ATCpaperBerndtsson.pdf

Coordination in Air Traffic Control Work

The Copenhagen Fieldstudies

Johan Berndtsson

berndtsson@cti.dtu.dk

Maria Normark

normark@cti.dtu.dk

Center for Tele-Information

Technical University of Denmark

Table of Contents

INTRODUCTION .......................................................................................................................................... 1

R ESEARCH M ETHODS ................................................................................................................................... 2

THE ORGANIZATIONAL CONTEXT....................................................................................................... 3

ROLES AND STAFFING .............................................................................................................................. 4

WORK ARRANGEMENTS IN COPENHAGEN ATC.............................................................................. 5

T HE A PRON T OWER ...................................................................................................................................... 6

T HE T OWER .................................................................................................................................................. 7

T HE A PPROACH ............................................................................................................................................ 8

T HE A REA C ONTROL C ENTER ( EN ROUTE CONTROL ) .................................................................................. 10

TOOLS AND PROCEDURES..................................................................................................................... 11

THE COMPUTER SYSTEM ...................................................................................................................... 12

T HE F LIGHT P LAN L IFE ............................................................................................................................... 13

THE FLIGHT STRIPS IN THE STRIP RACK ........................................................................................ 18

THE CLOSED-CIRCUIT TELEVISION-SYSTEM................................................................................. 22

THE FLIGHT STRIPS AND THE CLOSED-CIRCUIT TELEVISION SYSTEM............................... 24

T HE USEFULNESS OF THE FLIGHT STRIPS ..................................................................................................... 25

T HE COORDINATIVE FUNCTIONS OF THE STRIPS AND THE CLOSED - CIRCUIT TELEVISION SYSTEM ............... 28

C OORDINATION THROUGH THE USE OF STRIPS AND THE CLOSED - CIRCUIT TELEVISION SYSTEM ................. 31

CONCLUSIONS ........................................................................................................................................... 33

REFERENCES.............................................................................................................................................. 36

Introduction

As an air traffic controller it's your job to maintain safe and cost effective control of the

airspace - to make sure that the aircraft are separated at all time, and that they are given an

optimal route to keep cost and flying time at a minimum. Since most aircraft pass through

more than one sector, there is also a need to be aware of the colleagues work and

coordinating work with them. The ability e.g. to foresee what the situation in a specific

sector will look like in the next 5 minutes is of extreme importance to the controllers, and

can only be answered through suitable coordination between the actors involved.

Air traffic control work is a highly complex, distributed, and time-critical activity. In

Copenhagen some 260 controllers, assistants and supervisors are involved in the

controlling of aircraft in the Danish airspace. The controlling is being done from several

different locations, different ‘control rooms’, depending on where the aircraft is located.

Within and between these 'control rooms', controllers and assistants are working together

to make air traffic control safe and efficient. The time-critical aspect also makes for a large

difference between ATC work and for example accounting, or design work. If the designer

stops working for a few minutes her sketches will 'freeze', nothing will happen, but if the

controller will stop working for a few minutes the situation in the air will not freeze, but

continue to change. ATC work, as well as other time critical work, is thus 'paced' by this

continuos change (Schmidt, Forthcoming).

To overcome the difficulties descending from this geographical separation, and to

facilitate the coordination of actions, air traffic control work is heavily supported by

different procedures, each with it’s specific functions and areas of use. E.g. the division of

airspace into sectors allowing a division of responsibility between controllers, agreements

between sectors stating when and where certain activities will take place etc. The many

and highly specified procedures serve as a resource in that the controller always knows

e.g. where to expect a certain flight, what flight level (altitude) it will have etc. The

reliance on procedures gives the controller time to deal with unforeseen situations when

they arrive.

In many situations the work of the controllers is not only supported by procedures but

also by different artifacts. Some of these are aimed at enabling the controllers to be aware

of the current situation in the sky, such as the radar. Others are designed to reduce the time

it takes to perform specific tasks, such as the speed dial panel for the telephone on the

controller’s positions. However to cope with the distributed settings described above there

are also artifacts specifically designed to facilitate the coordination of the controllers’

activities in the different control rooms. An example of such an artifact used at

Copenhagen Airport is the flight plan database and it's printouts (the flight progress

strips), and the closed-circuit television system used to selectively display parts of

controllers workplace to other controllers.

In this paper we will report on some of the findings from an ethnographically inspired

field study focussing on coordination between different ‘control rooms’ conducted at the

Copenhagen Air Traffic Control Center in Denmark. We will describe the ways in which

the controllers work, and the use of three coordinative artifacts, a database, the flight

strips, and a closed-circuit television system. In relation to this we will discuss the diverse

conclusions of other research groups regarding the use of flight strips. Finally, we will

draw conclusions regarding what coordinative functions the use of these artifacts fulfill.

One of the goals of the COTCOS ATC research that has been discussed is the

possibility to compare settings and findings from different ATC centers in Europe. We

have therefore chosen to include a fairly rich description of the settings in this paper.

