Automatic Dependent SurveillanceBroadcast/Cockpit Display of Traffic 

Information: Innovations in Aircraft 

Navigation on the Airport Surface

O. Veronika Prinzo

Civil Aerospace Medical Institute

Federal Aviation Administration

Oklahoma City, OK 73125

July 2004

Final Report

This document is available to the public

through the National Technical Information

Service, Springfield, VA 22161.

 

Office of Aerospace Medicine

Washington, DC 20591

DOT/FAA/AM-04/11
NOTICE

This document is disseminated under the sponsorship of

the U.S. Department of Transportation in the interest of

information exchange. The United States Government

assumes no liability for the contents thereof.
i

Technical Report Documentation Page 

1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. 

DOT/FAA/AM-04/11 

4. Title and Subtitle 5. Report Date 

July 2004 Automatic Dependent Surveillance - Broadcast/Cockpit Display of Traffic 

Information: Innovations in Aircraft Navigation on the Airport Surface 6. Performing Organization Code 

7. Author(s) 8. Performing Organization Report No. 

Prinzo OV

9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) 

11. Contract or Grant No. 

FAA Civil Aerospace Medical Institute 

P.O. Box 25082 

Oklahoma City, OK 73125 

12. Sponsoring Agency name and Address 13. Type of Report and Period Covered 

Office of Aerospace Medicine 

Federal Aviation Administration 

800 Independence Ave., S.W. 

Washington, DC 20591 14. Sponsoring Agency Code 

15. Supplemental Notes 

This work was performed under Task AM-B-00-HRR-516. 

16. Abstract: 

In 2000, the FAA’s Office of Runway Safety made a concerted effort to reduce runway incursions. The Safe 

Flight 21 Program awarded contracts for CDTI avionics development and an operational demonstration that 

included a surface moving-map capability. An operational evaluation was conducted in October 2000 to assess 

pilot use of varying types of CDTI devices and how surface-map information could aid pilot situation 

awareness when taxiing. Complex taxi routes were designed to examine how well pilots navigated their aircraft 

using an electronic surface-map display (north-up, track-up) or a paper surface map. This study was designed to 

determine how the use of these displays might aid situational awareness and influence operational

communications. Pilots navigated their aircraft during 3 day and 2 night operations, resulting in 31 structured 

and 37 unstructured taxi routes. As subject-matter experts listened to 15 hours of audiotapes and read verbatim 

transcripts, they identified operational concerns and noted problems. Communications involved in progressive 

taxi routes and routes instructing pilots to follow another aircraft were excluded from analysis. A Type-of-Route 

x Type-of-Map ANOVA revealed that more problems occurred for structured, compared with unstructured 

taxi routes, and more messages were exchanged. A statistically significant interaction indicated that most 

problems occurred for the north-up map during structured taxi routes, and the number of problems 

encountered was comparable for the other maps when pilots navigated along unstructured taxi routes. When 

designing electronic surface-map displays, providing a north-up map orientation appears to create more 

problems than either track-up or paper surface maps — especially when taxi routes are complex (or unfamiliar). 

17. Key Words 18. Distribution Statement 

Document is available to the public through the 

National Technical Information Service 

Pilot Communication, ATC Communication, 

Air Traffic Control, CDTI, ADSB 

Springfield, Virginia 22161 

19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price 

Unclassified Unclassified 18 

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized 

1

AUTOMATIC DEPENDENT SURVEILLANCE - BROADCAST / COCKPIT

DISPLAY OF TRAFFIC INFORMATION: INNOVATIONS IN

AIRCRAFT NAVIGATION ON THE AIRPORT SURFACE

 “What a fog! Plane been buzzin’ around overhead for the last half hour. Must be like trying to find your way 

through the inside of a cow. I never did see such a country. Even the birds are walkin’.” — A Guy Named Joe, complaining about the weather at the airfield 

in Scotland (1943). Dalton Trumbo, U.S. screenwriter.

Recreational and professional pilots form a diverse 

population of aviators who vary in piloting skills, experience with airport operations, and familiarity with the 

surface geography of their departure and destination 

airports. At one time or another, they – like all of us 

– make mistakes. Sometimes, adverse weather or poor 

visibility add complexity and contribute to human error. 

The more serious mistakes can result in runway incursions, surface incidents, near-collision ground incidents, 

and fatal runway collisions.

In its special-investigation report entitled Runway Incursions at Controlled Airports in the United States (May 6, 

1986), the National Transportation Safety Board (NTSB) 

noted a significant increase in collision ground incidents.1

That report included several new safety recommendations 

to reduce the frequency of runway incursions. Some of 

these recommendations remained open when, on January 18, 1990, a fatal runway collision involving a Boeing 

727 and a Beechcraft King Air Al00 occurred at Atlanta, 

Georgia. As a result, the NTSB placed airport runway 

incursions on its “1990 Most Wanted Transportation 

Safety Improvements List,” where it still remains. 

The FAA is working diligently to address NTSB 

Safety Recommendation A-00-66 (NTSB, 2000): 

“... require, at all airports with scheduled passenger 

service, a ground movement safety system that will 

prevent runway incursions; the system should provide 

a direct warning capability to flight crews. In addition, 

the FAA should demonstrate through computer simulations or other means that the system will, in fact, 

prevent incursions.”2 A critical component of Safety 

Recommendation A-00-66 is that runway incursion prevention technologies should “provide a direct warning 

capability to flight crews.” 

In 2000 and again in 2002, the FAA’s Office of Runway 

Safety made a concerted effort to reduce runway incursions. Several technologies are being developed that will 

provide a direct alerting capability to flight crews include 

ground markers, addressable signs, and surface moving 

maps. Under the Safe Flight 21 Program, contracts were 

awarded for avionics development and demonstration that 

included a surface moving-map capability. This capability 

was demonstrated (along with several others) in October 

2000 during an operational evaluation of the automatic 

dependent surveillance broadcast (ADS-B) and cockpit 

display of traffic information (CDTI) at the Standiford 

International Airport (SDF) in Louisville, Kentucky. 

The FAA’s intent in undertaking technology operational evaluation activities is to refine, standardize, and 

certify a set of tools that airports can acquire to address 

their specific runway safety issues. In line with the FAA’s 

intent, the stated purposes of the Louisville, Kentucky, 

operational evaluation were to develop and evaluate specific ADS-B air-air and air-ground applications, evaluate controller use of ADS-B, and demonstrate ADS-B 

technology. It also provided an opportunity to collect 

field data that could be used to guide the development 

of the ADS-B airport surface movement applications. 

These applications would improve surface surveillance 

and navigation for the pilot through enhancements to 

airport surface situational awareness. 

