, because in-line EDS checked baggage 

screening systems can significantly reduce the need for TSOs to handle 

baggage, installing them may also reduce the number of TSO on-the-job 

injuries. In March 2005, we reported that at nine airports where TSA has 

agreed to help fund the installation of in-line EDS systems, TSA estimated 

that screening with in-line EDS machines could save the federal 

Summary 

 4

 GAO, Aviation Security: TSA Management of Checked Baggage Screening Procedures 

Could Be Improved; GAO-06-291SU (Washington, D.C.: February 28, 2006).

5

Although we could not independently verify the reliability of all of the information we 

obtained, we compared it with other supporting documents, when available, to determine 

data consistency and reasonableness. 

Page 2 GAO-06-875T 
government about $1.3 billion over 7 years. In February 2006, TSA 

reported that a savings of approximately $4.7 billion could be realized over 

a period of 20 years by installing optimal checked baggage screening 

systems, including in-line EDS machines, at the airports with the highest 

checked baggage volumes. However, TSA also reported in February 2006 

that many of the initial in-line EDS systems did not achieve the degree of 

anticipated savings initially estimated. TSA has since determined that 

recent improvements in the design of the in-line EDS systems and EDS 

screening technology now offer the opportunity for higher performance 

and lower cost screening systems. Screening with in-line EDS systems 

could also result in security benefits by reducing congestion in airport 

lobbies and reducing the need for TSA to use alternative screening 

procedures, such as screening with explosives detection canines and 

physical bag searches. TSA’s use of these procedures, which are only to be

used when volumes of baggage awaiting screening pose security 

vulnerabilities or when TSA officials determine that there is a security risk 

associated with large concentrations of passengers in an area, has 

involved trade-offs in security effectiveness.6

TSA has begun to systematically plan for the optimal deployment of 

checked baggage screening systems, but resources have not been made 

available to fund the installation of in-line EDS machines on a large-scale 

basis. In February 2006, TSA released its strategic planning framework for 

checked baggage screening aimed at increasing security through deploying 

more EDS machines, lowering program life-cycle costs, minimizing 

impacts to TSA and airport and airline operations, and providing a flexible 

security infrastructure. According to TSA, the framework will be used to 

establish a comprehensive strategic plan for TSA’s checked baggage 

screening program. TSA expects to complete the strategic plan in early fall

2006. As part of this planning effort, TSA identified, among other things, 

the top 25 airports that should first receive federal funding for projects 

related to the installation of in-line EDS systems, and the optimal checked 

baggage screening solutions for the 250 airports with the highest checked

baggage volumes. In June 2006, TSA officials reported that if the top 25

airports do not receive in-line checked baggage screening systems, they 

will require additional screening equipment to be placed in airport lobbies 

and additional TSO staffing in order to remain in compliance with the 

 6

Certain information we obtained and analyzed regarding explosives detection technologies

and their effectiveness in TSA’s checked baggage screening operations are classified or are 

considered by TSA to be sensitive security information. Accordingly, the results of our

review of this information have been removed from this testimony. 

Page 3 GAO-06-875T 
mandate for screening all checked baggage using explosive detection 

systems. In February 2006, TSA estimated that the total cost of installing 

and operating the optimal checked baggage screening systems at the 

250 airports is approximately $22.4 billion over 20 years, of which about 

$6 billion is for installation, life-cycle replacement, existing committed 

funding, and equipment maintenance costs. However, insufficient 

resources have been made available to fund in-line systems on a large 

scale basis. TSA currently uses annual appropriations and a mandatory 

appropriation from the Aviation Security Capital Fund to fund the 

construction of in-line baggage screening systems.7

 Further, in order to 

leverage federal and private sector resources, TSA has supported the 

construction of in-line systems at 9 airports through letter of intent 

agreements.8 TSA reported that as of June 2006, 25 airports had 

operational in-line EDS systems and an additional 24 airports had in-line 

systems under development.9

 In May 2006, TSA reported that under 

current investment levels, installation of optimal checked baggage

screening systems would not be completed until approximately 2024. TSA

is currently collaborating with airport operators, airlines, and other key 

stakeholders to identify funding and cost-sharing strategies—an effort that 

TSA expects to complete by early fall 2006. TSA is also focusing its 

research and development efforts on the next generation of EDS 

technology.

Prior to the passage of ATSA in November 2001, only limited screening of

checked baggage for explosives occurred. When this screening took place, 

air carriers had operational responsibility for conducting the screening, 

while the Federal Aviation Administration (FAA) maintained oversight 

responsibility. With the passage of ATSA, TSA assumed responsibility for 

ensuring that all checked baggage is properly screened for explosives at 

airports in the United States where screening is required, and for the 

procurement, installation, and maintenance of explosive detection systems 

used to screen checked baggage for explosives. Airport operators and air

Background 

 7

Airports also rely on nonfederal sources of funding to fund in-line EDS systems. 

8

A letter of intent, though not a binding commitment of federal funding, represents an

intent by TSA to provide future years funding in support of a project, contingent upon the

availability of appropriated funds. 

9

The in-line systems were either airportwide (full) or at a particular terminal or terminals 

(partial). 

Page 4 GAO-06-875T 
carriers continued to be responsible for processing and transporting 

passenger checked baggage from the check-in counter to the airplane. 

Explosive detection systems used to screen checked baggage include EDS 

and ETD machines. EDS machines, which cost between about $300,000 

and $1.2 million each, use computer-aided tomography X-rays adapted

from the medical field to examine the objects inside baggage to 

automatically recognize the characteristic signatures of threat explosives. 

TSA has certified, procured, and deployed EDS machines made by three 

manufacturers. ETD machines, which cost approximately $40,000 to 

$50,000 each, work by detecting vapors and residues of explosives. 

Because human operators collect samples by rubbing bags with swabs, 

which are then chemically analyzed in the ETD machines to identify any 

traces of explosive materials, the use of ETD is more labor-intensive and

subject to more human error than the automated process of using EDS 

machines. ETD is used for both primary, or the initial, screening of 

checked baggage, and secondary screening, which resolves alarms from 

EDS machines that indicate the possible presence of explosives inside a 

bag. 