Research Methods

The results presented in this report are based on ethnographically inspired field studies,

primarily consisting of informal interviews and participatory observations. About 20

interviews have been conducted, with several different groups involved in air traffic

control work at Copenhagen Airport, e.g. controllers, supervisors, assistants, and

technicians. These interviews were recorded on audiotape. We have also had the

opportunity to talk to some Swedish en route controllers, from Malmö and Stockholm

ACC.

Informal interviewing was chosen mainly because it offers a significant benefit

compared to more structured interview techniques in that very few assumptions regarding

what is important in the work studied are made at an early stage.

The interviews were generally followed by participant observation sessions lasting

between one and three hours each. During a majority of the observation sessions the

informant has been asked to continuously tell the researchers what s/he is doing during

her/his actual work. Many of these initial observations have thus been conducted with a

high level of interaction between the researchers and the informants. In order to capture

some of the details of the work with these artifacts, we used video camera recordings for

several of our observations.

Most of our studies have been conducted in the Approach control. There are two major

reasons for this. First, we wanted to study coordination between geographically distributed

actors, in the approach the controllers are constantly coordinating their activities with the

adjacent sectors (be they Danish or Swedish), as well as the tower. Both are

geographically separated from the Approach control (see Figure 3), as opposed to studying

en route controlling between adjacent sectors where controllers are often positioned close

to each other. Second, the approach controllers handle a large amount of traffic within a

rather small volume of airspace. This fact increases the effects of the time critical aspects

of air traffic control work, and thus also the need for effective coordination.

To analyze the collected data we have indexed and written summaries of the interviews

and videotapes, and transcribed sections of central importance to our project.

Complementing questions from interviews and observations were handled through

repeated visits, but also through E-mail, fax and telephone communication with some of

the air traffic controllers.

In order to learn more about the direction in which the evolution of ATC technology is

heading we have also visited the Eurocontrol 1 test center in Bretigny to see a part of a

large simulation with Swedish and Danish controllers testing a version of the future ATC-

system. We have also read material about this new system. Our studies have also involved

studies of manuals, technical drawings and specifications, as well as academic books,

reports and papers. Much of the academic literature have been on air traffic control, such

as the work of Hopkin, Halverson (Halverson, 1995) 2 and the Lancaster CSCW group

(Hughes et al., 1988; Harper et al., 1989a) 3 , but there has also been a substantial body of

literature on relevant aspects from the field of CSCW (Computer Supported Cooperative

Work).

The Organizational Context

By focusing on the relations between the different organizations involved in the process of

producing air traffic we will in this section give an overview of the context in which air

traffic control work is embedded. Our purpose is to provide a background to the more

specific discussions regarding the coordination of air traffic control work presented in the

following chapters.

Air traffic control work is one of several activities involved in producing, or supporting

the production of, airborne transportation of people and goods between geographically

separated locations. There is an extensive network of organizations involved in the

production of flights and there is also an extensive amount of rules and regulations that

shape the activity. The organizations involved in the actual flying are the airway

companies, Eurocontrol 4 (the European organization for the safety of air navigation), the

Danish Civil Aviation Administration (Statens Luftfartsvæsen), and the airport. Each of

these three groups has different tasks to perform within this activity, as well as different

purposes and goals with their participation, but they share however the interests of

'producing' efficient air traffic.

An airway company, e.g. Scandinavian Airlines, British Airways etc., takes the first

step to ‘create’ a flight by writing a request for a specific flight. The request includes

information on where and when the flight is going to take place, as well as wishes

regarding how the flight is to be executed, what route, altitude etc. that the aircraft will

utilize on its journey. Once completed, the flight plan is submitted for inspection to

Eurocontrol's Central Flow Management Unit 5 (CFMU) in Brussels, Belgium. The flight

Eurocontrol is a European organization doing research and development to improve air traffic management in

Europe. Visit Eurocontrol on the WWW, http://www.eurocontrol.fr , or http://www.eurocontrol.be .

See also (Halverson et al., 1992; Halverson, 1994b; Halverson, 1994a).

See also (Harper et al., 1989b; Bentley et al., 1992; Hughes et al., 1992; Sommerville et al., 1992; Harper and

Hughes, 1993; Hughes et al., 1993; Harper et al., 1994; Hughes et al., 1994; Shapiro et al., 1994; Sommerville et

al., 1994).

Eurocontrol was 1960 for the purpose of overseeing upper airspace air traffic control for the member states. Today

Eurocontrol plays a central part in the development of new air traffic control systems in Europe. (Eurocontrol,

1998)

"The CFMU is responsible for providing ATFM services within the airspace of participating European States. Its

main objectives are to develop and maintain the highest level of quality service possible to both its Air Traffic

Plik z chomika:

Inne pliki z tego folderu:

Inne foldery tego chomika: