Air Traffic Control Communication

Table of contents

Universität Flensburg

1. Introduction

2. The History of Air Traffic Control

3. What is Air Traffic Control (ATC)?

4. Air Traffic Control Communication
4.1. Technology in Air traffic Communication
4.2. Phonetic Alphabets used in Air Traffic Communication
4.3. The ‘Q’ Code

5. Conclusion

References

1. Introduction

In this modern day and age it has become very important being able to travel from one country to another in a very short time by airplane. Transporting all kinds of cargo across the world without great time loss has become a essential part of our everyday life. Or how would you feel if you weren’t able to buy your bananas and mangos in the supermarket in your hometown anymore?

Millions of people travel every day and thousands of containers have to be flown, to guarantee the full supply of all consumers in the world. The extreme increase of air traffic over the years has made it necessary to introduce rules for air traffic controlling, develop new technology and establish standards that are valid for everyone. A major part of air traffic control is the communication (ATCC) and the technology involved in it. It is necessary in the entire world to regulate all sorts of communication between ground controllers and the pilots of aircraft. But why was this communication invented? How is it used? And are there special forms of air traffic control communication?

All these questions and an overview of the technological inventions, that are used nowadays in air traffic control, will be given in the following chapters.

2. The History of Air Traffic Control

When the Montgolfier brothers invented their first untethered human hot air balloon in 1783, nobody would have thought that aviation would develope into what it is today.

In the beginning only few aircraft were travelling throughout the air and no communication was needed. But when the traffic of aircraft increased, people soon noticed, that a ground-based control was necessary to regulate the takeoff and landing of all aircraft. Especially in Europe, where aircraft were often flown from one country into another, it soon became apparent, that some kind of standard rules were needed to prevent aircrafts from getting into danger.

In 1919, the International Commission for Air Navigation (ICAN) was created to develop ‘General Rules for Air Traffic.’ Its rules and procedures were applied in most countries where aircraft operated.

(http://www.centennialofflight.gov/essay/Government_Role/Air_traffic_control/POL15.htm, retrieved March 17th, 2008)

These rules were only used in Europe, as the United States of America did not sign the Convention of the ICAN.

In 1926 the USA passed the Air Commerce Act which allowed the the Department of Commerce to establish air traffic rules for the navigation, protection, and identification of aircraft, including rules as to safe altitudes of flight and rules for the prevention of collisions between vessels and aircraft. These first rules were more like a form of advice rather then strict orders that had to be followed. For example, pilots were discouraged to begin their takeoff until there is no risk of collision with landing aircraft and until preceding aircraft are clear of the field.

(http://www.centennialofflight.gov/essay/Government_Role/Air_traffic_control/POL15.htm, retrieved March 17th, 2008)

In the beginning these forms of advice worked well and helped to regulate the air traffic. But as the air traffic increased rapidly, the airport operators soon came to the conclusion, that these advices alone, would no longer fulfill the need of the progression of aviation. The number of colliding aircraft put a form of pressure on the operators to quickly find a solution.

A first form of air traffic control (ATC) was invented, which based on visual signals. These signals were given by controllers that were on the airfield. By waving flags they communicated with the pilots and gave them orders on when to take off or how to navigate on the field.

(http://www.centennialofflight.gov/essay/Government_Role/Air_traffic_control/POL15.htm, retrieved March 17th, 2008)

As new technolgy was developed in the area of radio communication, all aircraft and airport control towers were equipped with the needed devices. The flagmen on the airfield were mostly replaced during this progress, as they were no longer necessary.

The Cleveland Municipal Airport tower was the first one to operate with radio communication in 1930. Only two years later, in 1932, all aircraft had been radio-telephone equipped and in 1935 already 20 airport towers were operating with radio communication only.

(http://www.centennialofflight.gov/essay/Government_Role/Air_traffic_control/POL15.htm, retrieved March 17th, 2008)

The radio communication solved the problems on the airports but the increasing air traffic in airspace, caused an additional problem. Between certain cities there was a very high frequency of air traffic and the airspace beyond the airfield needed to be regulated too.

Cleveland, Chicago and Newark belonged to the cities with the highest take off and landing contingent. In 1935 the airports of these cities decided on coordinating the traffic in the airspace on the routes between them together. At the end of that year the first Airway Traffic Control Center opened at Newark, New Jersey. Chicago and Cleveland opened centers in the year following.

(http://www.centennialofflight.gov/essay/Government_Role/Air_traffic_control/POL15.htm, retrieved March 17th, 2008)

As technology wasn’t as far on as it is today, the first route controllers had to use maps and blackboards to track the positions of the planes.

In addition, telephones were used to stay in contact with airline dispatchers and airway radio operators. These dispatchers and operators functioned as intermediaries between the controllers and the pilots of the planes. They were responsible for transmitting information between the ground and the aircraft.

Air traffic control soon became a governmental task. In July 1936 the first appropriation of $ 175,000 USD was granted and the government started to provide air traffic control. The local authorities where the towers were located, vested their own agents to continue to operate the facilities.

(http://www.centennialofflight.gov/essay/Government_Role/Air_traffic_control/POL15.htm, retrieved March 17th, 2008)

In 1941 the US government decided on assigning the Civil Aeronautics Administration (CAA) with the task of air traffic regulation. The government appropriated a large sum of money for the CAA to construct new towers and to take over old ones. At almost all airports ATC became a permanent federal responsibility. The CAA also invested in expanding the route air traffic control system to provide greater safety in airspace.

After the second world war air traffic control was completely revolutionized by introducing radar. Radar uses radio waves to detect distant objects and meant a great new advantage in air traffic controlling as the controllers were now able to “see” the position of an aircraft on a specially invented video display.

By 1952 all towers for ATC had been radar equipped and personnel was trained to use it for all approaching and departing flights. Long-range radars were installed only for years later and allowed a constant monitoring of all aircraft in flight.

(http://www.centennialofflight.gov/essay/Government_Role/Air_traffic_control/POL15.htm, retrieved March 17th, 2008)

Over the years new innovations were introduced to ATC, like airway communication stations. that were very similar to today’s flight service stations or transponders, that were built into all aircraft and that identified it and helped to improve radar perfomance. Laws were passed that forced pilots to fly on instruments regardless of the weather and to always stay in contact with controllers. These new developments made it possible for the controllers to reduce the separation between aircraft passing oneanother and that lead to greater safety in flight.

Over the years the Federal Aviation Administration (FAA) took over a major part of the air traffic controlling tasks. Installing new innovations and modernizing the whole air traffic control system, was and still is one of their most important tasks.

The FAA started in July 1988 with developing and builing in a new Advanced Automation System (AAS) into every control tower. This new system included new computer hardware and software and brought the air traffic control system to higher levels of automation.

It still took 6 years until the concept of the Free Flight was introduced, which ment that onboard instruments and electronic devices could be used by the pilots to maintain a safe distance between planes.This made it possible to reduce their reliance on ground controllers. Since then, the concept of the Free Flight has been improved by numerous inventions, like advanced aircraft transponders, a global navigation satellite system, and ultra-precise radar.

Travelling has developed, over many years from hot air ballons to zeppelins to huge aircrafts for hundreds of passangers.

Saftey is almost guaranteed nowadays and the development of new and more efficient aircrafts is irresistable.This progress has made transatlantic travelling by airplane possible. This option was a great step forward for society, especially from the economic point of view, but it also brought new problems along. Pilots from Europe and other countries were not always able to speak English and communicating with the controllers, sometimes seemed impossible. Misunderstandings and horrible accidents were the result. A solution had to be found quickly.

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