Development of a computer simulator for air traffic controllers

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КАЗАХСКИЙ НАЦИОНАЛЬНЫЙ УНИВЕРСИТЕТ ИМ.АЛЬ-ФАРАБИ

МЕХАНИКО-МАТЕМАТИЧЕСКИЙ ФАКУЛЬТЕТ

Кафедра информационных систем

Information systems

Development of a computer simulator for air traffic controllers

Алматы, 2016

Content

Introduction

1. Statement

1.1 Applicability

1.2 Practicability

1.3 Technical methods of supporting

2. Statistical analysis of airplane accidents

2.1 Growth in air traffic

2.2 Drop in aircraft accident rates

2.3 Scheduled passenger flights are less likely to be involved in accidents than other types of flights

2.4 When do accidents occur?

2.5 Root causes of accidents

3. Dispatcher action scripts for various, emergency situations

3.1 Icing of flight

3.2 Strom front

3.3 Cabin pressurization

3.4 Oncoming traffic

3.5 Crossing airways

4. Practical implementation of the interface training program

Conclusion

Literatures

Introduction

Airports - the most important part of the public transport infrastructure, air gateway of each country. Every year growing the flow of tourists, so the increasing demand for air transportation, increase airport capacity, improving the quality of passenger service. So nowadays we need a lot of qualified flight dispatchers and also increasing the number of vacations to this responsibility, because most of them go to retirement .To produce qualified flight dispatchers we need special technical tools and programs. Aflight dispatcherassists in planningflight paths, taking into account wind direction and destination or alter airports, and other conditions. Dispatchers provide a flight following service and advise pilots if conditions or paths change. They usually work in the operations or control, weather, storms, aircraft performance and loading, landing condition center of the airline.

Purpose: Our goal is to create an imitation model of this dispatching training program and provide them the cheapest way to learn all features. Dispatcher is to be ready for a variety of emergency situations : the speed of its response, optimal actions in assisting the crew of the distressed aircraft and just methods that the controller uses to staff work of all funds in high traffic density depends on its fitness. It is not always the situation may develop in accordance with the provided technology works dispatcher options. To simulate the catastrophic situations in the air without using modern imaging systems, it is impossible. Modern panoramic fitness equipment, trainers taxiing operations, trainer dispatchers working with images of planes on interface. It's approach of aircrafts circle, make it possible to simulate all weather conditions, any air conditions and any abnormal situations in the air. From the banal to capture engine incidents in aircrafts to entry terrorists to the aircraft and acceptance by all parties of non-standard solutions, and on the ground, rolling out from unauthorized equipment on the runway to all kinds of ground equipment failures.

1. Statement

When people think about air travel, most think that when they fly they are in the hands of their pilot. While this is true, a flight crew cannot fly without the help of a team of people on the ground. An aircraft dispatcher makes airline operations work and ensures that both pilots and their passengers are able to travel safely to their destination .Flight plans ,safety guidelines, and weather patterns are all part of the work performed by a dispatcher ,but many wonder what exactly a flight dispatcher does while on the job.

A job as a flight dispatcher or aviation scheduler involves a lot of pressure. Airlines could not function efficiently without highly skilled people on the ground, ensuring aircraft are where they need to be. A vital part of airport life is the task of keeping the airplanes operating on schedule - the individuals who take responsibility for this are know as flight dispatchers or aviation schedulers. In airport operations, the airline captain and the dispatcher are held jointly responsible for the safety of the flight. Working with the pilot, the flight dispatcher furnishes a flight plan that enables the aircraft to arrive at its destination on schedule with the least operating cost. The flight dispatcher must take into account the weather - both during the journey and at the final destination.