As we reported in March 2005, to initially deploy EDS and ETD equipment 

to screen 100 percent of checked baggage for explosives, TSA 

implemented interim airport lobby solutions and in-line EDS baggage 

screening systems.10 The interim lobby solutions involved placing standalone EDS and ETD machines in the nation’s airports, most often in 

airport lobbies or baggage makeup areas where baggage is sorted for 

loading onto aircraft. For EDS in a stand-alone mode (not integrated with 

an airport’s or air carrier’s baggage conveyor system) and ETD, TSA TSOs 

are responsible for obtaining the passengers’ checked baggage from either 

the passenger or the air carrier, lifting the bags onto and off of EDS 

machines or ETD tables, using TSA protocols to appropriately screen the 

bags, and returning the cleared bags to the air carriers to be loaded onto 

departing aircraft. In addition to installing stand-alone EDS and ETD 

machines in airport lobbies and baggage makeup areas, TSA collaborated 

with some airport operators and air carriers to install integrated in-line 

EDS baggage screening systems within their baggage conveyor systems. 

In March 2005, we reported that TSA used most of its fiscal year 2002 

through 2004 checked baggage screening program funding to design, 

 10GAO-05-365. 

Page 5 GAO-06-875T 
develop, and deploy interim lobby screening solutions rather than install 

more permanent in-line EDS baggage screening systems. We also reported 

that during our site visits to 22 category X, I, and II airports,11 we observed 

that in most cases, TSA used stand-alone EDS machines and ETD 

machines as the primary method for screening checked baggage.12

Generally, this equipment was located in airport lobbies and in baggage 

makeup areas. In addition, in our survey of 155 federal security directors,13

we asked the directors to estimate, for the 263 airports included in the 

survey, the approximate percentage of checked baggage that was screened 

on or around February 29, 2004, using EDS, ETD, or other approved 

alternatives for screening baggage such as screening with explosives 

detection canines, and physical bag searches. As shown in table 1, the 

directors reported that for 130 large to medium-sized airports in our 

survey (21, 60, and 49 category X, I, and II airports, respectively), most of 

the checked baggage was screened using stand-alone EDS or ETD 

machines. On average, the percentage of checked baggage reported as 

screened using EDS machines at airports with partial or full in-line EDS 

capability ranged from 4 percent for category II airports to 11 percent for 

category X airports. In addition, the directors reported that ETD machines 

were used to screen checked baggage 93 to 99 percent of the time at 

category III and IV airports, respectively. 

 11TSA classifies the over 400 airports in the United States into one of five categories—X, I,

II, III, and IV. Generally, category X airports have the largest number of passenger 

boardings and category IV airports have the smallest number. 

12The 22 airports included 12 category X, 9 category I, and 1 category II airports. We 

conducted our site visits between September 2003 and March 2004. 

13 The federal security directors are the ranking TSA authorities responsible for the 

leadership and coordination of TSA security activities at the nation’s commercial airports.

Page 6 GAO-06-875T 
Table 1: Average Percentage of Checked Baggage Reported as Screened Using EDS, ETD, or Other Approved Method at 263 

Airports on or around February 29, 2004 

Airport category X I II III IV Total

Number of airports 21 60 49 73 60 263

Percentage of checked baggage screened using

EDS (at airports with no in-line EDS capability) 59 59 27 6 0 25

EDS (at airports with partial or airportwide in-line EDS capability) 11 8 4 0 0 3

Totala EDS 70 67 32 6 0 28

ETD 18 33 66 93 99 69

Totala EDS and ETD 88 99 98 99 99 98

Other approved method 12 1 2 2 1 2

Totala 100 100 100 100 100 100

Source: analysis of GAO federal security director survey data. 

a

Percentages in totals may not add to 100 percent because of rounding. 

The Deployment of 

Stand-alone Explosive 

Detection Systems 

Led to Operational 

Inefficiencies and 

Security Risks that InLine Systems Could 

Address at Some 

Airports 

Stand-alone Checked 

Baggage Screening 

Systems Created 

Operational Inefficiencies 

and Security Risks 

Since its inception in November 2001 through June 22, 2006, TSA has 

procured and installed about 1,600 EDS machines and about 7,200 ETD 

machines to screen checked baggage for explosives at over 400 

commercial airports. For the most part, TSA deployed EDS machines at 

larger airports and ETD machines at smaller airports, resulting in primary 

screening being conducted solely with ETD machines at over 300 airports. 

TSA installed ETD machines instead of EDS for primary screening at these 

airports because of the configuration of screening stations, the costs 

associated with procuring EDS, and the low passenger volume at smaller 

Page 7 GAO-06-875T 
airports. Table 2 summarizes the location of EDS and ETD equipment at 

the nation’s airports by airport category as of June 22, 2006.

Table 2: EDS and ETD Machines Deployed at U.S. Airports as of June 22, 2006 

Number 

Airport category Airports EDS machines ETD machines

X 27 1,019 3,439

I 55 468 1,969

II 73 104 889

III 116 29 607

IV 176 7 432

Total 447 1,627 7,336

Source: GAO analysis of TSA data. 

Stand-alone EDS and ETD machines are both labor- and time-intensive to 

operate since each bag must be physically carried to an EDS or ETD 

machine for screening and then moved back to the baggage conveyor 

system prior to being loaded onto an aircraft. With an in-line EDS system,

checked baggage is screened within an airport’s baggage conveyor system, 

eliminating the need for a TSO or other personnel to physically transport 

the baggage from the check-in point to the EDS machine for screening and 

then to the airport baggage conveyor system. Further, according to TSA 

officials, ETD machines and stand-alone EDS machines are less efficient in

the number of checked bags that can be screened per hour per machine 

than are EDS machines that are integrated in-line with the airport baggage 

conveyor systems. According to TSA estimates, the number of checked 

bags screened per hour can more than double when EDS machines are 

placed in-line versus being used in a stand-alone mode. Table 3 identifies 

TSA’s estimates for bags screened per hour by EDS machines in standalone and in-line configurations and ETD machines. 

Page 8 GAO-06-875T 
Table 3: Estimated Bags Per Hour Screened by Stand-alone and In-line EDS 

Machines and ETD Machines

Bags per hour

Type of equipment Stand-alone In-line

EDS machines

CTX 2500—stand-alone only 120 NA

CTX 5500 180 250

CTX 9000—in-line only NA 500

L3 6000 140 500

Reveal CT-80 80 NA

ETD machines—stand-alone only 36 NA

Source: TSA. 

