GAO-04-499R Aviation Security 

United States General Accounting Office

Washington, DC 20548 

March 5, 2004 

The Honorable Tom Ridge 

Secretary, Department of Homeland Security 

Subject: Aviation Security: Factors Could Limit the Effectiveness of the 

Transportation Security Administration’s Efforts to Secure Aerial Advertising 

Operations 

Dear Mr. Secretary: 

After the terrorist attacks of September 11, 2001, the Federal Aviation Administration 

(FAA) issued flight restrictions to prevent flights over certain areas, to include 

stadiums, in response to increased concerns about the threat posed by terrorists 

using aircraft as a weapon. Larger stadiums, some of which may house more than 

100,000 fans for certain events, may provide an attractive target for such a terrorist 

attack. Beginning in December 2001, FAA’s Air Traffic Division Director of Air Traffic 

Services, and later the Transportation Security Administration (TSA), implemented 

processes to allow certain pilots and aircraft to operate over these events by waiving 

flight restrictions. However, in February 2003, Congress passed legislation that for 1 

year prevented aerial advertising pilots1

 from flying near stadium airspace during 

certain sporting events by suspending the waiver process. In January 2004, Congress 

passed legislation continuing this restriction indefinitely.2

In the event that the restriction on waivers for aerial advertising near stadiums is 

repealed, the House Appropriations Committee, Subcommittee on Homeland 

Security, asked that we (1) describe the results of FAA and TSA threat assessments 

conducted relevant to aerial advertising operations and (2) identify FAA’s and TSA’s 

processes for mitigating the identified threat, determine whether established 

processes were followed, and identify factors that may limit their effectiveness. Due 

to TSA’s concern that the public release of our detailed findings could compromise 

aviation security, our report detailing the results of our review is restricted. This 

letter is intended to summarize our overall findings and confirm your agreement to 

take action to address vulnerabilities and inefficiencies in the background check 

process for aerial advertisers in the event that the waiver restriction is repealed. 

Such actions could also improve the quality of background checks for all general 

aviation pilots seeking waivers of security-related flight restrictions. 

 

1

 Aerial advertising aircraft are small aircraft that tow advertising banners. 

2

 Pub. L. No. 108-199, Section 521, Consolidated Appropriations Act, 2004. 
Page 2 GAO-04-499R Aviation Security 

To satisfy our objectives, we assessed FAA and TSA regulations, policies, procedures, 

and documents related to issuing waivers to flight restrictions and associated threat 

assessments. We also reviewed a sample of waivers approved by TSA and issued by 

FAA to allow aerial advertising pilots to fly over stadiums from September 2002 

through February 2003, and interviewed responsible FAA and TSA officials. We 

conducted our work between November 2003 and February 2004 in accordance with 

generally accepted government auditing standards. 

Results in Brief 

While TSA does not believe aerial advertising aircraft pose a significant threat, TSA‘s 

summary assessment of general aviation3

 concluded that a variety of factors made 

general aviation vulnerable to terrorist attacks. TSA identified that these factors, as 

well as the ability of terrorist organizations such as al-Qaeda to adopt new and 

creative methods of attack, highlight the need for security of all operations using 

general aviation aircraft and airports, including aerial advertisers. To mitigate this 

threat, TSA plans to coordinate with an industry-led initiative to study security 

vulnerabilities associated with general aviation aircraft and also plans to issue a set of 

“best practices,” or recommended guidelines to improve security at general aviation 

airports, as well as a self-assessment guide for general aviation airport managers to 

use. 

After assuming responsibility for processing waivers for aerial advertisers to fly over 

restricted stadium airspace from FAA, TSA began to strengthen and implement 

additional processes to enhance security, including strengthening background checks 

on aerial advertisers. Although we generally found documentation identifying that 

background checks were conducted, we identified certain factors that could limit the 

effectiveness of these checks. In addition, inconsistency in the manner in which 

information was collected to identify pilots and match them to the results of the 

checks conducted made it difficult to verify that the background checks were 

conducted as required. Further, FAA and TSA reported that they used additional 

processes to reduce the threat of aerial advertising operations. However, we found 

that these processes were not formalized in agency policies or procedures, and 

thereby, may not have been consistently applied. 

To address the factors we identified that could limit TSA’s effectiveness to secure 

aerial advertising operations, we recommended that, in the event that waiver 

restrictions are repealed, the Administrator of TSA should determine whether more 

comprehensive background checks are warranted to further reduce the threat of 

aerial advertising operations; ensure that documents supporting waivers granted for 

temporary flight restrictions are systematically and fully maintained; and disseminate 

policies defining the process and procedures for issuing waivers, conducting 

background checks, and defining the circumstances under which TSA will take 

additional steps to ensure verification that pilots flying over restricted stadium 

airspace have been properly cleared. In commenting on this report, FAA and TSA 

officials generally agreed with the information provided and our recommendations. 

Officials also provided technical clarifications that we incorporated as appropriate. 

 

3

 General aviation consists of all civil aircraft, excluding commercial and military, as well as general 

aviation airports where these aircraft are based. 
Page 3 GAO-04-499R Aviation Security 

Background 

Following the September 11th terrorist attacks, FAA issued several temporary flight 

restrictions to prevent flights over certain areas. After its creation and assumption of 

aviation security responsibilities, TSA began determining when and where securityrelated temporary flight restrictions should be issued.4

 Although TSA determines the 

aviation security risks, FAA retains responsibility—due to its oversight of U.S. 

airspace—for signing and issuing airspace restrictions and associated waivers. FAA 

formally informs the aviation industry of such restrictions through numbered notices 

to airmen (NOTAM). One restriction prohibited flights over public assemblies and 

large stadiums to enhance security over events being held at these sites.5

 Beginning 

in December 2001, FAA’s Air Traffic Office began to allow certain pilots and aircraft 

to operate over these events by waiving flight restrictions. These waiver processes 

allowed pilots, such as those flying aerial advertising aircraft, to obtain a waiver from 

the restriction and fly in restricted airspace. In the spring of 2002, FAA began to 

conduct background checks on pilots applying for waivers from flight restrictions. 

In September 2002, TSA recommended that FAA amend previous NOTAMs to clarify 

the events over which flights should be restricted. Rather than all public assemblies, 

flight restrictions were narrowed to include only flights over National Football 

League, Major League Baseball, National Collegiate Athletic Association Division 1 

football, and major motor speedway events at stadiums with 30,000 seats or more. 

The restrictions extended 3 miles out from the center of the stadium and 3,000 feet 

above ground level. Based on experiences and knowledge gained in working with 

FAA to address security issues following the September 11 attacks, TSA developed a 

process for conducting background checks on pilots requesting waivers to fly over 

these events and began processing waiver applications.6

 FAA, as manager of the U.S. 

airspace, continued to sign and issue the waivers. 

TSA’s processes for approving waivers were in place until February 2003, when 

Congress directed that restrictions be placed on the type of pilots and aircraft 

allowed to obtain a waiver to fly over restricted stadium airspace.7 These new 

restrictions allowed only aircraft having broadcast, safety and security, or other 

operational purposes to fly in the airspace. For example, law enforcement, medical, 

and Department of Defense aircraft were exempted from the restrictions as well as 

aircraft required to fly through the restricted airspace to arrive or depart from a 

nearby airport. This legislation barred all other operations, including aerial 

advertisers, from obtaining waivers through February 20, 2004, unless extended by 

Congress. In January 2004, Congress passed legislation continuing this restriction 

indefinitely. Figure 1 shows a time line of events leading to the suspension of aerial 

advertising waivers. 

 

4

 The Aviation and Transportation Security Act (ATSA), Pub. L. No. 107-71, § 101(g), 115 Stat. 597, 603 

(2001), transferred much of the responsibility for civil aviation security from FAA to TSA. 3

 NOTAM 1/3353, issued December 19, 2001. 

6

 TSA conducts such background checks when considering waiver requests for all security-related 

temporary flight restrictions, including checks for pilots, crew members, and passengers. 

7

 Consolidated Appropriations Resolution, 2003, Pub. L. No. 108-7, § 352, 117 Stat. 11, 420-21 

(implemented by FAA in NOTAM 3/1840, issued Mar. 6, 2003). 
Page 4 GAO-04-499R Aviation Security 

Figure 1: Time line of Events Leading to the Suspension of Aerial Advertising Waivers 

TSA’s Threat Assessments Found General Aviation to Be Vulnerable 

While the agency does not believe aerial advertising aircraft pose a significant threat 

and are not likely to be used by terrorists, TSA concluded that a variety of factors 

made general aviation, including aerial advertising operations, vulnerable to terrorist 

attack. TSA identified that these factors, as well as the ability of terrorist 

organizations such as al-Qaeda to adopt new and creative methods of attack, 

highlight the need for security of all operations using general aviation aircraft and 

airports, including aerial advertisers. 

TSA plans to coordinate with an industry-led initiative to study security 

vulnerabilities associated with a spectrum of general aviation aircraft (from smallest 

to largest and heaviest), operating under a variety of scenarios, and with a variety of 

payloads. Through this coordination, TSA plans to provide guidance to industry 

participants in an effort to ensure the results provide information that will benefit 

both the government and industry. TSA also plans to issue a set of “best practices,” 

or recommended guidelines to improve security at general aviation airports, and a 

self-assessment guide for general aviation airport managers to use by March 2004. 
Page 5 GAO-04-499R Aviation Security 

TSA Enhanced Security Processes for Aerial Advertising Operations, but 

Limitations Exist 

 

When TSA assumed responsibility for managing the waiver process in September 

2002, the agency began taking steps to conduct more extensive background checks 

for aerial advertising pilots than those previously conducted by FAA. According to 

FAA and TSA, FAA began issuing waivers to aerial advertising pilots in December 

2001 but did not begin conducting background checks on pilots until sometime in 

March or April 2002. When TSA assumed responsibility for managing the waiver 

process, the agency instituted additional processes for conducting background 

checks, which included more extensive checks of a pilot’s criminal history and 

associated links to terrorism. TSA said the agency used these processes to determine 

whether to grant waivers for any security-related temporary flight restriction beyond 

only waivers for aerial advertising pilots. Despite these efforts, however, we found 

weaknesses in the process used to conduct background checks that could impact the 

security of aerial advertising operations. 

In addition to strengthening background checks for aerial advertising pilots granted 

waivers to fly over stadiums, TSA took steps to document that these background 

checks were completed. For the period between December 2001 and September 

2002, when FAA was responsible for managing the waiver process, officials did not 

track waivers granted or maintain file documentation of background check results. 

As a result, we could not verify that FAA conducted all background checks as 

reported. After TSA assumed responsibility for processing waiver applications, the 

agency established a tracking system to document the results of background checks. 

To determine whether TSA followed their process for approving waivers and 

conducting background checks for aerial advertisers requesting waivers, we reviewed 

a random sample of 100 waivers (of the 900 total waivers contained in TSA’s internal 

tracking system as having been processed for aerial advertising pilots from 

September 2002 until February 2003) and determined whether documentation existed 

that showed that the additional checks instituted by TSA were conducted. We found 

that although checks were generally documented, inconsistency in the manner in 

which information was collected to identify pilots and match them to the results of 

the checks conducted made it difficult to verify that the background checks were 

conducted as required. For example, pilots applying for waivers were organized 

alphabetically in the documentation of one check, whereas results of the terrorist 

threat analysis were organized by a pilot’s social security number. In addition, TSA 

tracked the waivers by pilot certificate number in some cases, further complicating 

the process of matching the results of one check and terrorist threat analysis to the 

waivers applied for and granted. 

Federal regulations require that agency record-keeping procedures provide 

documentation to facilitate review by Congress and other authorized agencies of 

government.8

 Further, our standards for internal control in the federal government9

require that all transactions be clearly documented in a manner that is complete, 

 

8

 36 C.F.R. § 1222.38. 

9

 31 U.S.C. 3512(c). 
Page 6 GAO-04-499R Aviation Security 

accurate, and useful to managers and others involved in evaluating operations. In the 

absence of a more effective system for documenting and maintaining records of the 

results of background checks and other analyses, TSA cannot, among other things, 

hold responsible officials accountable for completing required steps in the 

background check process. 

In addition to the background check process used to check pilots, FAA and TSA 

stated that they used additional processes to reduce the threat of aerial advertising 

operations. For example, both TSA and FAA told us that they coordinated with local 

law enforcement officials and FAA air traffic control towers to inspect aerial 

advertising pilots and their aircraft and to verify that they had a valid waiver. 

However, we found that these processes were not formalized in agency policies or 

procedures, and thereby, may not have been consistently followed related to aerial 

advertising operations. 

- - - - - - 

In addition to the Department of Homeland Security, we are sending copies of this 

report to the House Appropriations Committee, Subcommittee on Homeland 

Security. We will also make copies available to others upon request. In addition, the 

report will be available at no charge on GAO’s Web site at http://www.gao.gov. 

If you or your staff have any questions about this report, please call me at (202) 512-

3404 or Chris Keisling, Assistant Director, at (404) 679-1917.

Sincerely yours, 

Cathleen A. Berrick 

Director, Homeland Security and Justice Issues

(440298)