Drug Control: Air Bridge Denial Program in Colombia Has Implemented New Safeguards, but Its Effect on Drug Trafficking Is Not Clear
Published: 2005-09-06T00:00:00

Fast Facts:

Highlights:
section_title: Why GAO Did This Study
paragraphs: In the 1990s, the United States operated a program in Colombia and Peru called Air Bridge Denial (ABD). The ABD program targeted drug traffickers that transport illicit drugs through the air by forcing down suspicious aircraft, using lethal force if necessary. The program was suspended in April 2001 when a legitimate civilian aircraft was shot down in Peru and two U.S. citizens were killed. The program was restarted in Colombia in August 2003 after additional safeguards were established. To date, the United States has provided about $68 million in support and plans to provide about $26 million in fiscal year 2006. We examined whether the ABD program's new safeguards were being implemented and its progress in attaining U.S. and Colombian objectives.
section_title: What GAO Found
paragraphs: The United States and Colombia developed additional safeguards for the renewed ABD program to avoid the problems that led to the accidental shoot down in Peru. The safety measures aim to reinforce and clarify procedures, bolster safety monitoring, enhance language skills of ABD personnel, and improve communication channels. We found the safeguards were being implemented by the Colombians and U.S. safety monitors. In addition, the program managers perform periodic reviews and evaluations, including an annual recertification of the program, and have made efforts to improve civilian pilots' awareness of the ABD program's procedures. Our analysis of available data indicates that the ABD program's results are mixed, but the program's progress cannot be readily assessed because performance measures with benchmarks and timeframes do not exist. The stated objective for the program--for the Colombian National Police to take control of suspicious aircraft--seldom happens. During October 2003 through July 2005, the Colombian Air Force located only 48 aircraft out of about 390 suspicious tracks pursued; and the military or police took control of just 14 aircraft--four were already on the ground. Only one resulted in a drug seizure. However, many of the suspicious aircraft land in remote locations controlled by insurgent groups that require time to enter safely. Yet, the air force rarely involves the police besides calling them at the start of a mission and before firing at the suspicious aircraft. In addition, many of the suspicious tracks are near border areas with Brazil and Venezuela, which is too far from an ABD air base for aircraft to intercept without refueling. Nevertheless, the number of suspicious tracks has apparently declined from 49 to 30 per month, but the track counts may not be consistent over time because they are based on subjective criteria, such as whether an aircraft has inexplicably deviated from its planned flight path. According to U.S. and Colombian officials, the reduction in suspicious tracks indicates that Colombia is deterring traffickers and regaining control of its airspace.

section_title: Letter
paragraphs: Drug traffickers in South America often move illegal drugs by aircraft in  and out of Colombia. This is referred to as the “air bridge.” To reduce this  drug trafficking, the United States began operating a program in the 1990s  called Air Bridge Denial (ABD) in Colombia and Peru. The ABD program  identified aircraft suspected of drug trafficking and forced them to land,  using lethal force if necessary. However, the program was suspended in  April 2001 after a legitimate civilian aircraft was shot down in Peru, killing  two U.S. citizens. In August 2003, Colombia and the United States resumed  ABD operations in Colombia after entering into a Letter of Agreement  outlining each country’s responsibilities and safety measures to address  concerns.
The ABD program’s stated goal is to help Colombia stop the trafficking of  illegal drugs—primarily cocaine—in its airspace by forcing suspicious  aircraft to land safely so that law enforcement authorities can take control  of the aircraft, arrest suspects, and seize drugs. Aircraft suspected of  involvement in drug trafficking are usually first identified by relocatable  over-the-horizon radar. Following this initial identification, a surveillance  aircraft containing tracking equipment is sent to visually identify the source  of the suspicious radar track, and, if it appears to be a drug trafficking  aircraft, an aircraft equipped with weapons is sent to intercept or force the  aircraft to land using the minimal force necessary. The Colombian Air  Force operates the ABD program and provides crews for both the U.S.- owned surveillance aircraft and Colombia’s interceptor aircraft. The  program is overseen by the Department of State’s (State) Bureau for  International Narcotics and Law Enforcement Affairs (INL), which has a  contract with a U.S. company, ARINC, to maintain the surveillance aircraft  and provide safety monitors and operational and training support. In  addition, the Department of Defense’s (Defense) Joint Interagency Task  Force-South (JIATF-South) provides radar intelligence to the Colombian  Air Force regarding suspicious tracks in and approaching Colombia,  collects and analyzes data on the performance of the program, and helps  ensure that the aircrews perform the required safety procedures.