There were several goals associated with the airport 

surface situational awareness application that were being 

addressed. One goal was to enhance safety and mitigate 

occasions for runway incursion by providing pilots with 

tools that graphically display the proximate location of 

other surface aircraft and vehicles moving about the airport. Another goal was to enhance pilots’ positional awareness of their aircraft on the airport surface by providing 

them with tools that displayed real-time information to 

supplement out-the window speed, direction, and position 

information. The FAA envisions that CDTI applications 

may improve the efficiency and safety of surface operations 

at busy, (or unfamiliar) controlled airports.

The objectives of the operational evaluation for the 

airport surface situational awareness application were to 

assess how effective CDTI was in increasing pilot awareness of other like-equipped ADS-B aircraft and vehicles on 

the airport surface and to evaluate different levels of CDTI 

map capabilities as aids to surface situational awareness. 

To evaluate how ADS-B and surface-map information 

could be used to aid pilot situational awareness while on 
2 

the airport surface, very specific and complex taxi routes 

were created. Each taxi route was designed to examine 

how well flight crews navigated their aircraft along the 

assigned taxi route using either an electronic surface-map 

display, such as the example displayed in Figure 1, or a 

paper surface map.

During the five-day event, objective (air traffic control 

voice tapes and radar data) and subjective data (surveys, 

questionnaires, jump-seat observer reports, small-group 

interviews) were collected from controller and pilot participants. This report provides a general description of the 

communication findings for airport-surface situational 

awareness. Due to time constraints, these findings were 

not available for inclusion into the final comprehensive 

report prepared by the Operational Evaluation Coordination Group (FAA, 2001), the flight deck observer data 

report prepared by Joseph, Domino, Battiste, Bone, and 

Olmos (2003), or the preliminary “quick-look” report 

prepared by Livack, McDaniel, and Battiste (2001).

METHOD

Participants

Twenty-five paid pilot volunteers flew 16 different aircraft. Two controllers and a coordinator (also volunteers) 

provided local- and ground-control services. They were 

on a temporary detail during training and on a regular 

schedule during the evaluation.

Materials

Experimentally Constructed Structured Taxi Routes 

and Taxi-Route Cards. The experimentally constructed 

taxi routes (structured taxi routes) described the routes 

necessary for pilots to navigate a defined course segment 

to or from the assigned runway. These defined, complex 

taxi routes were created exclusively for the operational 

evaluation. Pilots received individual uniquely labeled 

cards with these “canned” taxi routes presented in text 

format. Each card had a named taxi route associated with it 

(e.g., CUPS1, FBO1, ANG1) that provided very specific, 

and often complex, taxi instructions for portions of the 

outbound and inbound taxi routes. Each structured route 

was presented on a single sheet of paper, as in the example 

presented in Figure 2 (left panel). Ground controllers 

received these structured routes as a graphical image with 

the name of the taxi route clearly labeled across the card, 

as shown in the right panel of Figure 2.

Traditional Unstructured Taxi Routes. A majority 

of the airport surface operations were performed using 

established taxi patterns and procedures to and from the 

assigned runway and designated parking areas. For these 

unstructured, typical taxi routes, the ground controller verbally provided pilots with the instructions and 

frequency information necessary for the pilots to taxi 

their aircraft to or from the assigned runways. Pilots 

did not know in advance the taxi routes they would be 

Figure 1. Example of a Moving Map Display With an Airport Surface Map Overlay.
3

Figure 2. An Example of a Structured Inbound Taxi Route to Fixed Base Operations (FBO). 

 FBO 2 Structured Taxi Route: 

On Ground frequency off RWY 

17R: ACID taxi to parking via 

the FBO2 routing. Hold short of 

RWY 17L at Delta. Contact 

ATC to continue clearance. 

ROUTE:

• Exit RWY on Bravo 3 

• TL on Bravo 

• TR on Golf 

• TL on Joulette 

• TR on Mike 

• TL on RWY 11/29 

• TR on November 

• TL on Foxtrot 

• TL on Papa 

• TR on RWY 11/29 

• TL on Golf 1 

• TL on Golf 

• TR on November 

• TR on Delta 

• TL on Delta 6 

• Hold short at Delta 

• TL on Echo 

• TL to ramp area 

Legend: TL = Turn Left TR = Turn Right

FBO 2 STRUCTURED TAXI ROUTE

given. Also, there were no unstructured taxi-route cards 

that could serve as memory aids as they navigated these 

unstructured taxi routes.

Digitized Audiotapes. The Terminal Radar Approach 

Control (TRACON) facility provided five digital audiotapes (DATs), one for each test period. Each DAT 

contained separate voice records of all the transmissions 

made on the radio frequency assigned to the Ground 

East, Local West, or Final Radar West position on the 

left channel. The right channel contained the Universal 

Time Coordinated (UTC) time code expressed in date, 

hour (hr), minute (min), and whole second (s). The 

NiceLoggerTM Digital Voice Recorder System (DVRS) 

decoded and displayed time and correlated it with the 

voice stream in real time. The data consisted of 15 hrs 

of digitized voice communications, of which 6 hr were 

from the Ground East position.

Procedure

During the operational evaluation, the tower was 

divided into two sections, with the West portion of the 

airspace dedicated to the evaluation. In addition, a portion of the airfield was set apart from normal operations, 

and tower controllers limited access to the West runway 

to participating aircraft. The experimental flight periods 

were scheduled during normally low airport activity. 

The operational evaluation involved five flight periods 

that included a varying number of aircraft that participated in morning (Flight Period 1 = 11 aircraft, Flight 

Period 2 = 13 aircraft, Flight Period 4 = 6 aircraft) or 
4 

night (Flight Period 3 = 4 aircraft, Flight Period 5= 14 

aircraft) operations. Flight periods lasted between 2 hr 

19 min and 2 hr 59 min.

A majority of the airport surface operations were 

performed using customary taxi procedures3 using the 

unstructured taxi routes — following initial call-up,) 

ground controllers issued a taxi clearance such as the 

one found in FAA Order 7710.65M Air Traffic Control 

(2000): “American Four Ninety Two, Runway Three Six 

Left, taxi via taxiway Charlie, hold short of Runway Two 

Seven Right.” However, for some portions of the taxi route, 

the participating ground controllers instructed the pilots 

who participated in the evaluation of the airport surface 

situational application to proceed outbound or inbound 

according to the script-defined taxi routes —using the 

structured taxi route cards (e.g., CUPS1, FBO1, ANG1). 

The distance, the numbers of turns, and the complexity 

of the inbound and outbound taxi routes were controlled. 

Examples of the communications for structured and unstructured routes are presented in Figure 3.

Prior to each flight period, participating ground controllers attended an activity briefing. They were instructed 

to clear participating aircraft via customary taxi routes 

(i.e., unstructured taxi routes) or defined structured taxi 

routes and monitor the aircraft’s movement along its assigned taxi route to ensure compliance with the scripted 

scenario and FAA procedures. 

Speaker ID Message 

Structured Taxi Route

FBO 7 Structured Taxi Route 

N123 LOUISVILLE GROUND NOVEMBER ONE TWO THREE READY FOR TAXI 

ATC NOVEMBER ONE TWO THREE ROGER TAXI VIA FBO SEVEN HOLD SHORT OF 

RUNWAY ONE SEVEN LEFT AT ECHO 

N123 FBO SEVEN HOLD SHORT OF ONE SEVEN LEFT AT ECHO NOVEMBER ONE 

TWO THREE 

ATC NOVEMBER ONE TWO THREE CROSS RUNWAY ONE SEVEN LEFT TAXI TO 

RUNWAY ONE SEVEN RIGHT VIA FBO SEVEN 

N123 CROSS ONE SEVEN LEFT AND TAXI TO RUNWAY ONE SEVEN RIGHT FBO 

SEVEN NOVEMBER ONE TWO THREE 

Unstructured Taxi Route

N321 LOUISVILLE GROUND NOVEMBER THREE TWO ONE READY FOR TAXI 

ATC NOVEMBER THREE TWO ONE LOUISVILLE GROUND RUNWAY ONE SEVEN 

RIGHT TAXI VIA ECHO FOUR HOLD SHORT OF ONE SEVEN LEFT AT ECHO 

FOUR

N321 HOLD SHORT OF ONE SEVEN LEFT AT ECHO FOUR NOVEMBER THREE TWO 

ONE 

ATC NOVEMBER THREE TWO ONE CROSS RUNWAY ONE SEVEN LEFT TURN LEFT 

ON DELTA 

N321 CROSS ONE SEVEN LEFT TURN LEFT ON DELTA NOVEMBER THREE TWO ONE 

ATC NOVEMBER THREE TWO ONE TURN RIGHT AT TAXIWAY GOLF RIGHT ON 

BRAVO FOR RUNWAY ONE SEVEN RIGHT 

N321 RIGHT ON GOLF RIGHT ON BRAVO TO ONE SEVEN RIGHT NOVEMBER THREE 

TWO ONE 

Figure 3. Examples of Pilots and Controller Communications by Type of Taxi Route.
5

Pilots participated in proficiency training exercises 

prior to the evaluation and attended pre-flight briefings 

before each event. During these briefings they received a 

set of taxi-route cards to use when ATC issued structured 

taxi-route clearances. They were instructed to interpret the 

textual route information presented on their taxi-route 

cards to determine the route to taxi. For example, following initial radio contact with November One TwentyThree, the ground controller provided the pilot with the 

taxi clearance, “November one twenty-three Louisville 

Ground taxi via FBO TWO hold short of runway one 

seven left at delta six.” Using the assigned taxi-route card 

for FBO2, the pilot navigated inbound to the fixed base 

operation spot 2. 

Pilots taxied their aircraft along their assigned routes using Paper-Charts (35 segments), Track-up (11 segments) or 

North-up (22 segments) surface map overlays to find their 

way to the runway, ramp, or transient parking area. Each 

outbound taxi segment lasted between 530.0 s and 1763.0 

s (M=1289.0 s, SE=89.11 s) during 9 structured routes and 

from 292.0 s to 1652.0 s (M=717.4 s, SE=59.8 s) during 

20 unstructured routes. Each inbound taxi segment lasted 

between 520.0 s and 1321.0 s (M=734.82 s, SE=57.0 s) for 

22 structured routes and from 134.0 s to 470.0 s (M=280.1 

s, SE=64.8 s) for 17 unstructured routes.

Experimental Design

This study used a two-factor, between-groups design. 

The between-groups factors were Taxi Route (Structured, 

Unstructured) and Type of Surface Map (Paper-Chart, 

North-up, and Track-up). Each structured and unstructured taxi route segment was assigned to a different, 

pre-selected flight-crew as part of their outbound or 

inbound taxi segment. 

The type of ADS-B equipment installed in each aircraft 

determined its assignment to a Type of Map group. Nine 

aircraft comprised the Paper-Chart Group. They could 

display ADS-B equipped aircraft on their CDTI, but no 

map overlay was available of the airport surface. Five of the 

aircraft had scanned Jeppesen airport surface map overlays 

on their CDTI, always depicted in a north-up orientation. 

They were classified as the North-up Group. The remaining 

two aircraft were classified as the track-up group, since their 

aircraft had a CDTI with a vector-based moving map of 

the airport surface map available for display. The messages 

recorded during the structured and unstructured routes 

allowed for a comparison with taxi performance by the 

Paper-Chart, North-up, and Track-up Groups.

Dependent Measures

Operational efficiency for each structured and unstructured taxi segment was of primary interest. It consisted 

of two components: communication workload and 

operational communications. Measures of communication workload included number and duration of communication. Measures of operational communication 

included problems and operational concerns.

To measure changes in communication workload and 

operational communication for each taxi segment, the 

messages transmitted between the ground controller and 

pilot of each aircraft were grouped into transactional communication sets (TCSs) that began with the pilots’ first 

message to the ground controller and the last message 

that either switched the pilot to local control (outbound) 

or terminated at the ramp or transient parking area (inbound). TCSs are made up of several communication sets 

that each consists of all the messages that are transmitted 

between a controller and pilot and share a common goal 

or purpose (Prinzo 1996). 

To illustrate, consider the partially encoded transcript 

presented in Figure 4. There are two transactional communication sets, one for each of two different taxi operations. Taxi #1, which is an outbound taxi, consists of two 

communication sets: a taxi route clearance (messages 1, 

2, and 4) and transfer of communications (messages 12 

through 14). Taxi #2 is comprised of three communication sets: position report (message 3), taxi route clearance 

(messages 5 through 11), traffic advisory (messages 10 

and 11). Message 10 is complex, in that the first part of 

the message is a traffic-advisory while the latter part is a 

taxi instruction.

Objective Measures of Communication Workload.

Four measures of communication workload were examined for each transactional communication set. They included (1) number of messages transmitted, (2) time on 

frequency per message (TOF), (3) frequency occupancy 

time (FOT), and (4) time under ground control (TGC). 

They were computed for each transactional communication set that began with the pilot’s initial call-up and 

ended with the last recorded transmission.

As shown in Figure 4, six messages involved N123AB 

(TCS #1). The TOF for the first message was 4 s. Frequency 

occupancy time for TCS #1 was computed as the sum of 

the TOF. In the example, FOT was 17 s (FOT = Σ TOF 

= 4+2+1+5+3+2). As shown by the solid-line arrow, the 

time N123AB spent under ground control (time ground 

control, TGC) was computed as the time lapsed from the 

onset of the pilot’s initial call-up in message 1 (at 4219 

s) to the closing of the transaction in message 14 (at 

4489 s). In the example, TGC was 270 s (4489 s - 4219 

s). Computation of the TGC for N321CD is shown by 

the use of the dashed-line arrow, and it was 72 s. A taxi 

segment typically began with a pilot checking in and 

ended in the transfer of communication to local control 

(outbound route), as was the case with TCS #1, or with 

the last recorded transmission as the pilot navigated back 
6

4219 270

4228 072

2

153

4489 24300

Time (in seconds) 

Message

#

TCS

#

Com 

Set # SID Message Onset Offset TOF TGC 

1 1 1 N123AB LOUISVILLE GROUND CONTROL THIS IS NOVEMBER ONE TWO THREE 

ALFA BRAVO READY TO TAXI 

4223 4 

2 1 1 ATC NOVEMBER ONE TWO THREE ALFA BRAVO TAXI TO RUNWAY ONE 

SEVEN LEFT 

4224 4226 

3 2 2 N321CD GROUND CITATION THREE TWO ONE CHARLIE DELTA IS WITH YOU AT 

FOXTROT CLEAR OF ONE SEVEN LEFT 

4232 4 

4 1 1 N123AB THREE ALFA BRAVO TAXI TO ONE SEVEN LEFT 4233 4234 5 2 2 ATC CITATION ONE CHARLIE DELTA TURN LEFT AT THE END LEFT ON GOLF 

HOLD SHORT OF TAXIWAY ECHO 

4236 4240 4 

6 2 2 N321CD LEFT AT THE END LEFT ON GOLF HOLD SHORT OF ECHO ONE CHARLIE 

DELTA 

4241 4244 3 

7 2 2 N321CD YOU WANT ME TO CROSS THERE AT ELEVEN TWO NINE 4248 4250 2 8 2 2 ATC ONE CHARLIE DELTA CROSS ELEVEN TWO NINE HOLD SHORT OF ECHO 

ON GOLF 

4251 4254 3 

9 2 2 N321CD CHARLIE DELTA SHORT OF ECHO ON GOLF 4255 4256 1 

10 2 2,3 ATC CITATION ONE CHARLIE DELTA TRAFFIC TWO TRUCKS ON ECHO 

THEY'LL BE TURNING RIGHT ON GOLF PASS BEHIND THEM THEN TAXI TO THE RAMP 

4291 4296 5 

11 2 2,3 N321CD OKAY BEHIND THE TRUCKS AND TO THE RAMP ON ECHO BEHIND THEM 4297 312 1 4 N123AB LOUISVILLE GROUND NOVEMBER ONE TWO THREE ALFA BRAVO AT 

RUNWAY ONE SEVEN LEFT HOLD SHORT READY FOR DEPARTURE 

4473 4478 

13 1 4 ATC THREE ALFA BRAVO CONTACT TOWER AT ONE TWO FOUR POINT TWO 4481 4484 14 1 4 N123AB ALFA BRAVO SWITCHING TO TOWER ONE TWO FOUR POINT TWO 4487 

Figure 4. Example of a Transcript Encoded into Transactional Communication Sets.
7

to either the ramp or transient parking area (inbound), 

which was the case with TCS #2. 

Measures of Operational Communications. Communications that have the potential to adversely affect 

operational efficiency were identified and classified as 

problems and operational concerns. Problems included 

message reception (say again, did you copy), misunderstanding (readback error, stolen transmission, intentional 

repetition of a previous message for emphasis), erroneous 

information (incorrect call sign, can’t find route segment 

provided in taxi instructions), and message production

(self-correction of the call sign or another piece of information during transmission). Operational concerns 

involved spatial and positional awareness. Spatial awareness includes a general understanding of the geography of 

the airport surface, whereas positional awareness relates 

more to the temporal and relational factors associated 

with maneuvering about the airport. Examples of spatial 

awareness (aircraft is not on its assigned route, correction 

made to a previous taxi instruction, incorrect taxi clearance 

issued, instructions given to rejoin route, confusion, lost, 

missed turn) and positional awareness (maneuver around 

aircraft, possible conflict, request clearance to cross an 

active runway) are presented in Figure 5.

In summary, message count, contents, and duration 

were the objectively derived measures of communication workload and operational communication extracted 

from the time-stamped voice tapes. They were used to 

compute descriptive statistics expressed as means (M) and 

standard errors (SE) that summarized CDTI electronic 

(north-up, track-up) versus paper-chart surface-map use 

on operational efficiency between ATC and the participating flight crews. Operational communication in the 

form of problems and operational concerns provided some 

insights and implications for future air traffic operations, 

workload, and communications procedures.

Qualifications, Training, and Data Encoding Procedures

This section begins with a description of the qualifications of the subject-matter experts (SMEs) and continues 

with the procedures used by the lead SME to train the 

other SMEs. The section ends with an explanation of the 

data-encoding process.

Qualifications of the Subject-Matter Experts. The 

lead air traffic SME was an instrument-rated pilot and 

former controller who had worked as an FAA Academy 

instructor for 8 years and had worked for 12 years in 

FAA supervision and management. Two additional air 

traffic SMEs had been instructors (Terminal Option) at 

the FAA Academy in Oklahoma City. The pilot subjectmatter expert was a recently retired airline pilot with 31 

years of experience. Prior to serving as an SME, he was an 

instructor on the B-727 and DC-8 aircraft; check airman 

on the DC-9 aircraft; and pilot of the CV-880, DC-8, 

B-727, DC-9, L-1011, B-757 and B-767 aircraft.

Training Subject-Matter Experts. The lead SME 

provided the other SMEs with 16 hours of training on 

the data-encoding process to achieve consistency and 

conformity in identifying communication transactions 

and evaluating the accuracy of content. Since OpEval-2 

imposed minor operational constraints, SMEs received 

instruction on how to evaluate communications in light 

of those modifications. Furthermore, the lead SME encouraged the other SMEs to direct their attention to 

the detection and codification of any benefits that may 

have occurred from the pilots having access to a CDTI. 

In addition to identifying positive outcomes, they also 

were asked to comment on any situation involving a 

potential or real loss of separation or situational awareness, misunderstanding, or problem (missed readback 

of the identifiers, routes, altitudes, etc.). Finally, the 

SMEs received instruction on how to select and enter 

their codes onto the OpEval-2 Aviation Topics Speech 

Acts Taxonomy-Coding Form (see Prinzo, Britton, & 

Hendrix, 1995, for details).

Data Encoding. Once taught, each SME received a 

complete set of audiocassettes, transcripts, and the code 

and instruction manual. The audiotapes and transcripts 

aided the SMEs in the identification of communication 

sets for each inbound and outbound taxi segment. Each 

SME worked independently to identify and code the 

efficiency and accuracy of communications. However, 

they met on a weekly basis to discuss their encoding 

and to resolve any differences. Once the SMEs reached 

consensus, the data entry clerks received the final copy, 

and it was entered into the database for final analysis.