NA: Not applicable. 

In-Line Systems Have 

Efficiency, Safety, and 

Security Benefits 

TSA has reported that in-line systems create significant efficiency benefits. 

In January 2004, TSA, in support of its planning, budgeting, and acquisition 

of security screening equipment, reported to the Office of Management 

and Budget (OMB) that the efficiency benefits of in-line rather than standalone EDS were significant, particularly with regard to bags per hour 

screened and the number of TSOs required to operate the equipment. 

According to TSA officials, at that time, a typical lobby-based screening 

unit consisting of a stand-alone EDS machine with three ETD machines 

had a baggage throughput (bags screened per hour) of 376 bags per hour 

with a staffing requirement of 19 TSOs. In contrast, TSA estimated that 

approximately 425 bags per hour could be screened by an in-line EDS 

machine with a staffing requirement of 4.25 TSOs. 

In order to achieve the higher throughput rates and reduce the number of 

TSOs needed to operate in-line baggage screening systems, TSA (1) uses a 

screening procedure known as on-screen alarm resolution and 

(2) networks multiple in-line EDS machines together, referred to as 

multiplexing, so that the computer-generated images of bags from these 

machines are sent to a central location where TSOs can monitor the 

images of suspect bags centrally from several machines using the onPage 9 GAO-06-875T 
screen alarm resolution procedure.14 A TSA official estimated that the onscreen alarm resolution procedure with in-line EDS baggage screening 

systems would enable TSA to reduce the number of bags requiring the 

more labor-intensive secondary screening using ETD machines by 40 to 

60 percent. In estimating the potential savings in staffing requirements, 

TSA officials stated that they expect to achieve a 20 to 25 percent savings 

because of reductions in the number of staff needed to screen bags using 

ETD to resolve alarms from in-line EDS machines. According to TSA 

officials, as of June 22, 2006, all airports with EDS equipment use onscreen alarm resolution protocols and 16 airports had networked in-line 

systems. 

In May 2004, TSA conducted a limited, retrospective cost-benefit analysis 

at the nine airports that signed letter of intent (LOI) agreements and found 

that significant savings and other benefits could be achieved through the 

installation of these systems.15 This analysis was conducted to estimate 

potential future cost savings and other benefits that could be achieved 

from installing in-line systems instead of using stand-alone EDS systems. 

We reported in March 2005 that, according to TSA’s analysis, in-line EDS 

would reduce by 78 percent the number of TSA TSOs and supervisors 

required to screen checked baggage at these nine airports, from 6,645 to 

1,477 TSOs and supervisors. The actual number of TSOs and supervisor 

positions that could be eliminated would be dependent on the individual 

design and operating conditions at each airport. TSA estimated that in-line 

 14Under the on-screen alarm resolution procedure, when an EDS machine sets off an alarm, 

indicating the possibility that explosive material may be contained in the bag, TSOs 

examine computer-generated images of the inside of a bag to determine if suspect items 

identified by the EDS machines are in fact suspicious. If a TSO, by viewing these images, is 

able to determine that the suspect item or items identified by the EDS machine are in fact

harmless, the TSO is allowed to clear the bag, and it is sent to the airline baggage makeup 

area for loading onto the aircraft. If the TSO is not able to determine that the bag does not 

contain suspicious objects, the bag is sent to a secondary screening room where the bag is

further examined by a TSO. TSA also uses this on-screen alarm resolution procedure with

stand-alone EDS machines. 

15We reviewed the TSA cost model showing savings expected to be achieved with in-line 

rather than stand-alone EDS equipment at nine airports. We assessed the model’s logic to

ensure its completeness and correctness of calculations. Also, as discussed in appendix IV 

of our March 2005 report (GAO-05-365), we conducted a Monte Carlo simulation to: 

(1) illustrate sensitivity of potential cost savings of replacing stand-alone with in-line EDS 

systems to alternative values of key cost drivers and (2) to explore the variability in the key 

factors used by TSA in their model. On the basis of our review of TSA’s cost model, we 

believe that it is sufficiently reliable for the analyses we conducted and the information 

included in this testimony. 

Page 10 GAO-06-875T 
baggage screening systems at these airports would save the federal 

government about $1.3 billion16 compared with stand-alone EDS systems 

and that TSA would recover its initial investment in a little over 1 year.17

According to TSA’s analysis of the nine LOI airports, in-line cost savings 

critically depend on how much an airport’s facilities have to be modified 

to accommodate the in-line configuration. Savings also depend on TSA’s 

costs to buy, install, and network the EDS machines; subsequent 

maintenance costs; and the number of screeners needed to operate the 

machines in-line instead of using stand-alone EDS systems. In its analysis, 

TSA also found that a key factor driving many of these costs is 

throughput—how many bags an in-line EDS system can screen per hour 

compared with the rate for a stand-alone system. TSA’s analysis also 

provided data to estimate the cost savings resulting from installing in-line 

EDS checked baggage screening systems for each airport over the 7-year

period. According to TSA’s data, federal cost savings varied from about 

$50 million to over $250 million at eight of the nine airports, while at one 

airport, there was an estimated $90 million loss.18 

In February 2006, TSA reported that a saving of approximately $4.7 billion

could be realized over a period of 20 years by installing optimal checked 

baggage screening systems at the 250 airports with the highest checked 

baggage volumes. This savings represents the difference between TSA’s 

compliance only strategy—which assumes minimum capital expenditures 

and no additional investment in in-line systems in order to comply with the 

mandate to screen all checked baggage using explosive detection 

systems—and its preferred strategy, which is based on using optimal 

checked baggage screening systems, including in-line EDS systems, for the 

250 airports. TSA estimated that the compliance only strategy would cost 

 16This figure refers to the net present value saved over 7 years if received up front. 

17For a basis of comparison, Office of Management and Budget Circular A-94 stipulates

using a 7 percent real discount rate to compute the present value of cost savings. TSA used 

a 4 percent real discount rate. Following Office of Management and Budget guidance, cost

savings are $1.14 billion. In addition, in TSA’s analysis, the federal government does not pay

for $319 million, or 25 percent, of project costs. Accounting for these costs to reflect total 

costs, as recommended by Circular A-94, lowers overall savings to $820 million.