At your request, we examined the status of the Colombian ABD program.  Specifically, we examined (1) the changes made to the ABD program to  address safety concerns raised after the Peru incident and whether these  new safeguards were being followed and (2) the program’s progress in  attaining U.S. and Colombian objectives.
To address these objectives, we reviewed ABD program and budget  documentation and met with cognizant U.S. officials at the Departments of  State and Defense in Washington, D.C. We traveled to Colombia and met  with officials from the Colombian government, Colombian Air Force, and  the U.S. Embassy, as well as ARINC personnel operating the ABD program.  We also visited an ABD air base in Apiay, Colombia, where many ABD  missions originate, and visited the Colombian Air Force’s ABD command  center in Bogotá. In addition, we met with JIATF-South personnel in Key  West, Florida, to discuss their role in the program. We performed our work  from January 2005 through August 2005 in accordance with generally  accepted government auditing standards.
subsections: section_title: Background
paragraphs: After the Peru accident, a joint investigation by the United States and Peru  reviewed the circumstances of the accident and made several conclusions.  The investigation team was comprised of U.S. representatives from the  Departments of State and Defense, as well as Peruvian officials from its  Ministries of Foreign Affairs and Defense.
According to U.S. officials, Colombian President Alvaro Uribe requested  the restart of the ABD program to help combat drug trafficking. After initial  discussions, the United States decided to assist Colombia in restarting a  revised ABD program that would be managed by the Colombian Air Force  and overseen by State/INL. In addition, U.S. officials said that Colombia  had existing infrastructure that facilitated the program’s restart, such as air  bases and a national air command center.
Prior to the restart of Colombia’s ABD program, a committee of  representatives from the Departments of State, Defense, and Justice, as  well as the Colombian government developed a Letter of Agreement  outlining the program’s goal, safety requirements, operational procedures,  and each country’s responsibilities. The Letter of Agreement, which was  signed in April 2003, states that the program’s goal is to increase the  Colombian government’s ability to stop aerial drug trafficking over  Colombia. Colombia is required to provide personnel and interceptor  aircraft, designate the areas where the program can operate in Colombia’s  airspace, and manage the daily operations. The United States is primarily  responsible for providing the program with surveillance aircraft, personnel,  training, and funds to maintain and operate the equipment, while ensuring  that the program is regularly reviewed. Finally, a U.S. Presidential  determination was necessary to restart the program, and is required  annually to allow U.S. employees and its agents to assist Colombia in the  use of force against civilian aircraft reasonably suspected to be primarily  engaged in illicit drug trafficking.
Since 2002, the United States has provided $68.4 million and surveillance  aircraft for the ABD program (see table 1) and plans to provide an  additional $25.9 million in fiscal year 2006. State/INL provided $57.2 million  to support ARINC operations, including the U.S. personnel involved in the  program and maintenance of the surveillance aircraft. State’s Narcotics  Affairs Section (NAS) in the U.S. Embassy in Bogotá provided $11.2 million  for training, aircraft operations, logistics support, and construction at ABD  air bases. At no cost to State, the department also transferred five U.S.- owned Cessna Citation surveillance aircraft used in the prior ABD  programs, which are equipped with tracking systems. Also, Defense gave  Colombia two additional surveillance aircraft, which have yet to be used  for surveillance. The fiscal year 2006 request for approximately $26 million  for the program is planned to continue existing operations and construct  additional infrastructure. U.S. and Colombian officials said they do not  intend for Colombia to fully finance the program in the near future.
section_title: United States and Colombia Implemented New Safety Requirements
paragraphs: In response to the findings of the Peru investigation and other  determinations, the United States and Colombia developed new safeguards  for the renewed ABD program which were implemented consistently in the  interdiction missions we observed. The program also undergoes multiple  evaluations to ensure that all elements of the Letter of Agreement are  followed.
subsections: section_title: New Safety Requirements Developed for ABD Program
paragraphs: The renewed ABD program has new safeguards in place, which were  prompted by the review of the Peru accident. The investigation of the Peru  incident found that crewmembers did not fully perform some procedures,  neglected the safety of the mission, had limited foreign language skills, and  were talking on a congested communication system. In response,  safeguards were developed to reinforce and clarify procedures, bolster  safety monitoring, enhance language skills of ABD personnel, and improve  communication channels. Another factor of the accident—the civilian  pilot’s unawareness of the ABD program’s procedures—was addressed by  teaching civilian pilots about the program.
