REVIEW OF STAFFING AT FAA’S COMBINED 

RADAR APPROACH CONTROL AND TOWER 

WITH RADAR FACILITIES 

Federal Aviation Administration 

Report Number: AV-2007-038 

Date Issued: March 16, 2007 
U.S. Department of 

Memorandum

Transportation 

Office of the Secretary 

of Transportation 

Office of Inspector General 

Subject: ACTION: Review of Staffing at 

FAA’s Combined Radar Approach Control 

and Tower With Radar Facilities 

Federal Aviation Administration 

Report No. AV-2007-038 

Date: March 16, 2007 

From: David A. Dobbs 

Principal Assistant Inspector General 

 for Auditing and Evaluation 

Reply to 

Attn. of: JA-10 

To: Federal Aviation Administrator 

This report presents the results of our review of staffing at combined radar 

approach control and tower with radar facilities. The review was requested by 

Representative James Oberstar, then Ranking Democratic Member of the House 

Committee on Transportation and Infrastructure, and Representative Jerry 

Costello, then Ranking Democratic Member of the House Subcommittee on 

Aviation, after the fatal accident of Comair flight 5191 in Lexington, Kentucky. 

We conducted our review between September 2006 and January 2007. Exhibit A 

contains details on the scope and methodology we used in conducting this review. 

Exhibit B lists the facilities we visited. 

On the morning of August 27, 2006, Comair flight 5191 was scheduled to fly from 

Lexington, Kentucky, to Atlanta, Georgia. Based on preliminary reports, the 

pilots mistakenly taxied onto the wrong runway at Lexington and executed their 

take-off roll. The runway, however, was too short to complete a take-off, and a 

tragic accident occurred that resulted in the loss of 49 passengers and crew. 

Shortly after the accident, media reports surfaced indicating that only one air 

traffic controller was working in the tower at Lexington at the time of the accident. 

According to those reports, the controller was working both tower and radar 

functions combined and reportedly had his back turned to the airfield during 

Comair 5191’s take-off roll. The media also reported that this was contrary to 

Federal Aviation Administration (FAA) policy, which reportedly required that two 

controllers be present in towers that provide both tower control and radar services. 
2

OBJECTIVES 

In an August 30, 2006, letter, Representatives James Oberstar and Jerry Costello 

requested that the Office of Inspector General review the FAA policy that 

reportedly prohibited one controller from performing both radar and tower 

controller duties and determine the extent to which the towers covered by the 

policy were complying with it. A copy of their request is attached as an appendix 

to this report. 

Specifically, Representatives Oberstar and Costello requested the Office of 

Inspector General to determine: 

1. Whether the FAA guidance was written or verbal and how the guidance 

was communicated, 

2. How many towers were not in compliance with the guidance at the time of 

the Comair accident, 

3. How many towers were not in compliance with the guidance at some point 

between the date of the issuance of the guidance and the time of the Comair 

accident, and 

4. What steps FAA took to (a) review staffing at its facilities to determine 

whether they were complying with the guidance and (b) require compliance 

if they were not. 

BACKGROUND 

A combined radar approach control and tower with radar facility is an air traffic 

control terminal that provides radar control to aircraft arriving to and departing 

from the primary airport and adjacent airports and to aircraft transiting in the 

terminal’s airspace. The terminal is divided into two separate functional areas—

radar approach control positions and tower positions. Radar approach control 

positions provide radar control service to aircraft arriving in, departing from, or 

transiting in airspace controlled by the facility, while tower positions control air 

traffic on the surface of airports by giving pilots taxiing and take-off instructions, 

issuing air traffic clearances, and providing separation between landing and 

departing aircraft. These two areas are located within the same facility or in close 

proximity to one another, and controllers rotate between both areas. As of January 

2006, FAA operated 138 combined radar approach control and tower with radar 

facilities. We limited our review to 62 of the 138 facilities. These 62 facilities are 
3

designated Levels 5 through 9 and are most comparable to the Lexington Tower 

(which is a Level 7 tower).1

 

Figure 1. Radar Approach Control and Tower With Radar Facility 

at Abilene, Texas (Level 7) 

Source: Office of Inspector General 

RESULTS IN BRIEF 

We found that FAA’s Vice President of Terminal Services issued verbal guidance 

in late August 2005 regarding staffing at facilities that have combined radar 

approach control and tower with radar functions. This guidance (which was in 

response to an operational error that had occurred at Raleigh-Durham, North 

Carolina, on August 17, 2005) reiterated that during midnight shifts at facilities 

with both radar and tower functions, two controllers should normally be on duty 

performing those responsibilities. 

According to the Vice President for Terminal Services, he expected his area 

directors to disseminate the guidance to their hub managers who in turn would 

disseminate the guidance to individual facility managers. 

We found, however, that because the guidance was verbal, it was misinterpreted 

and inconsistently applied. As a result, staffing on midnight shifts at combined 

radar approach control and tower with radar facilities was not uniformly compliant 

with the guidance established by the Vice President of Terminal Services. On the 

date of the Comair accident, there were 2 additional facilities (for a total of 3 out 

of 62) where only 1 controller was scheduled on the midnight shift—these were in 

Duluth, Minnesota, and Fargo, North Dakota. 

 

1

 FAA air traffic facilities are categorized into multiple levels (5 through 12); the higher the level, the greater the 

demand on a controller’s judgment, skill, and decision-making ability. 
4

We reviewed a statistical sample of 20 randomly selected weeks of staffing data 

for midnight shifts at 15 of the 62 facilities in our universe (a total of 2,100 shifts). 

Our review identified 234 shifts where only 1 controller was scheduled on the 

midnight shift. Based on the results of our sample, we can statistically project 

(with a 95-percent confidence level) that approximately 2,563 or 11.1 percent of 

the 23,002 total midnight shifts (at the 62 facilities in our universe) were staffed 

with only 1 controller between August 28, 2005, and September 2, 2006. 

We did note that the number of non-compliant towers in our sample was higher at 

the beginning of the scope period and then steadily declined as time went on. 

Managers informed us that this occurred because they needed time to analyze the 

operational impact of the guidance on their ability to accomplish needed training 

and grant annual leave. Additionally, managers advised us that they needed to 

consult with their local union to facilitate the schedule change. 

However, we also found that even though two controllers may have been 

scheduled on a midnight shift, there were no assurances that they were both on 

position. We reviewed position logs at each of the facilities we visited. (Position 

logs indicate which tower and radar positions are open during a shift and who is 

actually working those positions). 

During this review, we found evidence suggesting that the radar and ground 

control duties were combined for substantial periods of time even though there 

were at least two controllers on duty. For example, at several facilities, position 

logs we reviewed showed that all positions on midnight shifts were routinely 

combined and the two controllers on duty alternated between working the one 

position and taking breaks. 

Finally, we found that prior to the Comair accident, FAA had no controls in place 

to ensure that facilities had consistently implemented the verbal guidance and 

were uniformly complying with it. Immediately following the Comair accident, 

area directors placed calls to their hub managers who in turn called their facility 

managers to determine the extent to which the guidance had been followed and to 

reiterate its provisions. However, prior to those actions, no formal review of 

compliance had been conducted. 

Since the Comair accident, FAA has formalized the verbal guidance into a written 

order—FAA Notice N JO 7210.639, “Consolidating Control Functions”—

effective November 17, 2006. Formalizing the verbal guidance into written 

requirements is, in our opinion, an appropriate and necessary action. We are 

recommending that FAA communicate all future guidance changing or reiterating 

existing air traffic policies and procedures in writing to ensure uniform 

implementation and compliance. 
5

We are also recommending that FAA develop and implement appropriate policies 

and procedures to ensure that facilities are complying with provisions of FAA 

Notice N JO 7210.639. 

We briefed staff from Representative Oberstar’s and Representative Costello’s 

offices on December 20, 2006, concerning the results of our review. Based on 

discussions at that briefing, we agreed to perform a follow-up review to determine 

if combined radar approach control and tower with radar facilities are complying 

with written provisions contained in FAA Notice N JO 7210.639. 

FINDINGS 

Guidance for Staffing the Midnight Shifts Was Communicated 

Verbally 

We found that the guidance regarding staffing on the midnight shifts was issued 

verbally by FAA’s Vice President of Terminal Services during the week of 

August 28, 2005. The guidance was issued in response to an operational error that 

had occurred at the Raleigh-Durham, North Carolina, air traffic control tower 

earlier in the month. Only one air traffic controller was working at the time of the 

error, and he was working both tower and radar functions combined. In that 

instance, the controller cleared an inbound aircraft to descend into the path of 

another aircraft that had departed the airport, and this action resulted in the 

operational error. 

We met with FAA’s Vice President of Terminal Services in September 2006 to 

obtain a better understanding of the guidance and to determine how the guidance 

was disseminated. During the meeting, he indicated that he was surprised to learn 

that only one controller was working at the time of the error and that he needed to 

reiterate his expectations as to how midnight shift operations should be conducted. 

Accordingly, he briefed the three service area directors who report directly to him 

and instructed them to pass the guidance down through their hub managers and 

ultimately to the local facility managers. According to FAA’s Vice President of 

Terminal Services the guidance essentially stated that: 

At combined radar approach control and tower with radar facilities, two 

controllers should perform the separate functions of tower versus radar. The 

facility manager should either have one controller in the tower (controlling 

aircraft on the surface) and one controller in the approach control (controlling 

aircraft in the air) or the manager could elect to operate the radar function in 

the tower. However, in any event, one controller was required for the tower 

function and a second controller was required for the radar function. The 
6

manager could choose to close down the approach control and bring the radar 

function into the tower. However, if the radar function was brought into the 

tower, then the controller should “come with it.” 

The Vice President of Terminal Services indicated to us that he felt it necessary to 

issue the verbal guidance in order to clarify provisions of FAA Order 7210.3U, 

“Facility Operations and Administration,” issued February 16, 2006. However, 

we found that while the Order contained policies requiring shared responsibility 

for the safe and efficient operation of a facility among all staff, it did not have 

specific requirements regarding staffing during midnight shifts. 

Because the Guidance Was Verbal, It Was Misinterpreted and 

Inconsistently Applied 

We found, that because the guidance was verbal, it was misinterpreted and 

inconsistently applied. As a result, staffing on midnight shifts at combined radar 

approach control and tower with radar facilities was not uniformly compliant with 

the guidance established by the Vice President of Terminal Services. 

Three Towers Were Non-Compliant With the Guidance at the Time of the 

Comair Accident 

As of January 2006, there were 138 combined radar approach control and tower 

with radar facilities in the National Airspace System. Seventy-three of these 

facilities operated 24 hours per day. In order to determine the number of facilities 

that were not in compliance with the guidance at the time of the Comair accident 

(August 27, 2006), we limited our review to 62 facilities that were designated Air 

Traffic Control Level 5 through 9. These 62 facilities are closest in complexity to 

the Lexington, Kentucky, facility (a Level 7 facility). 

To determine if facilities were complying with the guidance on August 27, 2006, 

we contacted each of the 62 radar approach control and tower with radar facilities 

and requested actual staffing data for the midnight shift on that date. Based on our 

review of those data, we found that 3 of the 62 towers (5 percent) were not in 

compliance with the guidance at the time of the Comair accident. They were 

Duluth, Minnesota; Fargo, North Dakota; and Lexington, Kentucky. 
7

Eight of the 15 Towers Sampled Were Non-Compliant With the Guidance 

at Some Point Between When It Was Issued and the Date of the Comair 

Accident 

To determine the number of towers that were not in compliance with the guidance 

at some point between when it was issued and the date of the Comair accident, we 

statistically selected and reviewed 15 of the 62 facilities in our universe. We 

performed site visits at 6 of the 15 facilities. During these visits, we requested and 

reviewed staffing data for 20 randomly selected weeks to determine if the towers 

were in compliance with the guidance. We also reviewed the same 20 weeks of 

staffing data for the 9 facilities that we did not visit; FAA Headquarters provided 

us with those data. 

We found that 8 of the 15 towers in our sample were not in compliance with the 

guidance at some point between when the guidance was issued and the date of the 

Comair accident. Those facilities were: Duluth, Minnesota; Des Moines, Iowa; 

Huntington, West Virginia; Wilkes-Barre, Pennsylvania; Great Falls, Montana; 

Billings, Montana; Abilene, Texas; and Nashville, Tennessee. 

Based on those results, we can statistically project (with a 95-percent confidence 

level) that the number of facilities in our universe of 62 facilities that were not in 

compliance with the guidance at some point during the sampled periods ranged 

between 19 and 47 facilities, with a best estimate of 33 facilities or 53.3 percent of 

the facilities in our universe. 

However, this percentage does not represent how frequently those facilities may 

have had only one controller on duty during a midnight shift. For example, 1 of 

the 15 facilities in our sample had as few as 1 midnight shift staffed with 

1 controller, while another facility in our sample had as many as 133 midnight 

shifts staffed with 1 controller. 

Approximately 11 Percent of all Midnight Shifts at the 62 Facilities Were 

Staffed With Only 1 Controller Between August 2005 and the Date of the 

Comair Accident 

To determine how frequently midnight shifts were staffed with only 1 controller, 

we reviewed 140 days of staffing data for midnight shifts at each of the 

15 facilities in our sample, which totaled 2,100 shifts. Of that amount, we found 

234 non-compliant shifts where only 1 controller was on duty or 11.1 percent of 

the midnight shifts. 