18The relatively large costs for up-front in-line EDS at one of the nine LOI airports were not 

offset by the modest amount of estimated operation and maintenance cost savings;

therefore, the in-line EDS system may be more costly than EDS stand-alone. By contrast, at

another one of the nine LOI airports, the up-front costs of in-line EDS are lower than for

stand-alone EDS, and there is a substantial amount of estimated operation and 

maintenance cost savings. Therefore, the in-line EDS system at this latter airport may be

less costly than stand-alone EDS. 

Page 11 GAO-06-875T 
$27.05 billion and the preferred strategy would cost $22.39 billion over 

20 years, creating a saving of $4.66 billion.19

TSA reported that many of the initial in-line systems have produced a level 

of TSO labor savings insufficient to offset up-front capital costs of 

constructing the systems. According to TSA, the facility and baggage 

handling system modification costs have been higher than expected, with 

the nine airports with LOIs having incurred or projecting to incur up to 

$6 million or more in infrastructure costs for every EDS machine required.

TSA stated that the keys to reducing future costs are establishing 

guidelines outlining best practices and a set of efficient design choices, 

and using newer EDS technology that best matches each optimally scaled 

design solution. In February 2006, TSA reported that recent improvements 

in the design of the in-line EDS checked baggage screening systems and 

the EDS screening technology now offer the opportunity for higherperformance and lower-cost screening systems. 

A safety benefit of in-line EDS systems is the potential to reduce on-the job 

injuries. TSA reported that because procedures for using stand-alone EDS 

and ETD machines require TSOs to lift heavy baggage onto and off of the 

machines, the interim lobby screening solutions used by TSA led to 

significant numbers of on-the-job injuries.20 Additionally, in responding to 

our survey about 263 airports, numerous federal security directors 

reported that on-the-job injuries related to lifting heavy baggage onto or 

off the EDS and ETD machines were a significant concern at the airports 

for which they were responsible. Specifically, these federal security 

directors reported that on-the-job injuries caused by lifting heavy bags 

onto and off of EDS machines were a significant concern at 65 airports, 

and were a significant concern with the use of ETD machines at 110

airports. To reduce on-the-job injuries, TSA has provided training to TSOs

on proper lifting procedures. However, according to TSA officials, in-line 

EDS screening systems would significantly reduce the need for TSOs to 

 19These estimates are in present value terms. TSA estimated that it would cost about $1.7

billion for the optimal systems at the 250 airports, and TSA would achieve savings of about

$6.2 billion in TSO staff savings. Additionally, TSA’s estimate identified that equipment 

maintenance and EDS equipment life cycle replacement costs would be lower (about $150 

million) under the preferred strategy. 

20 The Occupational Safety and Health Administration has projected based on the first two 

quarters of fiscal year 2006 that more than 16 percent of TSA employees will report a job 

related injury or illness by the end of the fiscal year, the highest percentage in the federal 

government.

Page 12 GAO-06-875T 
handle baggage, thus further reducing the number of on-the-job injuries 

being experienced by TSA TSOs. 

Use of in-line EDS systems can also provide security benefits at airports 

where they are installed by reducing congestion in airport lobbies and 

reducing the need for TSA to use alternative screening procedures at 

airports. During our site visits to 22 large and medium-sized airports, 

several TSA, airport, and airline officials expressed concern regarding the

security risks caused by overcrowding due to ETD and stand-alone EDS 

machines located in airport lobbies.21 The location of the equipment 

resulted in less space available to accommodate passenger movement and 

caused congestion due to passengers waiting in lines in public areas to 

have their checked baggage screened. TSA headquarters officials reported 

that large groups of people congregating in crowded airport lobbies 

increases security risks by creating a potential target for terrorists. TSA 

also reported that airports favor replacing stand-alone EDS machines with 

in-line systems to mitigate the negative effects of increased congestion and 

passenger processing times. TSA further reported that in-line systems are 

more secure than stand-alone EDS machines because the baggage 

screening is performed away from passengers who otherwise could 

tamper with the baggage.

Another potential security benefit of in-line EDS systems is the reduction 

of the need for TSA to use alternative screening procedures. In addition to

screening with standard procedures using EDS and ETD, which TSA had 

determined to provide the most effective detection of explosives, TSA also

allows alternative screening procedures to be used when volumes of 

baggage awaiting screening pose security vulnerabilities or when TSA 

officials determine that there is a security risk associated with large 

concentrations of passengers in an area. These alternative screening 

procedures include the use of EDS and ETD machines in nonstandard 

ways,22 and also include three procedures that do not use EDS or ETD—

screening with explosives detection canines, physical bag searches, and 

matching baggage to passenger manifests to confirm that the passenger 

 21 We conducted our site visits between September 2003 and March 2004. 

22The nonstandard ways that the machines are used is sensitive security information. 

Page 13 GAO-06-875T 
and his or her baggage are on the same plane.23 TSA’s use of alternative 

screening procedures has involved trade-offs in security effectiveness. 

However, the extent of the security trade-offs is not fully known because 

TSA has not tested the effectiveness of alternative screening procedures in 

an operational environment. 

As part of our ongoing work on TSA’s use of alternative screening 

procedures to screen checked baggage, we found that the superior 

efficiency of screening with in-line EDS compared to screening with standalone EDS may have been a factor in reducing the need to use alternative 

screening procedures at airports where in-line systems were installed. 

After in-line EDS systems are installed and staffing reductions are 

achieved, redistributing the screening positions to other airports with 

staffing shortages may reduce airports’ need to use alternative screening 

procedures. In addition to deploying more efficient checked baggage 

screening systems, TSA is pursuing other mitigating actions to reduce the

need to use alternative screening procedures. These factors include 

strengthening its coordination with groups such as tour operators, 

deploying “optimization teams” to airports that were frequently using 

alternative screening procedures to determine why the procedures were 

being used so often and to suggest remedies; and deploying additional 

EDS machines. 

Although TSA officials have estimated that a low percentage of checked 

baggage is currently screened using alternative screening procedures, in 

February 2006 TSA reported that the use of alternative screening 

procedures will increase at some airports because of rising passenger 

traffic. TSA has projected that the number of originating domestic and 

international passengers will rise by about 127 million passengers over 

current levels by 2010. If TSA’s current estimate of an average of 

0.76 checked bags per passenger were to remain constant through 2010, 

TSA would be screening about 96 million more bags that it now screens. 

This could increase airports’ need to rely on alternative screening 

procedures in the future in the absence of additional or more efficient EDS 

machines, including in-line EDS systems. 

 23It is TSA’s policy to use standard EDS and ETD screening procedures whenever possible 

because of legislative requirements to do so and because TSA has concluded that these 

procedures provide the most effective detection of explosives at a checked baggage 

screening station. 

Page 14 GAO-06-875T 
TSA Has Begun 

Systematically 

Planning for the 

Optimal Deployment 

of Checked Baggage 

Screening Systems, 

but It Continues to 

Face Funding 

Uncertainties 

TSA Has Made Progress in 

Planning for the Optimal 

Deployment of Checked 

Baggage Screening 

Systems 

TSA has made progress in its efforts to systematically plan for the optimal 

deployment of checked baggage screening systems, but resources have not 

been made available to fund these systems on a large-scale basis. In March 

2005, we reported that while TSA has made progress in deploying EDS and 

ETD machines, it had not conducted a systematic, prospective analysis of 

the optimal deployment of these machines to achieve long-term savings 

and enhanced efficiencies and security.24 We recommended that TSA 

assess the feasibility, expected benefits, and cost to replace ETD machines 

with stand-alone EDS machines for the primary screening of checked

baggage at those airports where in-line EDS systems would not be either 

economically justified or justified for other reasons. In February 2006, in 

response to our recommendation and a legislative requirement to submit a 

schedule for expediting the installation and use of in-line systems and 

replacement of ETD equipment with EDS machines, 25 TSA completed its 

strategic planning framework for its checked baggage screening program. 

This framework introduces a strategy intended to increase security 

through deploying in-line and stand-alone EDS to as many airports as 

practicable, lower life-cycle costs for the program, minimize impacts to 

TSA and airport/airline operations, and provide a flexible security 

infrastructure for accommodating growing airline traffic and potential new 

 24 GAO-05-365. 

25 Intelligence Reform and Terrorism Prevention Act of 2004, Pub. L. No. 108-458, § 4019(a)-

(c), 118 Stat. 3638, 3721-22. 

Page 15 GAO-06-875T 
threats. 26 The framework is an initial step in addressing the following 

areas: 

• Optimized checked baggage screening solutions—finding the ideal 

mix of higher-performance and lower-cost alternative screening 

solutions for the 250 airports with the highest checked baggage

volumes; 

• Funding prioritization schedule by airport—identifying the top 

25 airports that should first receive federal funding for projects 

related to the installation of explosive detection systems based on 

quantitative modeling of security, economic, and other factors; 

• Deployment strategy—developing a plan for the acquisition of nextgeneration EDS systems, the redeployment of existing EDS assets, 

and investment in life-cycle extension programs; 

• EDS Life-Cycle Management Plan—structuring guidelines for EDS 

research and development investment, procurement specifications 

for next-generation EDS systems, and the redeployment of existing 

EDS assets and investment in life-cycle extension programs that 

minimize the cost of ownership of the EDS systems; and 

• Stakeholder collaboration plan—working with airport operators 

and other key stakeholders to develop airport-specific screening 

solutions, refine the nationwide EDS deployment strategy, and 

investigate alternative funding programs that may allow for 

innovative as well as non-federal sources of funding or financing, 

including formulas for sharing costs among different government 

entities and the private sector. 

TSA said it is continuing its efforts in these areas as it works toward 

completing a comprehensive strategic plan for its checked baggage 

screening program. TSA expects to complete the strategic plan in early fall

2006. 

While TSA has begun to conduct a systematic prospective analysis to 

determine at which airports it could achieve long-term savings and 

enhanced efficiencies and security by installing in-line systems or by 

 26TSA has determined that the details of its analysis of the optimal checked baggage 

screening solutions are sensitive security information. 

Page 16 GAO-06-875T 
making greater use of stand-alone EDS machines in lieu of ETD machines, 

resources have not been made available on a large-scale basis to fund 

these systems. In-line baggage screening systems are capital-intensive 

because they often require significant airport modifications, including 

terminal reconfigurations, new conveyor belt systems, and electrical 

upgrades. According to TSA, lessons learned from the first airports where 

in-line systems were built identified that facilities and infrastructure 

modifications accounted for up to 50 percent of the total cost of in-line 

screening systems, and modifications and upgrades to the baggage 

handing system typically accounted for another 25 percent of the total 

cost. In February 2006, TSA estimated that the total cost of installing and 

operating the optimal checked baggage screening systems, including inline EDS machines, at the 250 airports is approximately $22.4 billion over 

20 years, of which about $6 billion is for installation, life-cycle 

replacement, existing committed funding, and equipment maintenance 

costs.27 According to TSA officials, the estimated costs to install in-line 

baggage screening systems would vary greatly from airport to airport 

depending on the size of the airport and the extent of airport modifications 

that would be required to install the system.28 In March 2005 we reported 

that while we did not independently verify the estimates, officials from the 

Airports Council International-North America and American Association 

of Airport Executives estimated that project costs for in-line systems could 

range from about $2 million for a category III airport to $250 million for a 

category X airport.29

TSA’s February 2006 strategic planning framework identified that because 

many of the EDS and ETD machines were deployed in 2002 and 2003 to 

comply with ATSA and subsequent deadlines for achieving the 100 percent 

 27Operating costs include costs related to staffing, training, and research and development. 

28According to TSA, a fully automated in-line screening system is not appropriate for every

airport, even when security and operational benefits are considered in the analysis. 

Therefore, for many smaller airports or at smaller terminals or airline operational areas at 

larger airports, the identification of other alternative in-line solutions, such as partially 

automated ones, will accomplish the same goal of moving checked baggage screening out 

of terminal lobbies. In February 2006, TSA reported that most of these solutions also offer

significant TSO savings over comparable airport lobby systems.

29Joint Statement of David Z. Plavin, President, Airports Council International-North 

America (ACI-NA) and Todd Hauptli, Senior Executive Vice President, American 

Association of Airport Executives (AAAE) before the House Aviation Subcommittee 

Hearing on Passenger and Baggage Screening Problems, February 12, 2004. GAO did not 

independently verify cost figures provided in this testimony. 

Page 17 GAO-06-875T 
checked baggage screening mandate, a large share of the EDS machines 

will incur life-cycle replacement obligations during the 2013 to 2014 time 

period. Although TSA has not completed its efforts to develop a life-cycle 

cost model,30 TSA’s February 2006 strategic planning framework identified

that a substantial funding requirement for EDS equipment life-cycle 

replacement will compete with funding requirements for new in-line 

systems in approximately 8 to 9 years.31 Further, in June 2006, as discussed 

in the framework, TSA officials reported that if the top 25 airports do not 

receive in-line checked baggage screening systems, they will require 

additional screening equipment to be placed in airport lobbies and 

additional TSO staffing in order to remain in compliance with the mandate

for screening all checked baggage using explosive detection systems. 

TSA Is Collaborating with 

Key Stakeholders to 

Identify Funding and 

Financing Strategies for 

Installing Optimal Baggage 

Screening Systems 

In March 2005, we reported that TSA and airport operators were relying on

several sources of funding to construct in-line checked baggage screening 

systems. One source of funding airport operators used was FAA’s Airport 

Improvement Program, which traditionally funds grants to maintain safe 

and efficient airports. In fiscal years 2002 and 2003, 28 of the 53 airport 

officials we interviewed reported that their airports either had constructed 

or were planning to construct in-line systems relying on the Airport 

Improvement Program as their sole source of federal funding. With Airport 

Improvement Program funds no longer available after fiscal year 2003 for 

this purpose, airports turned to other sources of federal funding to 

construct in-line systems.32 The fiscal year 2003 Consolidated 

Appropriations Resolution approved the use of LOIs as a vehicle to 

leverage federal government and industry funding to support facility 

modification costs for installing in-line EDS baggage screening systems.33

Between June 2003 and February 2004, TSA issued eight LOIs to reimburse 

nine airports for the installation of in-line EDS baggage screening systems 

 30Life-cycle costs provide an estimate of how long the machines will be in operation and the 

estimated maintenance costs over this period. 

31According to TSA, EDS machines are estimated to have a useful life of 7 years, extended

to 11 years with refurbishment. 

32 The Consolidated Appropriations Act, 2004, prohibited the use of Airport Improvement

Program funds for activities related to the installation of in-line explosive detection 

systems. See Pub. L. No. 108-199, 118 Stat. 3, 283. The Consolidated Appropriations Act, 

2005, and the Department of Transportation Appropriations Act, 2006, continued this 

prohibition. See Pub. L. No. 108-447, 118 Stat. 2809, 3203 (2004); Pub. L. No. 109-115, 119 

Stat. 2396, 2400-01 (2005). 

33Consolidated Appropriations Resolution, 2003, Pub. L. No. 108-7, § 367, 117 Stat. 423-24. 

Page 18 GAO-06-875T 
for a total cost of $957.1 million to the federal government over 4 years. 

That cost represents 75 percent of the facility modification costs, with the 

airport funding the remaining costs.34 TSA also uses other transaction 

agreements as an administrative vehicle to directly fund, with no long-term 

commitments, airport operators for smaller in-line airport modification 

projects.35Under these agreements, as implemented by TSA, the airport 

operator also provides a portion of the funding required for the 

modification. As of June 2006, TSA reported that about $140 million had 

been obligated for other transaction agreements for in-line EDS systems. 

To fund the procurement and installation of explosive detection systems 

in-line, TSA also uses annual appropriations and the $250 million 

mandatory appropriation of the Aviation Security Capital Fund.

36 For 

example, in fiscal years 2005 and 2006, TSA received appropriations of 

$175 million and $180 million, respectively, for the procurement of 

explosive detection systems and received $45 million each year for the 

installation of explosive detection systems. For fiscal year 2007, DHS 

requested $91 million for the procurement of explosive detection systems 

and $94 million for the installation of such systems. Of the $250 million 

available through the Aviation Security Capital Fund, $125 million is 

 34Under an LOI, the airport operator is responsible for providing the total funding needed to

complete the project with an expectation that the federal government will reimburse the

airport for a set percentage of the costs over an agreed upon period of time, contingent

upon the availability of federal funds. Under all LOIs issued by TSA, the federal government

bears 75 percent of the cost, while the airport operators bear 25 percent of the costs. 

Although the Vision 100—Century of Aviation Reauthorization Act (Vision 100), Pub. L. No.

108-176, § 605, 117 Stat. 2490, 2566-68 (2003) revised this cost share to reflect a 90 percent – 

10 percent difference, subsequent appropriations acts have maintained the original 75 - 

25 cost share for medium and large hub airports. See 49 U.S.C. § 44923 but see, e.g., Pub. L.

No. 109-90, 119 Stat. 2070 (2005). 

35Other transaction agreements are administrative vehicles used by TSA to directly fund 

airport operators for smaller airport modification projects without undertaking a long-term 

commitment. These transactions take many forms and are generally not required to comply 

with federal laws and regulations that apply to contracts, grants, or cooperative 

agreements; and enable the federal government and others entering into these agreements 

to freely negotiate provisions that are mutually agreeable. 

36Vision 100 established the Aviation Security Capital Fund, which authorized a mandatory

appropriation of $250 million for each of fiscal years 2004 through 2007 in support of

airport improvement projects related to the installation of explosive detection systems. See 

49 U.S.C. § 44923. In the fiscal year 2004 DHS Appropriations Act, however, Congress

appropriated $250 million for the physical modification of airports to install checked 

baggage explosive detection systems but did so separate from the capital fund. A provision

of that act precluded the use of funds to establish the capital fund in fiscal year 2004. 

Congress must reauthorize the capital fund for it to continue beyond fiscal year 2007. 

Page 19 GAO-06-875T 
designated as priority funding for LOIs. The remaining $125 million is to be 

allocated in accordance with a formula based upon the size of the airport 

and risks to aviation security.37 Congress also authorized an additional 

appropriation of $400 million per year through fiscal year 2007 for airport 

security improvement projects that relate to the use of in-line EDS 

systems. However, appropriations have not been made under this 

authorization.38

In July 2004, as part of this subcommittee’s hearing on TSA’s progress in 

deploying in-line systems, TSA reported that there were nine in-line 

systems in place and an additional nine were due to be completed by 2006.