In the Letter of Agreement for the renewed program, U.S. and Colombian  officials require ABD personnel to follow specific procedures summarized  in a safety checklist to ensure safe operations and clarify the roles of the  United States and Colombia (see app. I). According to the Peru  investigative report, the aircrews involved in the accident did not fully  execute the program’s procedures, particularly aircraft identification. Also,  the documentation of ABD procedures had become less specific over time.  The procedural checklist for the renewed program lists the specific steps  that must be taken to execute an ABD mission, including visually  identifying the suspicious aircraft; calling to the aircraft over the radio; and,  if necessary, requesting permission from the Commander of the Colombian  Air Force to fire at the aircraft. In particular, the list provides the exact  wording for crewmembers to use when confirming the completion of  checklist steps to avoid confusion among the participants. While at the  Colombian Air Force’s ABD command center in Bogotá, we observed ABD  personnel following the checklist during the start of an ABD mission.
While, at the time of the accident, the program did not have U.S. personnel  dedicated to monitoring safety, three U.S. personnel are now responsible  for safety and implementation of safeguards for each mission. The Peru  investigation concluded that the interceptor crewmembers were focused  on forcing aircraft to land and not on the overall safety of the mission.  Under the renewed program, the three U.S. safety monitors are located at  the Colombian Air Force’s command center in Bogotá; at JIATF-South in  Key West, Florida; and onboard the surveillance aircraft. The safety  monitor onboard the aircraft observes the completion of checklist  procedures and alerts the U.S. monitors on the ground when each  procedure is accomplished. If any of the three monitors objects to an  action taken during the mission, the monitor immediately stops the  mission. For example, if a monitor objects to the firing of warning shots  because he is not confident that the suspicious aircraft is involved in drug  trafficking, he will immediately pull all U.S. resources out of the mission,  including the surveillance aircraft and U.S. personnel. However, if the  problem is resolved, the mission can resume. As of June 2005, the U.S.  monitors had objected to actions in ten missions, two of which were due to  incorrect implementation of the checklist.
The Letter of Agreement with Colombia requires all U.S. safety monitors to  be fluent in Spanish and the Colombian crewmembers, besides the  weapons controllers, to be proficient in English because language barriers  among the aircrew members contributed to the Peru accident. The  aircrews involved in the Peru accident had flown on previous operational  missions together and had some foreign language skills; however, they  were not proficient enough to communicate clearly during the high stress  of an interception. For example, one of the crewmembers in the Peru  incident obtained the suspicious aircraft’s tail number so that ground  personnel could determine the owners of the aircraft. However, other  participants in the mission did not understand the message, and never  learned that the plane was a legitimate civilian aircraft. Under the renewed  program, the U.S. safety monitors are native Spanish speakers or were  formerly trained as linguists with the U.S. military. Annually, ARINC tests  the U.S. monitors fluency in Spanish and the NAS tests the Colombians’  proficiency in English.
Additionally, the renewed ABD program has incorporated improved  communications systems and procedures to ensure the communications  mishaps that contributed to the Peru accident do not reoccur. An ABD  interception requires the coordination of many individuals, including  ground personnel in the ABD command center in Bogotá and JIATF-South  in Key West, Florida, and aircrews in the surveillance and interceptor  aircraft. During the Peru accident, the aircrews were talking  simultaneously over the same radio channels and were not able to hear  each other clearly. For example, the crew of the suspicious aircraft called  the closest air control tower when they saw the interceptor aircraft  following them, but the control tower did not receive the call because it  was too far away. Although the ABD aircrews were monitoring the tower’s  radio frequency, they did not hear the call because other communication  was occurring at the same time. For the new program, a satellite radio  channel is dedicated to the U.S. monitors, and the Colombian  crewmembers communicate on various radio channels. A satellite phone is  also available if radio communication is impaired. The U.S. monitors must  suspend the mission if communication among them is lost, which has  happened three times.