Based on that sample, we can statistically project (with a 95-percent confidence 

level) across all 62 facilities in our universe that there were between 
8

234 (1 percent) and 5,043 (21.9 percent) non-compliant shifts out of a total of 

23,002 midnight shifts from August 28, 2005, to September 2, 2006, with a best 

estimate of 2,563 or 11.1 percent non-compliant shifts. In other words, 

approximately 2,563 or 11.1 percent of the 23,002 total midnight shifts at the 

62 facilities in our universe from August 28, 2005, to September 2, 2006, were 

staffed with only 1 controller. Figure 2 provides the results of our review at the 

15 randomly selected towers. 

Figure 2. Instances of Non-Compliance at the 15 Randomly 

Selected Towers in Our Sample

(Facilities highlighted were non-compliant) 

Facilities 

Reviewed 

Total 

Shifts 

Reviewed

NonCompliant 

Shifts 

1 Dayton* 140 0 

2 El Paso* 140 0 

3 Louisville 140 0 

4 Rochester 140 0 

5 Springfield* 140 0 

6 Syracuse 140 0 

7 Tulsa* 140 0 

1 Abilene* 140 1 

2 Billings 140 2 

3 Great Falls 140 7 

4 Wilkes-Barre/ 

Scranton 

140 14 

5 Nashville 140 16 

6 Huntington* 140 28 

7 Des Moines 140 33 

8 Duluth 140 133 

15 Facilities 2,100 234 

 Source: Office of Inspector General 

*Facility was visited by the Office of Inspector General. 

We did note that the number of non-compliant towers in our sample was higher at 

the beginning of the scope period and then steadily declined as time went on. 

Facility managers informed us that this occurred because they needed time to 

analyze the operational impact of the guidance on their ability to accomplish 

needed training and grant annual leave. Additionally, managers advised us that 

they needed to consult with their local union to facilitate the schedule change. 

Figure 3 demonstrates this trend. 

234 of 2,100 shifts

(11.1 percent) were not 

compliant with the 

guidance. 

8 of 15 facilities 

(53.3 percent) were not 

compliant with the 

guidance. 
9

Figure 3. Number of Non-Compliant Towers out of a Sample of 

15 for 20 Randomly Selected Weeks 

5

7

5

4 4

2 2

1

2

1 1

2

1

2 2

111

2

1

0

1

2

3

4

5

6

7

8

02Oct05 to 08Oct05

09Oct05 to 15Oct05

20Nov05 to 26Nov06

11Dec05 to 17Dec05

01Jan06 to 07Jan06

05Feb06 to 11Feb06

19Feb06 to 25Feb06

05Mar06 to 11Mar06

02Apr06 to 08Apr06

09Apr06 to 15Apr06

16Apr06 to 22Apr06

23Apr06 to 29Apr06

07May06 to 13May06

21may06 to 27May06

28May06 to 03Jun06

11Jun06 to 17Jun06

25Jun06 to 01Jul06

23Jul06 to 29Jul06

20Aug06 to 26Aug06

27Aug06 to 02Sep06

Week of

Number of Non-compliant Towers 

+

Source: Office of Inspector General 

Although Two Controllers May Have Been Scheduled, There Were No 

Assurances That They Were Both on Position 

We also found that even though two controllers may have been scheduled, there 

were no assurances that they were both on position. We reviewed 10 weeks of 

position logs at each of the 6 facilities we visited. The position logs indicate 

which tower and radar positions are open during a shift and who is actually 

working those positions. During this review, we found evidence suggesting that 

the radar and ground control duties were combined for substantial periods of time 

even though there were at least two controllers on duty. The controllers on duty 

were combining all open positions and alternating between breaks and working 

one at a time. For example, at several facilities, position logs we reviewed showed 

that all positions on midnight shifts were routinely combined and the two 

controllers on duty alternated between working the one position and taking breaks. 

Prior to the Accident, FAA Had Not Taken Steps To Ensure That 

Towers Were in Compliance With the Guidance 

Finally, we found that prior to the Comair accident, FAA had no controls in place 

to ensure that facilities had consistently implemented and were uniformly 

complying with the guidance. Immediately following the Comair accident, area 

directors placed calls to their hub managers who in turn called their facility 

managers to determine the extent to which the guidance had been followed and to 
10

reiterate its provisions. However, prior to those actions, no formal review of 

compliance had been conducted. 

Since the Comair accident, FAA has formalized the verbal guidance into a written 

order—FAA Notice N JO 7210.639, “Consolidating Control Functions”—

effective November 17, 2006. The formal policy states the following: 

At facilities where both tower and radar/nonradar approach control services 

are provided, the air traffic manager must ensure, to the maximum extent 

possible, that these functions are not consolidated unless unforeseen 

circumstances or emergency situations arise. . . . 