RESULTS

Operational communications from ADS-B/CDTI 

were evaluated from verbatim transcripts and digitized 

voice recordings provided by the TRACON facility. 

Although requests were made during the planning of 

the event that baseline circuits be included during 

the evaluation, none were conducted. Consequently, 

comparisons between the routine and communication 

protocol developed for pilot use during the evaluation 

could not be performed since the baseline data necessary 

for comparison were not included as part of the operational evaluation. The analysis of voice tapes did allow for 

preliminary comparisons between flight crews who had 

access to traditional paper-charts and electronic airport 

surface maps, in either a north-up or track-up orientation, 

as aids to their surface situational awareness.
8 

Types of Problems Example 

Message Reception

Did you copy SIX TWO FOUR MIKE TANGO GROUND YOU COPY 

Say again SAY AGAIN 

Misunderstanding

Readback error NO THAT'LL BE A RIGHT TURN ON DELTA ... 

Intentional repetition I SAY AGAIN TAXI VIA THE CUPS THREE B ROUTE 

Stolen transmission NEGATIVE THAT WAS NOT FOR NOVEMBER ONE TWO 

THREE THAT WAS FOR RESCUE ONE TWO THREE ... 

Erroneous Information

Incorrect call sign OKAY THAT WAS UPS TWO TWELVE 

Can't find route segment provided 

in taxi instructions 

YOU TOLD US TO HOLD SHORT KILO AND NOVEMBER 

WE DON'T SEE A KILO ON OUR LISTING... 

Message Production

Self-correction of call sign during 

transmission 

BONANZA NINE TWO CORRECTION PIPER NINE TWO 

ZERO JUST CONTINUE WEST ... 

Self-correction during 

transmission 

MAKE A LEFT TURN ON RUNWAY CORRECTION MAKE 

A LEFT TURN ON TAXIWAY DELTA ... 

Types of Operational Concerns Example 

Spatial Awareness

Aircraft is not on its assigned 

route 

WE'RE ON PAPA AND WE WANT TO BE ON HOTEL ... 

Correct a previous taxi instruction AMEND THAT - HOLD SHORT OF TAXIWAY NOVEMBER 

ON HOTEL 

Incorrect taxi clearance issued FBO SIX HOLD SHORT OF THE RIGHT AND I BELIEVE 

FBO SIX'S INSTRUCTION IS TO TAKE US TO ONE 

SEVEN RIGHT CAN YOU VERIFY YOU WANT US TO 

TAKE FBO SIX BRAVO

Instructions given to rejoin route TURN LEFT ON PAPA REJOIN YOUR ROUTE AT ... 

Confusion NO CROSS BRAVO TURN LEFT ON CHARLIE ... 

Lost GROUND ... AS YOU CAN SEE WE'RE LOST 

Missed turn WE MISSED A TURN THERE WE'RE TAXI LEFT NOW ... 

Position Awareness

Maneuver around aircraft/vehicle ARE YOU GOING TO BE ABLE TO GET BY THAT VAN 

Possible conflict CROSS RUNWAY ONE SEVEN LEFT WITH NO DELAY 

TRAFFIC TWO MILES OUT 

Request clearance to cross an 

active runway 

GROUND CONFIRM WE'RE STILL CLEARED TO CROSS 

THREE FIVE RIGHT 

Figure 5. Examples of Problems and Operational Concerns.
9

The analyses were restricted to inbound and outbound 

taxi routes that either began or ended at the ramp or 

transient parking areas. All inbound taxi routes began 

with the pilot being clear of the runway and ended at the 

ramp or transient parking area. All outbound taxi routes 

began from the ramp or transient parking areas and ended 

to the runway of take-off. Furthermore, taxi routes that 

included “progressive taxi,” “follow traffic” instructions, 

or instructed pilots to taxi their aircraft back to the same 

runway they just exited for another departure were excluded. Since progressive ground movement instructions 

include step-by-step routing directions, these taxi routes 

were excluded because pilot variance in navigating on the 

airport surface would be restricted since ground control 

would be providing detailed instructions to guarantee safe 

and expeditious flow to the destination point. There were 

727 messages (pilots=401, controllers=326) transmitted 

between participating pilots and controllers during the 31 

structured and 37 unstructured taxi routes that involved 

39 inbound and 29 outbound taxi segments.

Communication Workload

Multivariate Analysis of Variance (MANOVA) was 

performed on the taxi-segment means for each objective 

measure of communication workload presented in Table 

1 (standard errors (SE) are enclosed in parentheses). Univariate Analysis of Variance (ANOVA) was used to assess 

the statistically significant findings. The Tukey Honestly 

Significant Difference (HSD) statistic was performed on 

statistically significant main effects and interactions. An 

alpha level of .05 was set for all statistical tests.

A two-way Type-of-Route by Type-of-Map MANOVA 

revealed a statistically significant main effect for Type of 

Route [F (4,59)=9.76] and Type-of-Route by Type-ofMap interaction, [F(8,118)=6.85]. Subsequent Univariate 

ANOVAs revealed that not only were more messages 

transmitted during structured (M=12.70 SE=.99) compared with unstructured (M=8.82 SE=.87) taxi routes 

[F(1,62)=8.72], but more time was spent under the authority of the ground controller (Structured M=953.25 

SE=55.73, Unstructured M=508.03 SE=49.22) 

[F(1,62)=35.86]. Although the time on frequency to 

transmit individual messages did not vary with the type 

of route navigated [F(1,62)=2.09], pilots and controllers jointly increased their overall frequency occupancy 

time by 9 s during the structured (M=41.24 SE=3.22) 

compared with unstructured (M=32.34 SE=2.84) taxi 

routes, [F(1,62)=4.29].

The Type-of-Route by Type-of-Map interaction revealed that the type of route navigated, in combination 

with the type of map available on the flight deck, affected 

communication workload for the number of messages 

transmitted [F(2,62)=5.70], frequency occupancy time 

[F(2,62)=4.48], and time spent under the authority of 

ground control [F(2,62)=25.02]. In particular, Tukey 

post hoc comparisons clearly indicated that controllers 

and pilots in the north-up surface map group exchanged 

twice as many messages during the structured routes, as 

compared with unstructured routes.

Statistically significant differences between the northup surface map group for structured as compared with 

unstructured taxi routes (using Tukey post hoc comparisons) also revealed that participants in this group 

spent nearly twice as long communicating during the 

structured, as opposed to unstructured taxi routes, and 

were under the authority of ground control for an additional 18 mins (1084.52 s). Tukey results also showed 

that participants in the north-up surface map group who 

Table 1. Objective Measures of Communication Workload 

Measures of Communication Workload, in seconds (Standard Error) 

Source TOF N Messages FOT TGC 

Structured Taxi Route 

Paper-chart 3.24 (.25) 11.00 (1.13) 35.89 (3.69) 0716.67 (063.88) 

North-up 3.51 (.37) 16.50 (1.70) 52.63 (5.54) 1383.88 (095.81) 

Track-up 3.59 (.47) 10.60 (2.14) 35.20 (7.00) 0759.20 (121.19) 

Unstructured Taxi Route 

Paper-chart 3.64 (.25) 11.24 (1.16) 36.82 (3.80) 688.24 (065.73) 

North-up 3.67 (.28) 07.71 (1.28) 27.86 (4.18) 299.36 (072.43) 

Track-up 4.28 (.43) 07.50 (1.96) 32.33 (6.39) 536.50 (110.63) 
10 

Table 2. Frequency of Problems Presented by Type of Route by Type of Map 

Type of Map 

Paper-chart Track up North up 

Types of Problems (n=38) S U S U S U Total % 

Message Reception 5.3% 10.6% 5.3% 2.6% 7.9% 7.9% 39.4%

Misunderstandings 5.3% 5.3% 2.6% 2.6% 15.8%

Erroneous Information 2.6% 2.6% 5.3%

Message Production 05.3% 10.6% 2.6% 2.6% 13.1% 34.2%

Intentional Repetition 2.6% 2.6% 005.3%

Total Percentage 21.1% 31.6% 7.9% 5.3% 27.3% 10.5% 100.0%

Note: S = Structured Taxi Route and U = Unstructured Taxi Route 

Table 3. Frequency of Operational Concerns Presented Type of Route by Type of Map

Type of Map 

Paper-chart Track up North up 

Types of Operational Concerns 

 (n=33) S U S U S U Total % 

Spatial Awareness 

Aircraft is not on its assigned route 03.0% 06.1% 03.0% 012.1%

Correction to taxi instructions 03.0% 03.0% 006.1%

Incorrect taxi clearance issued 06.1% 006.1%

Instructions given to rejoin route 03.0% 06.1% 009.1%

Lost 06.1% 006.1%

Missed turn 03.0% 03.0% 06.1% 012.1%

Position Awareness 

Maneuver around aircraft 03.0% 003.0%

Possible conflict 03.0% 03.0% 03.0% 03.0% 012.1%

Request cleared to cross a runway 15.2% 09.1% 03.0% 03.0% 03.0% 033.3%

Total Percentage 33.3% 15.1% 15.0% 03.0% 27.3% 06.0% 100.0%

Note: S = Structured Taxi Route and U = Unstructured Taxi Route
11

traveled via structured taxi routes also exchanged more 

messages than those in the track-up surface map group 

that navigated the unstructured taxi routes. They also 

spent more time on frequency than the track-up surface 

map group during structured taxis and spent more time 

under the authority of ground control than any of the 

other participating groups, regardless of their assigned 

type of taxi route. The north-up surface map group that 

navigated unstructured taxi routes spent the least amount 

of time under the authority of ground control.

Operational Communications

Previous research has demonstrated that when attentional resources are taxed, people may fail to detect 

that another person is talking, they may misspeak or 

mishear, or experience other problems identified from 

communication (Navarro, 1989). To gain some insights 

as to how the combination of the type of route navigated 

and type of map available on the flight deck affected communication workload, an examination of the operational 

communications was initiated.

Types of Problems. The types of problems, along with 

their frequency of occurrence, are presented in Table 2. 

Approximately 40% of the problems involved aspects of 

message reception that took the form of a request either 

from a pilot to have a transmission repeated (say again) 

or a controller request for confirmation that a message 

was received (did you copy). Another 16% of the problems involved misunderstandings. They involved pilots 

incorrectly repeating back information transmitted in a 

previous message (readback error) or pilots acting upon 

an instruction that was meant for someone else (stolen 

transmission). Erroneous information involved 5.2% of 

the problems, taking the form of an incorrectly spoken 

aircraft call sign and pilot failure to find a taxi intersection. A fourth group, mid-stream corrections, consisted 

of mid-utterance repairs that involved either the aircraft’s 

call sign or taxi information, and they included 34.2% 

of the identified problems. The final type of problem 

involved the purposeful repetition or restatement of an 

earlier transmission, and it occurred 5.3% of the time. 

In each recurrence, the controllers instructed the pilots 

to navigate their aircraft along the assigned taxi routes 

or runways. 

Types of Operational Concerns. The types of operational concerns, along with their frequency of occurrence, 

are presented in Table 3. The operational concerns noted 

in the data involved either spatial awareness (aircraft is 

not on its assigned route, correction to taxi instructions, 

incorrect taxi clearance issued, instructions given to rejoin 

route, lost, missed turn) or positional awareness (maneuver around aircraft, possible conflict, request cleared to 

cross a runway). Approximately 75% of the operational 

concerns were related to spatial awareness, while the 

remaining 25% centered on position awareness.

Prevalence of Problems and Operational Concerns.

Before examining the data for problems and operational 

concerns, a chi-square (χ2) test revealed no statistically 

significant difference in the number of structured, compared with unstructured taxi routes completed, when 

pilots had available either the paper-chart, track-up or 

north-up surface maps [χ2(2)=1.24]. Of the 68 taxi 

routes, 37 contained one or more problems. Subsequent 

chi-square tests revealed a significant difference in the 

number of problematic routes among pilots in the northup surface map group [χ2

(1)=12.57]— 100% of their 

structured (8/8) and 21% of their unstructured (3/14) 

taxi routes were problematic. The number of problematic routes was equivalent when pilots navigated their 

assigned structured or unstructured taxi routes with 

paper-charts (Structured=11/18 Unstructured=10/17) 

or track-up (Structured=3/5 Unstructured=2/6) surfacemap displays.

A two-way Type-of-Route by Type-of-Map ANOVA 

was performed on the total number of problems and 

operational concerns associated with each assigned taxiroute clearance. As shown in Figure 6, more problems 

and operational concerns were present during the structured, as compared with the unstructured taxi routes 

[F(1,62)=9.82]. The Type-of-Route by Type-of-Map interaction also was statistically significant [F(2,62)=3.90]. 

Subsequently, the Tukey HSD statistic revealed significantly more overall problems; operational concerns resulted only for the north-up surface-map group during 

structured taxi routes, compared with the north-up and 

track-up surface map groups during unstructured taxi 

routes. Five of the 9 identified problems occurred during 

eight taxi operations and involved mid-stream corrections, 

three centered on problems in message reception, and one 

involved an incorrect readback of a taxi clearance. Eight 

of the 9 identified operational concerns involved spatial 

awareness (missed turn = 2, aircraft not on its assigned 

route =1, ATC issued instructions to rejoin a route = 2, 

incorrect taxi clearance issued = 2, and correction to taxi 

instructions = 1), and one concerned position operation 

(e.g., a pilot request to cross an active runway). 