Although not a finding of the Peru investigation, the Letter of Agreement  with Colombia recognizes that a community of civilian pilots unaware of  the ABD program can threaten the safety of the program’s operations.  Pilots who do not know how to respond to an ABD interception may put  themselves and the ABD aircrews at undue risk. The pilot of the suspicious  aircraft in Peru was unaware that he was being called over the radio by the  ABD aircrew. The Letter of Agreement with Colombia requires the  Colombian government to inform the public of the program’s operating  procedures, which the government does through publicly posted notices  and required training courses for pilots and air traffic controllers. The  government also teaches the civilian pilots how to respond to an ABD  interception, as well as the consequences of not complying with the  Colombian Air Force’s commands.
section_title: Program Regularly Reviewed
paragraphs: The program managers that we interviewed said that the program’s  operations are reviewed and evaluated regularly by the program managers  and cognizant U.S. agency officials. For example:   The United States recertifies the program once a year, a process that  serves as the basis for the President’s annual decision on whether to  continue supporting the program. The program was first certified in May  2003 before it could restart and again in July 2004 by a team of  representatives from the Departments of State, Defense, Homeland  Security, Justice, and Transportation. The 2004 certification team  ensured that the major components of the Letter of Agreement— operational procedures, training requirements, logistics support, and  information to civilian pilots—were in place by reviewing official  documents, performing interviews, and observing training and  operational exercises.
The crew of the surveillance aircraft records a video of each ABD  mission once the suspicious aircraft is located. Both Colombian and U.S.  program managers review the video to determine if the checklist was  followed. We reviewed recordings of some ABD missions and observed  the implementation of the safety procedures.
U.S. and Colombian managers of the program meet every six months to  plan for the future and discuss Colombia’s needs for the program. After  the U.S. managers consider Colombia’s needs, they determine whether  to fund the requests for such items as repaving runways at ABD  operating locations.
In addition, the Congress requires an annual report from the President on  the program’s resources and procedures used to intercept drug trafficking  aircraft. The report certifies that the procedures agreed to in the Letter of  Agreement were followed in the interception of aircraft engaged in illegal  drug trafficking during the preceding year.
section_title: Available ABD Program Data Shows Mixed Results, but the Program Lacks Well- Defined Performance Measures
paragraphs: Our analysis of available data—the number of suspicious tracks and law  enforcement activities—indicates that the ABD program’s progress to date  is mixed. The Colombian Air Force surveillance aircraft pursued less than  half of the almost 900 suspicious tracks identified since October 2003 and  few were located. But the number of suspicious tracks appears to have  declined, although the consistency of the suspicious track data is unknown.  The program’s primary objective—to safely force suspicious aircraft to  land so law enforcement authorities can gain control of it—has not  happened very often. In addition, the location of most suspicious tracks has  changed, making them more difficult to locate and intercept.
State/INL does not have clear performance measures that can be used to  help assess the ABD program’s progress toward eliminating aerial drug  trafficking in Colombia. State/INL officials told us that they began  developing measures in early 2005, but they do not contain benchmarks or  timeframes. These same officials said they will meet with Defense shortly  to review data related to these measures for the first time.
subsections: section_title: ABD Program Located Few Aircraft
paragraphs: Since October 2003, the Colombians pursued about 390 out of  approximately 880 suspicious tracks, and located 48 of them (see fig. 1).  Tracks are often difficult to locate because the relocatable over-the-horizon  radar does not provide the suspicious aircraft track’s altitude or the exact  location. Furthermore, according to Colombian Air Force officials, drug  traffickers use hundreds of clandestine airstrips in Colombia. Often the  airstrips are camouflaged and suspicious aircraft are hidden from view.  Therefore, when surveillance aircraft do not interdict suspicious aircraft in  the air, they are unlikely to find them once they land and disappear from  radar.