In March 2005, we reported that 12 airports had operational in-line systems 

airportwide or at a particular terminal or terminals. As of June 2006, 

25 airports had operational in-line EDS systems and an additional 

24 airports had in-line systems under development. Additionally, TSA 

reported that it has received requests from an additional 50 airports either 

seeking funding to construct in-line EDS systems or reimbursement for 

already completed in-line systems. Table 4 provides information on the 

status of in-line system deployment as of February 2006. 

Table 4: Airports with In-line Explosives Detection Systems That Are Operational or 

Under Construction by Airport Category as of June 2006 

Airport category 

Status of in-line EDS system X I II III IV

Operational 8 11 4 2 0

Under Construction 12 12 0 0 0

Source: GAO analysis of TSA data. 

In a May 2006 meeting of the Aviation Security Advisory Committee, TSA 

reported that under current investment levels, installation of optimal 

checked baggage screening systems would not be completed until 

 37 The pending fiscal year DHS Appropriations Act, as passed by the House of

Representatives, proposes to eliminate the funding formula as applied to the Aviation

Security Capital Fund and other appropriations authorized under 49 U.S.C. § 44923. See 

H.R. 5441, 109th Cong. (2006). 

38These additional authorized appropriations are to follow the same 50 percent split as

mandated under the Aviation Security Capital Fund. See 49 U.S.C. § 44923(i). 

Page 20 GAO-06-875T 
approximately 2024.39 TSA further reported that unless investment is 

accelerated, substantial investment will be needed to replace EDS and 

ETD machines at the end of their life cycles and to refurbish suboptimal 

systems. TSA is currently collaborating with airport operators, airlines, 

and other key stakeholders to develop a cost-sharing study that identifies 

funding and cost-sharing strategies for the installation of in-line baggage 

screening systems. TSA plans to use the results of this study to finalize its 

checked baggage screening program strategic plan, which TSA expects to

complete by early fall 2006.40 In its May 2006 report to the Aviation Security

Advisory Committee, TSA outlined financing options including leasing 

equipment, sharing savings from in-line systems with airports, and 

enhancing eligibility for the Passenger Facility Charge,41 LOIs, and tax 

credit bonds.42 In this meeting, TSA reported that tax credit bonds had the 

most potential support among stakeholders. 

As TSA moves forward with planning for the deployment of checked 

baggage screening systems and identifying funding and financing options, 

it is also important for TSA to engage in planning to focus its research and 

development efforts. To enhance checked baggage screening, TSA is 

developing and testing next-generation EDS machines. According to TSA,

manufacturers have only marginally improved false alarm rates and 

throughput capabilities of the equipment since the large-scale deployment 

of EDS machines in 2002 and 2003. The maximum number of bags an EDS 

machine can screen per hour is 500, which can be achieved only when the 

machines are integrated in-line with the baggage conveyor system. New 

EDS equipment was certified in 2005, including a smaller EDS machine 

 39The Aviation Security Advisory Committee’s mission is to examine areas of civil aviation 

security as tasked by TSA with the aim of developing recommendations for the 

improvement of civil aviation security methods, equipment, and procedures. Its

membership includes government officials and private sector organizations representing

key constituencies affected by aviation security requirements. 

40Section 4019(d) of the Intelligence Reform and Terrorism Prevention Act of 2004 requires 

the Secretary of Homeland Security to complete a cost-sharing study in collaboration with 

industry stakeholders to review the benefits and cost of in-line checked baggage screening 

systems, innovative financing approaches, formulas for cost sharing among different

government entities and the private sector, and potential cost-saving approaches. 

41The Passenger Facility Charge (PFC) Program allows the collection of PFC fees up to 

$4.50 for every enplaned passenger at commercial airports controlled by public agencies. 

Airports use these fees to fund FAA-approved projects that enhance safety, security, or

capacity; reduce noise; or increase air carrier competition. 

42 Tax credit bonds are bonds where bondholders receive credit against their federal 

income tax liabilities instead of cash interest. 

Page 21 GAO-06-875T 
designed to replace ETD machines used for primary screening and an

upgraded large EDS machine. In September 2005, TSA entered into a 

$24.8 million contract to purchase 72 smaller EDS machines to be installed 

at 24 airports. The President’s fiscal year 2007 budget request for TSA 

includes funding to support research and development for in-line EDS 

machines that can operate at up to 900 bags per hour and employ new 

threat detection concepts. In its February 2006 strategic framework for 

checked baggage screening, TSA identified the development of highthroughput in-line EDS machines and lowering of EDS false alarm rates as 

key areas for improving investment management of next-generation 

technologies. TSA reported that these performance gains would be 

feasible and available in the near term. TSA also reported that given that 

the planning, design, and construction cycle for an in-line system can be 

2 to 3 years, and these high-throughput and lower false alarm rate 

technologies are anticipated to be deployable by about 2008, the agency is

recommending that all in-line planning and design efforts consider these 

new technologies. 

We reported in September 2004 that the Department of Homeland Security 

(DHS) and TSA have made some progress in managing their transportation 

security research and development programs according to applicable laws 

and R&D best practices.43 However, we found that their efforts were 

incomplete in several areas, including preparing strategic plans for R&D 

efforts that contain measurable objectives, preparing and using risk 

assessments to select and prioritize R&D projects, and coordinating with 

stakeholders—a condition that increases the risk that their R&D resources 

will not be effectively leveraged. We also found that TSA and DHS delayed 

several key R&D projects and lacked both estimated deployment dates for

the vast majority of their R&D projects and adequate databases to 

effectively manage their R&D portfolios. We recommended that DHS and 

TSA (1) conduct some basic research in the transportation security area;

(2) complete their strategic planning and risk assessment efforts; 

(3) develop a management information system that will provide accurate,

complete, current, and readily accessible project information for 

monitoring and managing their R&D portfolios; and (4) develop a process 

with the Department of Transportation to coordinate transportation 

security R&D efforts and share this information with transportation 

stakeholders. In June 2006, DHS reported several actions that it had taken 

to address these recommendations, including coordinating with other 

 43The DHS Science and Technology Directorate took over R&D from TSA in October 2005. 