During midwatch operations (between 2230 and 0630 local time), when 

traffic is very light, all functions may be consolidated for short meal or 

physiological breaks. At facilities with a tower only operation and staffing of 

only one certified professional controller (CPC), coordination must be 

accomplished with the facility providing radar/non-radar approach control 

services to the airport before the CPC can leave the operational quarters for 

physiological breaks. This should only be done during periods of light to 

zero traffic. 

Additionally, facilities have the option of closing the radar operation altogether 

and transferring responsibility for the airspace to a larger facility during the 

midnight shift. 

Formalizing the verbal guidance into written requirements is, in our opinion, an 

appropriate and necessary action. We are recommending that FAA communicate 

all future guidance changing or reiterating existing air traffic control policies and 

procedures in writing to ensure uniform implementation and compliance. 

We are also recommending that FAA develop and implement appropriate 

procedures to ensure that facilities are complying with provisions of FAA Notice 

N JO 7210.639. 

We briefed staff from Representative Oberstar’s and Representative Costello’s 

offices on December 20, 2006, concerning the results of our review. Based on 

discussions at that briefing, we agreed to perform a follow-up review to determine 

if combined radar approach control and tower with radar facilities are complying 

with written guidance contained in FAA Notice N JO 7210.639. 
11

RECOMMENDATIONS 

We recommend that FAA: 

1. Communicate all future guidance changing or reiterating existing air traffic 

policies and procedures in FAA Order 7210.3U, “Facility Operation and 

Administration,” in writing to ensure uniform implementation and 

compliance. 

2. Develop and implement appropriate procedures to ensure that facilities are 

complying with provisions of FAA Notice N JO 7210.639, “Consolidating 

Control Functions.” 

MANAGEMENT COMMENTS 

We provided FAA’s Vice President of Terminal Services with a copy of our draft 

report on February 16, 2007. He agreed with the facts as presented in our report 

and generally concurred with our findings and recommendations. 

ACTIONS REQUIRED 

In accordance with Department of Transportation Order 8000.1C, we would 

appreciate receiving your written comments within 15 business days. Please 

indicate the specific action taken or planned for each recommendation and the 

target date for completion. 

We appreciate the courtesies and cooperation of FAA representatives during this 

audit. If you have any questions concerning this report, please call Robin Hunt, 

Acting Assistant Inspector General for Aviation and Special Program Audits, at 

(415) 744-0420 or Dan Raville, Program Director, at (202) 366-1405. 

# 

cc: FAA Deputy Administrator 

ATO Chief Operating Officer 

FAA Chief of Staff 

Anthony Williams, ABU-100 

Martin Gertel, M-1 
12 

Exhibit A. Scope and Methodology 

EXHIBIT A. SCOPE AND METHODOLOGY 

This audit was conducted in accordance with Government Auditing Standards

prescribed by the Comptroller General of the United States and included such tests 

as we considered necessary to provide reasonable assurances of detecting abuse or 

illegal acts. The following scope and methodology were used in conducting this 

review. 

To identify the FAA guidance regarding air traffic controller staffing during 

midnight shifts at combined radar approach control and tower with radar facilities 

performing both radar work and ground duties, we interviewed FAA’s Vice 

President of Terminal Services and FAA’s Director of Terminal Safety. We also 

interviewed the Directors of FAA’s Terminal Service Area Directorates to 

determine when they became aware of the guidance and to determine what steps 

each Director took to ensure the facilities in their Directorates were complying 

with the guidance. 

We interviewed hub managers to determine when they became aware of the 

guidance and to determine what steps they took to ensure that the facilities in their 

hubs were in compliance with the guidance. Finally, we interviewed facility 

managers at each facility we visited to determine when they became aware of the 

guidance and what steps they took to comply with it. 

We contacted FAA to determine the number and type of facilities affected by the 

guidance. Per FAA, as of January 2006, there were 138 FAA combined radar 

approach control and tower with radar facilities, and 73 of the 138 facilities 

operated 24 hours a day. FAA air traffic facilities are categorized into multiple 

Air Traffic Control levels (5 through 12); the higher the level, the greater the 

demand on a controller’s judgment, skill, and decision-making ability. 

In order to answer the congressional request, we elected to test 62 of the 

73 facilities. These 62 facilities are designated Levels 5 through 9 and are most 

comparable to the Lexington Tower, which is a Level 7 tower. We elected not to 

include facilities designated as Levels 10 through 12 in our review because their 

higher traffic levels and complexity make it far less likely that only 1 controller 

would be scheduled to work during midnight hours. 
13 

Exhibit A. Scope and Methodology 

We statistically selected 15 of the 62 facilities to review. Those facilities are listed 

in table 1. 

Table 1. Sample of 15 Facilities Reviewed 

Source: Office of Inspector General 

We performed site visits at 6 of the 15 facilities during the weeks of 

October 16, 2006, and October 30, 2006. (Before beginning this review, we also 

visited Roanoke Regional Airport to obtain an understanding of the data used. 

Roanoke was not included in the statistical sample and is not included in the 

analysis of the 15 sites selected). See exhibit B for a listing of the six facilities we 

visited. 

During these visits, we also requested and reviewed staffing data for the 

20 randomly selected weeks shown in table 2 to determine if the facilities were in 

compliance with the guidance during our scope period of August 28, 2005, 

through September 2, 2006. 

Facility ID Facility Name City State ATC Level

GTF Great Falls International Airport Great Falls MT 5

DLH Duluth International Airport Duluth MN 6

HTS Tri-State/Milton J. Ferguson Field Airport Huntington WV 6

ABI Abilene Regional Airport Abilene TX 7

AVP Wilkes-Barre/Scranton International Airport Wilkes-Barre/Scranton PA 7

BIL Billings Logan International Airport Billings MT 7

DSM Des Moines International Airport Des Moines IA 7

ELP El Paso International Airport El Paso TX 7

SGF Springfield-Branson Regional Airport Springfield MO 7

DAY James M Cox Dayton International Airport Dayton OH 9

ROC Greater Rochester International Airport Rochester NY 8

SYR Syracuse Hancock International Airport Syracuse NY 8

BNA Nashville International Airport Nashville TN 9

SDF Louisville International-Standiford Field Airport Louisville KY 9

TUL Tulsa International Airport Tulsa OK 9
14 

Exhibit A. Scope and Methodology 

Table 2. 20 Randomly Selected Weeks 

Sample No Beginning of W eek End of W eek

1 Sunday, 02 October 2005 Saturday, 08 October 2005

2 Sunday, 09 October 2005 Saturday, 15 October 2005

3 Sunday, 20 November 2005 Saturday, 26 November 2005

4 Sunday, 11 December 2005 Saturday, 17 December 2005

5 Sunday, 01 January 2006 Saturday, 07 January 2006

6 Sunday, 05 February 2006 Saturday, 11 February 2006

7 Sunday, 19 February 2006 Saturday, 25 February 2006

8 Sunday, 05 March 2006 Saturday, 11 March 2006

9 Sunday, 02 April 2006 Saturday, 08 April 2006

10 Sunday, 09 April 2006 Saturday, 15 April 2006

11 Sunday, 16 April 2006 Saturday, 22 April 2006

12 Sunday, 23 April 2006 Saturday, 29 April 2006

13 Sunday, 07 May 2006 Saturday, 13 May 2006

14 Sunday, 21 May 2006 Saturday, 27 May 2006

15 Sunday, 28 May 2006 Saturday, 03 June 2006

16 Sunday, 11 June 2006 Saturday, 17 June 2006

17 Sunday, 25 June 2006 Saturday, 01 July 2006

18 Sunday, 23 July 2006 Saturday, 29 July 2006

19 Sunday, 20 August 2006 Saturday, 26 August 2006

20 Sunday, 27 August 2006 Saturday, 02 September 2006

Source: Office of Inspector General 

We reviewed the same 20 weeks of staffing data for the 9 facilities (in our sample 

of 15) that we did not visit. Those data were provided by FAA Headquarters. 

We interviewed facility managers at each location we visited to determine staffing 

levels and traffic counts on the midnight shift and obtain their views on 

implementation of the staffing guidance. We also interviewed union 

representatives at each of the six facilities we visited to obtain their view on how 

the implementation of the guidance had impacted staffing at the facility. 

We obtained and reviewed position logs from the six facilities we visited to 

validate the reliability of the staffing data for each facility. The position logs 

indicate which tower and radar positions are open during a shift and who is 

actually working those positions. We also listened to tapes of conversations 

between controllers and pilots during the midnight shift to validate if information 

on the position logs were valid. At some facilities, we reviewed time and 

attendance records to validate the number of controllers on duty during a midnight 

shift. 

We observed operations during the midnight shift and reviewed traffic count data 

for the midnight shift to determine the amount of activity on the midnight shift. 
15 

Exhibit B. Facilities Visited 

EXHIBIT B. FACILITIES VISITED 

• Tri-State/Milton J. Ferguson Field, Huntington, West Virginia 

• Abilene Regional Airport, Abilene, Texas 

• El Paso International Airport, El Paso, Texas 

• Springfield-Branson Regional Airport, Springfield, Missouri 

• James M Cox Dayton International Airport, Dayton, Ohio 

• Tulsa International Airport, Tulsa, Oklahoma 
16 

Exhibit C. Major Contributors 

EXHIBIT C. MAJOR CONTRIBUTORS 

Daniel Raville Program Director 

Angela McCallister Project Manager 

Marshall Jackson Senior Analyst 

Benjamin Huddle Analyst 

Tasha Thomas Analyst 

Petra Swartzlander Statistician 

Andrea Nossaman Writer-Editor 
Appendix. Congressional Request 

17

APPENDIX. CONGRESSIONAL REQUEST 

Mr. Todd Zinser 

Acting Inspector General 

U.S. Department of Transportation 

Washington, D.C. 20590 

Dear Mr. Zinser: 

There have been some disturbing reports in the wake of the August 27, 2006 Comair 

Flight 5191 crash in Lexington, Kentucky. This terrible tragedy resulted in the deaths of 49 

people, and the media has reported, and the Federal Aviation Administration (FAA) has 

confirmed, that the Blue Grass Airport air traffic control tower was understaffed at the time 

of the accident. 

Air traffic controllers are an important component to the safe operation of our 

nation’s air traffic system, and their effectiveness requires proper staffing levels at each 

facility. It was reported that in November 2005, an overloaded controller at the Raleigh, 

North Carolina airport directed two planes too close to one another, and this close call 

prompted the FAA to issue “guidance” forbidding air traffic controllers with certain 

responsibilities from working alone. 

An FAA statement of August 29, 2006, states that some air traffic control towers 

which control surface traffic also “separate airborne aircraft using radar equipment. FAA 

guidance is to provide individual controllers for the radar and control tower functions.” It is 

not clear whether this guidance is written or verbal. The statement further indicates that this 

guidance was not followed at the Lexington tower where the manager decided to have “one 

controller handle both functions during the overnight shift.” While the National 

Transportation Safety Board has yet to issue a full report of its findings regarding the causes 

of the Comair Flight 5191 accident, it is not too early to investigate how widely the staffing 

practice at the Blue Grass Airport is practiced at other critical air traffic control facilities 

across the nation. 
18

Appendix. Congressional Request 

Mr. Todd Zinser 

Page 2 

Therefore, we would like your office to review the November 2005 FAA guidance, 

and determine the extent to which the towers covered by the guidance are complying with it. 

Was the “guidance” written or verbal? If verbal, how was it communicated? How many 

towers were not in compliance at the time of the Comair accident, and how many were not in 

compliance at some point between the dates of the issuance of the guidance and the accident? 

What steps did FAA take to review staffing at its facilities to determine whether they were 

complying with the guidance, and to require compliance if they were not? 

If, in the course of your work, you identify other relevant issues that you believe the 

Congress should be aware of, we would like you to include them in your analysis. 

Should you have any questions or need any additional information, please contact 

Stacie Soumbeniotis, Democratic Staff Director, or John Drake, Democratic Professional 

Staff, of the Subcommittee on Aviation at (202) 225-9161. 

Sincerely, 

James L. Oberstar Jerry F. Costello 

 Ranking Democratic Member Ranking Democratic Member 

 Committee on Transportation Subcommittee on Aviation 

 and Infrastructure 
The following pages contain textual versions of the graphs and charts found in this 

document. These pages were not in the original document but have been added here 

to assist screen readers. 
Report on the Review of Staffing at the Federal Aviation Administration’s Radar 

Approach Control and Tower with Radar Facilities. 

Section 508 Compliant Presentation 

Figure 2. Instances of Non-Compliance at the 15 Randomly Selected Towers in Our 

Sample 

Facilities 

Reviewed 

Total 

Shifts 

Reviewed

NonCompliant 

Shifts 

1 Dayton 140 0 

2 El Paso 140 0 

3 Louisville 140 0 

4 Rochester 140 0 

5 Springfield 140 0 

6 Syracuse 140 0 

7 Tulsa 140 0 

1 Abilene 140 1 

2 Billings 140 2 

3 Great Falls 140 7 

4 Wilkes-Barre/ 

Scranton 

140 14 

5 Nashville 140 16 

6 Huntington 140 28 

7 Des Moines 140 33 

8 Duluth 140 133 

15 Facilities 2,100 234 

Source: Office of Inspector General 

• The facilities that the Office of Inspector General visited: Dayton, El Paso, 

Springfield, Tulsa, Abilene, and Huntingdon. 

• 8 of 15 facilities (53.3 percent) were not compliant with the guidance. These 

facilities were Abilene, Billings, Great Falls, Wilkes-Barre/Scranton, Nashville, 

Huntington, Des Moines, and Duluth. 

• 234 of 2,100 shifts (11.1 percent) were not compliant with the guidance. 
Figure 3. Number of Non-Compliant Towers out of a Sample of 15 for 20 Randomly 

Selected Weeks 

Week 

Sample 

Number 

Dates for Sample Week Number of Non-Compliant 

Towers 

1 October 2, 2005 to October 8, 2005 5 

2 October 9, 2005 to October 15, 2005 7 

3 November 20, 2005 to November 26, 2005 5 

4 December 11, 2005 to December 17, 2005 4 

5 January 1, 2006 to January 7, 2006 4 

6 February 5, 2006 to February 11, 2006 2 

7 February 19, 2006 to February 25, 2006 2 

8 March 5, 2006 to March 11, 2006 1 

9 April 2, 2006 to April 8, 2006 2 

10 April 9, 2006 to April 15, 2006 1 

11 April 16, 2006 to April 22, 2006 1 

12 April 23, 2006 to April 29, 2006 2 

13 May 7, 2006 to May 13, 2006 1 

14 May 21, 2006 to May 27, 2006 2 

15 May 28, 2006 to June 3, 2006 2 

16 June 11, 2006 to June 17, 2006 1 

17 June 25, 2006 to July 1, 2006 1 

18 July 23, 2006 to July 29, 2006 1 

19 August 20, 2006 to August 26, 2006 2 

20 August 27, 2006 to September 2, 2006 1 

Source: Office of Inspector General 
Table 1. Sample of 15 Facilities Reviewed 

Source: Office of Inspector General 

Table 2. 20 Randomly Selected Weeks 

Sample 

Number 

Beginning of Week End of Week 

1 Sunday, 02 October 2005 Saturday, 08 October 2005 

2 Sunday, 09 October 2005 Saturday, 15 October 2005 

3 Sunday, 20 November 2005 Saturday, 26 November 2005 

4 Sunday, 11 December 2005 Saturday, 17 December 2005 

5 Sunday, 01 January 2006 Saturday, 07 January 2006 

6 Sunday, 05 February 2006 Saturday, 11 February 2006 

7 Sunday, 19 February 2006 Saturday, 25 February 2006 

8 Sunday, 05 March 2006 Saturday, 11 March 2006 

9 Sunday, 02 April 2006 Saturday, 08 April 2006 

10 Sunday, 09 April 2006 Saturday, 15 April 2006 

11 Sunday, 16 April 2006 Saturday, 22 April 2006 

12 Sunday, 23 April 2006 Saturday, 29 April 2006 

13 Sunday, 07 May 2006 Saturday, 13 May 2006 

14 Sunday, 21 May 2006 Saturday, 27 May 2006 

15 Sunday, 28 May 2006 Saturday, 03 June 2006 

16 Sunday, 11 June 2006 Saturday, 17 June 2006 

17 Sunday, 25 June 2006 Saturday, 01 July 2006 

18 Sunday, 23 July 2006 Saturday, 29 July 2006 

19 Sunday, 20 August 2006 Saturday, 26 August 2006 

20 Sunday, 27 August 2006 Saturday, 02 September 2006 

Source: Office of Inspector General 

Facility 

Identification 

Facility Name City State Air Traffic 

Control Level 

GTF Great Falls International Airport Great Falls Montana 5 

DLH Duluth International Airport Duluth Minnesota 6 

HTS Tri-State/Milton J. Ferguson Field Airport Huntington West Virginia 6 

ABI Abilene Regional Airport Abilene Texas 7 

AVP Wilkes-Barre/Scranton International Airport WilkesBarre/Scranton Pennsylvania 7 

BIL Billings Logan International Airport Billings Montana 7 

DSM Des Moines International Airport Des Moines Iowa 7 

ELP El Paso International Airport El Paso Texas 7 

SGF Springfield-Branson Regional Airport Springfield Missouri 7 

DAY James M. Cox Dayton International Airport Dayton Ohio 9 

ROC Greater Rochester International Airport Rochester New York 8 

SYR Syracuse Hancock International Airport Syracuse New York 8 

BNA Nashville International Airport Nashville Tennessee 9 

SDF Louisville International-Standiford Field 

Airport 

Louisville Kentucky 9 

TUL Tulsa International Airport Tulsa Oklahoma 9