Recently, the Colombian Air Force asked the United States to permanently  increase the number of flight hours (from 180 to 300 per month) for the  surveillance aircraft to spend more time training and locating clandestine  airstrips. According to U.S. and Colombian officials, once these airstrips  are located, the ABD aircrews can focus on them when searching for a  suspicious aircraft in the area. To date, based on our review of ABD  documents, identification of clandestine airstrips has not assisted in  locating any suspicious aircraft. Some State/INL officials are skeptical that  more flying time, which would increase maintenance and fuel costs, would  produce greater results for the program.
section_title: Suspicious Tracks Reduced, but Accuracy of Count Unknown
paragraphs: The number of suspicious aircraft tracks over Colombia has apparently  declined from approximately 49 to 30 a month, a decrease of about 40  percent, between the first 11 months of the program and the last 11 months  (see fig. 1). According to U.S. and Colombian officials, the reduction in  tracks indicates that the program is deterring drug traffickers from  transporting drugs by air, and is allowing the Colombian government to  meet its goal of regaining control of its airspace, but performance measures  with benchmarks and timeframes linking the reduction of suspicious tracks  to the overall goal have not been developed. Moreover, the accuracy of the  suspicious track data over time is suspect due to the nature of the process,  which relies on some subjective criteria. The process for determining  whether a track is suspicious or legitimate is partly based on the judgment  of JIATF-South and Colombian Air Force personnel, who screen thousands  of tracks every month looking for suspicious movements. For example,  personnel consider whether the aircraft has inexplicably deviated from its  planned flight path or the aircraft’s altitude is unusually low. However, no  definitive criteria exist for such factors, which can therefore be interpreted  differently among operators.
section_title: ABD Missions Lack Involvement of Law Enforcement Personnel
paragraphs: The National Police seldom take control of suspicious aircraft, arrest  individuals suspected of drug trafficking, or seize drugs. Since October  2003, law enforcement was involved in 14 instances (see fig. 2), arresting  four suspects and impounding several aircraft. However, in four of these  instances, the aircraft was already on the ground. Only one ABD mission  resulted in a drug seizure—0.6 metric tons (about 1,300 pounds) of  cocaine. Because State/INL has not established performance measures  regarding law enforcement activities, determining whether the objectives  of the ABD program are being met is difficult. However, State/INL officials  said they would like law enforcement authorities to more often take  control of suspicious aircraft, which may contain drugs, weapons, or cash  that goes unaccounted for if the military or police do not arrive.
As steps on the procedural checklist, ABD personnel contact the  Colombian National Police in Bogotá at the start of an interdiction mission  and prior to firing at the aircraft. But, besides these calls, the Colombian  Air Force usually does not involve the police in ABD missions. Further, the  police face various challenges in reaching the locations where suspicious  aircraft land—often in remote areas of Colombia that are not accessible by  road. The police cannot travel to some locations without additional  resources, including security and transportation, according to INL  officials. But, according to U.S. officials, greater planning and  coordination between the Colombian Air Force and National Police could  enable law enforcement to more frequently take control of suspicious  aircraft. For example, in the February 2005 ABD mission that yielded 1,300  pounds of cocaine, one armed Colombian Navy helicopter provided cover  for another Navy helicopter to land and seize as much cocaine from the  aircraft as it could carry, while the Colombian Army and National Police  arrived later and confiscated the remaining cocaine.
section_title: Changes in Suspicious Tracks Locations Limit Interdiction Capability
paragraphs: In recent months, the majority of suspicious tracks are concentrated along  Colombia’s borders (see fig. 3), making it more difficult for surveillance and  interceptor aircraft to reach the aircraft before it lands or leaves Colombian  airspace. Once a suspicious aircraft lands, surveillance aircraft often have  difficulty locating it.
From November 2003 to July 2005, 141 suspicious tracks were not pursued  by surveillance aircraft because they were near borders or too far away. In  particular, suspicious tracks along Colombia’s southeastern border with  Brazil and Venezuela are at least an hour flight from the closest ABD air  base in Apiay, leaving surveillance and interceptor aircraft little time to find  and intercept a suspicious aircraft before having to refuel (see fig. 4). For  example, one ABD interceptor aircraft, the A-37B Dragonfly, takes 50  minutes to fly to Caruru (about 250 miles) in southeastern Colombia, but it  can remain in that area for only 10 minutes before leaving to refuel. ABD  program managers and safety monitors said it usually takes about 25  minutes to complete an ABD mission when all resources are in place, from  visually locating the aircraft to forcing it to land. However, some ABD  missions have lasted as long as six or seven hours and utilized multiple  surveillance and interceptor aircraft.
section_title: Conclusions
paragraphs: The United States agreed to help Colombia restart the ABD program at the  request of Colombian President Alvaro Uribe. U.S. funding provided for the  program through fiscal year 2005 totals over $68 million; almost $26 million  is proposed for 2006. We found the results of the ABD program mixed.
A primary U.S. concern regarding the program—the safety of the ABD  aircrews and innocent civilians—is addressed in detail in the Letter of  Agreement between the United States and Colombia. However, the  agreement does not include performance measures with benchmarks and  timeframes to help with assessing results. Although State has begun  developing such measures, assessing the program’s effectiveness and  determining whether additional resources might contribute to increased  results is difficult.
Although the number of suspicious aircraft tracks has apparently  declined—from about 49 to 30 per month, the Colombian Air Force seldom  locates the suspicious aircraft. Moreover, drug traffickers do not face a  great risk of being arrested even if they are detected. Out of about 390  suspicious tracks pursued since the start of the program, the Colombian  Air Force located 48; law enforcement or military authorities went to the  scene of 14, including four that were already on the ground. Besides calling  the Colombian National Police during a mission, as required by the  procedural checklist, the Colombian Air Force rarely involves the police.  Without sufficient notice, the police cannot respond quickly and safely to  suspicious aircraft on the ground because much of Colombia is not  controlled by the government. Moreover, many of the suspicious aircraft  tracks detected in recent months are along Colombia’s border regions with  Brazil and Venezuela where ABD aircraft are often too far away to threaten  the trafficking mission.
section_title: Recommendations for Executive Action
paragraphs: First, to help in assessing whether the ABD program is making progress  toward meeting its overall goal of reducing illegal drug trafficking in  Colombia’s airspace, we recommend that the Secretary of State work with  Colombia to define performance measures with benchmarks and  timeframes. These performance measures, as well as results, should be  included in the annual report to the Congress regarding the ABD program.  Second, because the police are seldom involved in ABD missions, we  recommend that the Secretary of State encourage Colombia to seek ways  to more actively involve the National Police. Finally, because many of the  suspicious aircraft tracks are difficult for Colombia to locate and interdict  given the current location of its ABD air bases, we recommend that the  Secretary of State encourage Colombia to establish ABD air bases closer to  the current activity of suspicious aircraft tracks.
section_title: Agency Comments and Our Evaluation
paragraphs: State provided written comments on a draft of this report (see appendix  III). Overall, it found the report to be an accurate assessment of the intent  and execution of the program and noted that it is developing benchmarks  and timeframes for its performance measures. Defense did not provide  written comments. However, neither department commented on our  recommendations. In addition, State and Defense officials provided  technical comments and updates that we incorporated throughout the  report, as appropriate.
As agreed with your office, unless you publicly announce its contents  earlier, we plan no further distribution of this report until 30 days from the  date of this letter. At that time, we will send copies of this report to  interested congressional committees and the Secretaries of State and  Defense. We will also make copies available to others upon request. In  addition, this report will be available at no charge on the GAO Web site at  http://www.gao.gov.
If you or your staff have any questions concerning this report, please call  me at (202) 512-4268 or FordJ@gao.gov. Key contributors to this report  were Al Huntington, Hynek Kalkus, Summer Pachman, and Kerry Lipsitz.  Contact points for our Offices of Congressional Relations and Public  Affairs may be found on the last page of this report.
section_title: ABD Safety Checklist
paragraphs: ander) assumed suspect (UAS)
An ABD mission begins  when relocatable over -the-horizon radar or  other intelligence  sources provide  information about a  suspicious flight to  personnel at the ABD  command center, who  then consider various  questions to determine  whether the track is  involved in illegal drug  trafficking activities.
Once a track is  determined to be  suspicious (checklist  step 1), a surveillance  aircraft, with a crew of Colombian Air Force  personnel and one U.S.  government contractor,  tries to visually locate  it (step 5). The length  of time it takes to find  the suspicious aircraft  can vary.
Once located, the ABD  aircrews try to  determine its identity  and order it to land in  English and Spanish over the radio or  through the use of  visual signals (step 7).   If the suspicious aircraft  continually fails to respond, an ABD  aircrew member gives  a verbal warning that  deadly force will be  used (step 9).
An interceptor aircraft called to the scene,  with a Colombian Air  Force crew, fires warning shots and direct shots if the suspect fails to follow orders (steps 10  and 14). ander)
All use of force by the interceptor is pre- approved by the Commander of the Colombian Air Force.
Abbreviations: ATOI-A track of interest COL-Colombia CNP-Colombian National Police I-Initiates action N-Noted, but no action required RR-Response required SAR-Search and rescue UAS-Unidentified assumed     suspect USG-U.S. government records crash site.
section_title: Scope and Methodology
paragraphs: To review the changes made to the ABD program to address safety  concerns and to determine whether these safeguards were followed, we  reviewed ABD program documentation provided by the Department of  State’s Bureau for International Narcotics and Law Enforcement Affairs  (State/INL) and the Narcotics Affairs Section (NAS) at the U.S. Embassy,  Bogotá, and the Department of Defense’s Joint Interagency Task Force- South (JIATF-South). We also discussed the new safeguards with  knowledgeable U.S. officials at State and Defense in Washington, D.C.;  Bogotá, Colombia; and Key West, Florida; officials from the Colombian  government and Colombian Air Force in Bogotá; and ARINC contractors  located in Bogotá and an ABD air base in Apiay, Colombia. We also  interviewed officials involved in the negotiation of the agreement between  the United States and Colombia prior to restarting the program.
To evaluate the program’s progress in attaining U.S. and Colombian  objectives, we examined data regarding law enforcement activities;  suspicious tracks; aircraft pursued, located, and fired at. This data was  documented by NAS in reports prepared monthly for State/INL containing  the number of missions flown that month and their results. However,  complete data for August and September 2003 was unavailable, and the  data for October 2003 to March 2004 did not include the number of tracks  pursued and identified. By using an event log prepared by NAS with  narratives of ABD missions beginning in August 2003, we extrapolated  some of the data and corroborated all law enforcement activities and  aircraft fired on. We also compared the number of suspicious tracks  recorded by NAS with JIATF-South’s count. The numbers reported were  not the same for most months. We used the NAS count of suspicious tracks  because it is more inclusive of tracks detected by Colombia and does not  include tracks that were later determined to be friendly aircraft. We  interviewed cognizant officials at State/INL, NAS, and JIATF-South about  the data. Further, we discussed the numbers of suspicious tracks with the  Colombian Air Force. Based on our ability to corroborate most of the data  with multiple sources, we determined that it was sufficiently reliable for  our purposes.
We traveled to Colombia in April 2005 and met with NAS officials and other  cognizant U.S. Embassy, Bogotá, officials, and with ARINC managers at  their offices at the Government of Colombia’s Ministry of Defense in  Bogotá. We also visited an ABD air base in Apiay where we met with  ARINC contractors serving as monitors onboard the surveillance aircraft.  Additionally, we visited the Colombian Air Force’s ABD command center in  Bogotá where we interviewed both ARINC contractors and Colombian Air  Force officials. We witnessed the start of an ABD mission at the command  center and reviewed video recordings of previous ABD missions at the U.S.  Embassy.
section_title: Comments from the Department of State
paragraphs: The following are GAO’s comments on the Department of State’s letter  dated August 23, 2005.
subsections: section_title: GAO Comments
paragraphs: 1. State officials provided us draft performance measures for the ABD  program that they told us were developed in April 2005 with  representatives from Defense and the Colombian government.   2. We recognized the U.S. role of program oversight and the Colombian  government’s role of operating and managing the program throughout  the report.   3. We made no substantive changes. This section addressed only the  initial identification of a suspect track. Our analysis found that three of  the six criteria used to determine if a track is suspicious were  subjective. The checklist and other steps taken to further identify  suspect aircraft are discussed elsewhere in the report. 4. We gave examples of the criteria used to determine if an aircraft is  suspected of drug trafficking.  5. A discussion of U.S. government intelligence support to the ABD  program was not within the scope of our report.