Page 22 GAO-06-875T 
federal agencies to leverage their basic research, issuing a Science and 

Technology Directorate Strategic Plan, implementing a program and 

project management system to monitor program and project funding and 

milestones, and establishing a memorandum of agreement that resulted in 

the formation of a Mass Transit Technology Working Group to coordinate 

efforts across agencies and to optimize resources. DHS also reported that

basic research has been limited because the majority of R&D funds have 

been appropriated for countermeasures for specific threat areas. We will 

examine these efforts to implement our recommendations as part of our 

ongoing review of DHS’s and TSA’s airport checkpoint R&D program. 

TSA has made progress in installing EDS and ETD systems at the nation’s 

airports—mainly as part of interim lobby screening solutions—to provide 

the capability to screen all checked baggage for explosives as mandated by

Congress. With the objective of initially fielding this equipment largely 

accomplished, TSA has shifted its focus from equipping airports with 

interim screening solutions to systematically planning for the more 

optimal deployment of checked baggage screening systems. 

Concluding 

Observations 

TSA’s February 2006 strategic planning framework for the checked 

baggage screening program is a positive step forward in systematically 

planning for the more optimal deployment of checked baggage screening 

systems. The completion of a strategic plan for checked baggage screening 

by early fall 2006 should help TSA more fully determine whether expected 

reduced staffing costs, higher baggage throughput, and increased safety 

and security will in fact justify the significant up-front investment required 

to install in-line baggage screening systems. TSA’s retrospective analysis 

on nine airports installing in-line baggage screening systems with LOI 

funds, while limited, estimated that cost savings could be achieved 

through reduced staffing requirements for TSOs and increased baggage 

throughput. Specifically, the analysis identified that using in-line systems 

instead of stand-alone systems at these nine airports could save the federal 

government about $1.3 billion over 7 years and that TSA’s initial 

investment would be recovered in a little over 1 year. TSA also recently 

estimated that a saving of approximately $4.7 billion could be realized over 

a period of 20 years by installing optimal checked baggage screening 

systems at the 250 airports with the highest checked baggage volumes. 

However, TSA’s strategic planning framework identified that many of the 

initial in-line systems have produced a level of savings insufficient to offset 

up-front capital costs of acquiring and installing the systems. Nevertheless, 

TSA reported that recent improvements in the design of the systems and 

Page 23 GAO-06-875T 
EDS screening technology now offer the opportunity for higher 

performance and lower-cost screening systems. 

In-line EDS baggage screening systems have efficiency, safety, and 

security benefits that have been reported on extensively by Congress, 

GAO, TSA, and aviation industry representatives. As part of its strategic 

planning efforts, TSA has identified the top 25 airports that should first 

receive federal funding for projects related to the installation of explosive 

detection systems and also identified the ideal mix of higher-performance 

and lower-cost alternative screening solutions for the 250 airports with the 

highest checked baggage volumes. With this initial planning now 

completed, a critical question that remains is how to fund and finance 

these screening systems and who should pay for them. TSA is currently 

working with airport and air carrier stakeholders to identify funding and 

financing options, an effort that is due to be completed by early fall 2006. 

As TSA works toward identifying funding and financing options, it will 

also be important for the agency to sustain its R&D efforts and further 

strengthen its R&D management and planning efforts. Researching and 

developing technologies, such as higher-throughput EDS machines with 

lower false alarm rates, should help TSA to improve the security and 

efficiency of checked baggage screening. 

Mr. Chairman, this concludes my statement. I would be pleased to answer 

any questions that you or other members of the subcommittee have. 

For further information on this testimony, please contact Cathleen A. 

Berrick at (202) 512-3404 or berrickc@gao.gov. Contact points for our 

Offices of Congressional Relations and Public Affairs may be found on the 

last page of this statement. 

Contact Information 

In addition to the contact named above, Kevin Copping, Katherine Davis, 

Michele Fejfar, Thomas Lombardi, Allison Sands, and Maria Strudwick 

made key contributions to this testimony. 

Page 24 GAO-06-875T 
Page 25 GAO-06-875T 

Related GAO Products 

Aviation Security: Enhancements Made in Passenger and Checked 

Baggage Screening, but Challenges Remain. GAO-06-371T. Washington,

D.C.: April 4, 2006. 

Aviation Security: Progress Made to Set Up Program Using PrivateSector Airport Screeners, but More Work Remains. GAO-06-166. 

Washington, D.C.: March 31, 2006. 

Aviation Security: TSA Management of Checked Baggage Screening 

Procedures Could Be Improved. GAO-06-291SU. Washington, D.C.: 

February 28, 2006. 

Transportation Security Administration: More Clarity on the Authority 

of Federal Security Directors Is Needed. GAO-05-935. Washington, D.C.: 

September 23, 2005. 

Aviation Security: Better Planning Needed to Optimize Deployment of 

Checked Baggage Screening Systems. GAO-05-896T. Washington, D.C.: 

July 13, 2005.

Aviation Security: Screener Training and Performance Measurement 

Strengthened, but More Work Remains. GAO-05-457. Washington, D.C.: 

May 2, 2005.

Aviation Security: Systematic Planning Needed to Optimize the 

Deployment of Checked Baggage Screening Systems. GAO-05-365. 

Washington, D.C.: March 15, 2005. 

Transportation Security: Systematic Planning Needed to Optimize 

Resources. GAO-05-357T. Washington, D.C.: February 15, 2005. 

Aviation Security: Preliminary Observations on TSA’s Progress to Allow 

Airports to Use Private Passenger and Baggage Screening Services. 

GAO-05-126. Washington, D.C.: November 19, 2004. 

Aviation Security: Private Screening Contractors Have Little Flexibility 

to Implement Innovative Approaches. GAO-04-505T. Washington, D.C.: 

April 22, 2004. 

Aviation Security: Improvement Still Needed in Federal Aviation 

Security Efforts. GAO-04-592T. Washington, D.C.: March 30, 2004. 
Aviation Security: Challenges Exist in Stabilizing and Enhancing 

Passenger and Baggage Screening Operations. GAO-04-440T. Washington,

D.C.: February 12, 2004. 

Aviation Security: Efforts to Measure Effectiveness and Strengthen 

Security Programs. GAO-04-285T. Washington, D.C.: November 20, 2003. 

Aviation Security: Efforts to Measure Effectiveness and Address 

Challenges. GAO-04-232T. Washington, D.C.: November 5, 2003. 

(440526) Page 26 GAO-06-875T 
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