DISCUSSION

The analysis of voice communications that compared 

flight crews who had access to traditional paper-charts 

and electronic airport surface maps, in either a north-up 

or track-up orientation, as aids to their surface situational 

awareness revealed that the combination of the type of 
12 

assigned taxi route and surface map capability onboard 

the aircraft affected communication workload. Notably, 

participants in the north-up surface map group a) exchanged more messages than the track-up surface map 

group when they navigated the unstructured taxi routes, 

b) spent more time on frequency than the track-up surface 

map group during the structured taxi condition, and c) 

spent more time under the authority of ground control 

than the other groups regardless of their assigned taxi 

route (structured or unstructured). 

Of the 68 taxi routes completed, 54% contained one 

or more operational concerns or problems — with more 

overall problems noted by the SMEs for participants in 

the north-up surface map group during the structured 

taxi routes, when compared with the north-up and trackup surface map groups during unstructured taxi routes. 

Notably, all of the structured and 21% of the unstructured 

taxi routes that involved the use of a north-up display 

were problematic. The number of problematic routes was 

equivalent when pilots navigated their assigned structured 

or unstructured taxi routes using paper-charts or a trackup surface-map display.

To illustrate the types of communication and navigational problems experienced by participants in the 

north-up map group, a transactional communication set 

is presented in Figure 7. It is comprised of eight transactions. 

The first four transactions were non-eventful and involved 

establishing contact (messages #1-2), issuing a taxi route 

clearance (messages #2-3), an instruction to hold short of 

an active runway (messages #2-3), and a clearance to cross 

that runway (messages #8-9). The first problem appeared 

in Transaction 5 when the ground controller observed 

that N123AB missed a turn (message #10), which was 

acknowledged by the pilot (message 11). About 20 s later, 

Transaction 6 began with the ground controller providing 

instructions to the pilot on how to rejoin FBO7B to runway 

35L (message #11). Transaction 7 began with the ground 

controller instructing the pilot to hold short of taxiway 

Mike (message #14), at which point the pilot requested 

confirmation that N123AB was the intended recipient of 

that message (message #15). Such a request suggested that 

the pilot might not have been actively monitoring the radio 

frequency. Transaction 8 was comprised of messages #20-23, 

involving an expedited taxi operation and a confirmation 

of message receipt from the pilot by the ground controller. 

The entire transactional communication set took 1289 s 

to complete (21.48 m) and contained three operational 

concerns (missed turn, crossing an active runway, and an 

expedited taxi) and two problems (say again, did you copy) 

that required the repetition of previously transmitted messages and additional radio frequency time.

The results of the Wickens, Liang, Prevett, and Olmos 

(1996) simulations study, which investigated pilot use of 

either a rotating or fixed map display for conducting an 

approach to a landing, reported that access to a north-up 

display was not advantageous for pilots who were flying 

southerly headings — any changes to their flight path would 

require them to perform complex mental rotations. Their 

interpretation correlates well to the findings reported here 

in that approximately 75% of the identified operational 

concerns were related to spatial awareness. That is, for pilots 

in the north-up map group, more problems were experienced that related to missing a turn or attempting to rejoin 

their taxi route. For participants in the paper-chart group, 

problems took the form of getting lost; for the track-up 

map group, it was not being on their assigned route.

-0.5

0

0.5

1

1.5

2

2.5

3

Structured Unstructured

Type of Taxi Route

Mean Problems and Concerns 

Type of Map

 North-up

 Track-up

 Paper-chart

Figure 6. Combined Mean Total of Problems and Operational Concerns 

Presented by Type of Route and Type of Map.
13

6

TCS # Message

#

Reply 

Time 

(s) 

SID Message 

1 01 — N123AB ALFA BRAVO'S READY TO TAXI 

1,2,3 02 002 ATC ONE TWO THREE ALFA BRAVO LOUISVILLE GROUND ROGER 

RUNWAY THREE FIVE LEFT TAXI VIA FBO SEVEN BRAVO 

HOLD SHORT OF RUNWAY THREE FIVE RIGHT 

2,3 03 002 N123AB OKAY TAXI TO THREE FIVE LEFT VIA FBO BRAVO FBO SEVEN 

BRAVO AND HOLD SHORT OF THREE FIVE RIGHT 

3 04 169 ATC NOVEMBER THREE ALFA BRAVO HOLD SHORT OF RUNWAY 

THREE FIVE RIGHT 

3 05 001 N123AB BRAVO 

3 06 007 N123AB ALFA BRAVO HOLDING SHORT 

3 07 000 ATC ROGER 

4 08 450 ATC NOVEMBER THREE ALFA BRAVO CROSS RUNWAY THREE 

FIVE RIGHT AT DELTA SIX 

4 09 002 N123AB BRAVO CROSS THREE FIVE RIGHT AT DELTA SIX THANK YOU 

5 10 068 ATC NOVEMBER THREE ALFA BRAVO LOOKS LIKE YOU MISSED 

YOUR TURN THERE TURN RIGHT THERE AT YOUR NEXT 

TAXIWAY THEN A RIGHT ONTO PAPA 

5 11 001 N123AB OKAY UNDERSTAND SORRY 

6 12 020 ATC THREE ALFA BRAVO TURN RIGHT THERE INTO PAPA THEN A 

LEFT TURN NOVEMBER START TO REJOIN YOUR ROUTE 

THERE 

6 13 001 N123AB OKAY NOW WE GOT IT 

7 14 202 ATC NOVEMBER THREE ALFA BRAVO HOLD SHORT OF MIKE 

7 15 004 N123AB WAS THAT FOR THREE ALFA BRAVO 

7 16 144 ATC AFFIRMATIVE HOLD SHORT OF ALFA OPPOSITE DIRECTION 

TRAFFIC 

7 17 002 N123AB BRAVO 

7 18 000 ATC THREE ALFA BRAVO CONTINUE 

7 19 002 N123AB ALFA BRAVO THANK YOU 

8 20 025 ATC NOVEMBER THREE ALFA BRAVO EXPEDITE YOUR TAXIING 

ON BRAVO TO THREE FIVE LEFT THAT TRAFFIC TO FOLLOW 

YOU 

8 21 002 ATC NOVEMBER THREE ALFA BRAVO DID YOU COPY 

8 22 113 N123AB THREE ALFA BRAVO WE'RE EXPEDITING 

8 23 010 ATC THANK YOU 

Figure 7. Transcript of an Outbound Taxi Segment with Operational Concerns. 
14 

It would seem that having a north-up map display 

for navigating the airport surface provided no additional 

benefit over that of a paper chart. The findings suggest 

that the pilots in the paper-chart and north-up map 

groups also may have been busier performing complex 

mental operations (i.e., making left to right transformations) while navigating their aircraft along their assigned 

taxi route. As the data show, pilots in each of these two 

map groups requested a higher number of repetitions of 

previously spoken messages and were more likely to read 

back messages incorrectly. Consequently, fewer attentional 

resources would have been available to actively listen for 

their aircraft’s call sign on the radio.

This is similar to driving on an unfamiliar metropolitan 

interstate highway requiring extra vigilance to make a 

timely and correct turn when approaching a fast-moving, 

cloverleaf intersection. If a passenger should attempt to 

engage the driver in casual conversation, the driver might 

miss the turn or not hear the passenger. The driver and 

pilot alike can request a “say again” or ask for assistance 

– both requiring additional communications.

Although some pilots (like drivers) turn their maps 

to be congruent with the direction they are going, the 

observer data reported by Joseph et al. (2002) did not 

mention whether jump-seat observers noted that pilots 

in the paper-chart group had rotated their maps or not. 

If the pilots manually rotated their paper maps to simulate a track-up surface-moving map, their performance 

should have been more aligned with that of the pilots in 

the track-up group instead of the north-up group.

When evaluating emerging avionics devices that aid 

pilots to quickly detect, avoid, monitor, and follow other 

aircraft, consideration as to the electronic format of these 

displays must be deliberated in light of the piloting task 

the operator is expected to perform (see Aretz, 1991, 

for a summary of previous research; Carel, McGarth, 

Hersherber, & Herman, 1974, for early research on 

design criteria). The format in which a map is presented 

can, and does, affect some aspects of pilot performance 

— north-up displays are better for some tasks (planning), 

and track-up displays are better at others (turning). In 

fact, data presented by Clarke, McCauley, Sharkey, Dingus, and Lee (1996) suggest that, when both north-up 

and track-up displays are available, pilots typically select 

a north-up map display when planning a route and a 

track-up display when flying. Some developers are making 

both north-up and track-up modes available on some of 

their CDTI devices, and this provides the pilot with the 

option to select one mode for some piloting tasks and 

the other mode for others. Of course, some pilots still 

may choose to use paper charts as their primary source 

of airport information.

REFERENCES

Aretz, A. (1991). The design of electronic map displays. 

Human Factors, 33, 85-101.

Carel, W.L., McGarth, J.J., Hershberger, M.L. and 

Herman, J.A. (1974). (DOD-74-731101). Design 

criteria for airborne map displays volume I: Methodology and research results. Washington DC: Department of Defense, Department of the Navy, Office 

of Naval Research.

Clarke, D.L., McCauley, M.E., Dingus, T.A., and Lee, 

J.D. (1996). Development of human factors guidelines 

for advanced traveler information systems and commercial vehicle operations: Comparable systems analysis.

Washington, DC: Federal Highway Administration 

(FHWA-RD-95-197).

Federal Aviation Administration. (Nov 2002). Order 

7050.1 Runway Safety Program. [On-line]. Available: www.awp.faa.gov/ops/aws600/runway/2002

RunwaySafetyOrder7050-1.pdf.

Federal Aviation Administration. (July 2002). Runway 

Safety Blueprint 2002-2004. [On-line]. Available: 

www.faa.gov/runwaysafety/publications.cfm. 

Federal Aviation Administration. (2001). Operational 

Evaluation-2 Final Report. [On-line]. Available: 

www1.faa.gov/And/AND500/docmgr/docs/

T0247.pdf.

Federal Aviation Administration (2000). Air Traffic Control (7110.65M). Washington DC: U.S. Government Printing Office.

Federal Aviation Administration (1998). Airport Surface 

Operations Safety Action Plan. [On-line]. Available: 

www1.faa.gov/ats/ato/150_docs/RSP_AP.DOC.

Joseph, K.M., Domino, D. Battiste, V., Bone, R., and 

Olmos, O. (2003). A Summary of Flightdeck Observer Data from SafeFlight 21 OpEval-2. (DOT/

FAA/AM-03/2). Washington, DC: Federal Aviation 

Administration, Office of Aerospace Medicine.4

Livack, G.S., McDaniel, J.I., and Battiste, V. (March 2001). 

Airport Surface Moving Map Displays: OpEval-2 Evaluation Results and Future Plans. [On-line]. Available: 

adsb.tc.faa.gov/WG6_Meetings/Meeting4/242AWP-4-09%20Surface%20Map.pdf.

National Transportation Safety Board. (July 6, 2000). 

NTSB Safety Recommendation A-00-66. [On-line]. 

Available: http://www.ntsb.gov/Recs/letters/2000/

A00_66_71.pdf.
15

National Transportation Safety Board. (1986). Runway 

Incursions at Controlled Airports in the United States.

(NTSB-SIR-86-01). NTIS Order Number PB86-

917003. 

Prinzo, O.V. (1996). An analysis of approach control/pilot 

voice communications. (DOT/FAA/AM-96/26). 

Washington, DC: Federal Aviation Administration, Office of Aerospace Medicine.4

Prinzo, O.V., Britton, T.W. and Hendrix, A.M. (1995). 

Development of a coding form for approach control/

pilot voice communications. (DOT/FAA/AM-95/

15). Washington, DC: Federal Aviation Administration, Office of Aerospace Medicine.4

Wickens, C.D., Liang, C., Prevett, T., and Olmos, O. 

(1996). Electronic maps for terminal area navigation: Effects of frame of reference and dimensionality. The International Journal of Aviation Psychology, 

6, 241-71.

ENDNOTES

1

Subsequently, in 1987, the FAA Administrator approved 

the definition of the term “runway incursion” as “any occurrence at an airport involving an aircraft, vehicle, person, or 

object on the ground that creates a collision hazard or results 

in loss of separation with an aircraft taking off, intending 

to take off, landing, or intending to land.” This definition 

was clarified in 1996 to refer only to airports with operating control towers (Order 7050.1 2002). Consequently, 

runway incursions should not include “events involving 

aircraft, vehicles, pedestrians, or objects on the runway 

without permission when there is no collision hazard or loss 

of separation, nor should they include incidents involving 

animals. Although these and other similar unauthorized or 

unapproved movements occur on the airport surface, they 

are surface incidents, not runway incursions.”

2

 Source: Letter of recommendation dated July 6, 2000, to 

the FAA addressing runway incursions.

3

 FAA Order 7110M Air Traffic Control, 3-7-2. TAXI AND 

GROUND MOVEMENT OPERATIONS was current at 

the time of the evaluation. “Issue, as required or requested, 

the route for the aircraft/vehicle to follow on the movement 

area in concise and easy to understand terms. When a taxi 

clearance to a runway is issued to an aircraft, confirm the 

aircraft has the correct runway assignment. “

4

 All Office of Aerospace Medicine technical reports are 

available in full-text from the Civil Aerospace Medical 

Institute’s publication Web site: http://www/cami.jccb.gov/

aam-400A/Abstracts/Tech_Rep.htm.