That means studying winds aloft, thinking about alternative destinations, fuel requirements, altitudes, and general traffic flow. The dispatcher's signature, along with that of the pilot, releases the aircraft for flight. In this role he is the go-between for the pilot and ground service personnel, and keeps all personnel concerned with the flight informed about its status. It's also important for the dispatcher to fully understand navigation facilities, airline routes and landing characteristics of all aircraft operated by the airline. The flight dispatcher sometimes rides in the cockpit with the flight crew while the plane is taxiing to observe flight routes, conditions, and airports. Flight dispatchers frequently work under pressure in a fast-paced environment especially when flying weather is bad.

They must make many rapid decisions concerning safety, flight regulations, and the economy of operations . These employees are surrounded by people, teletype machines, telephones, and intercom systems in a noisy, busy atmosphere. Those who work for a small airline, carry on the duties of a meteorologist and schedule coordinator. The importance of the flight dispatcher or aviation scheduler should not be underestimated. He shares 50/50 decision making and responsibility for the safety of each flight with the airline captain. Flight dispatchers tend to work indoors at the airport in the airline operations office or control center. They use computer software systems, calculators, weather charts and information, and loading re-ports. A 40-hour week with shift work is normal.

Flight and aircraft dispatchers' day-to-day duties include:

· Performing the pre-flight duties as the cabin crew prepare for the flight

· Providing the pilot with the advised route for an individual flight

· Assessing weather reports and informing the pilot of any hazards

· Making checks on aircraft maintenance issues

· Reviewing aircraft weight, fuel loads and cargo loads

· General duties to ensure the aircraft is safe and ready to fly

· Reporting to air traffic control and airport staff about departure times, and after departure, providing reports on aircraft status and predicted arrival times.

Finally, its need a lot experience in trainer equipment and programs .It involves a lot of pressure, as you are essentially the lead communicator regarding a flight's activities. Its need to have excellent communication skills, a high attention to detail, strong judgement and a willingness to work flexible hours to get the most out of this rewarding career.

1.1 Applicability

To teach dispatchers we need a lot of equipment, programs that cost more expensive and we shouldn't need to buy a lot of programs by foreign IT companies. Uniquely structured in a highly-effective desktop programs and using new generation aircraft, airline dispatch students train in conjunction with flight crew, and maintenance training programs, allowing students to build upon a deeper knowledge base .Such kind of desktop applications will be on each computer and to release this programs not so hard and expensive.

1.2 Practicability

Our application will contain such kind of situations and these situations also important for each flight dispatcher:

Ш Use of communication systems and the appropriate normal and emergency procedures.

Ш Meteorology, including various types of meteorological information and forecasts, interpretation of weather data (including forecasting of enroute and terminal weather conditions), frontal systems, wind condition, and use of actual and prognostic weather charts for various altitudes.

Ш Prevailing weather phenomena and the available sources of weather information, making an accurate and operationally acceptable weather analysis from a series of daily weather maps and of weather condition prevailing in general neighborhood of a specific air route and to forecast weather trends pertinent to air transportation with particular reference to designated terminals.

Ш Navigational aids, publications, principles of air navigation with particular reference to instrument flight operations.

Ш Characteristics of appropriate airports.

Ш Air traffic control, instrument approach procedures relevant to the duties of a flight dispatcher and determining optimal flight path.

Ш Rules and regulations relevant to air transportation.

Ш Use and limitation of altimeters, particularly in respect to barometric settings.

Ш Techniques for maintaining a flight watch.

Ш Procedures for communicating with aircraft and relevant ground stations.

Ш Providing operating supervision and all other assistance to flight in adverse conditions appropriate to the duties of the flight.

Ш Basic principles of computer based flight planning.

Ш Operational procedures for the carriage of freight and dangerous goods.

Ш Procedure relating to unlawful interference and sabotage of aircraft.

Ш Knowledge and skills in Human Performance of Flight Dispatcher.

1.3 Technical methods of supporting

To provide good training program also we need add Digital Data Communication Systems and Voice Communication Systems. Also we need computers and video cameras to our training application.

Dispatchers use such kind of equipment and in our training courses we haven't this one that contain also audio files that control our diction when dispatcher give instructions to pilots .It would be also true pronunciation phrases or false .In practical implementation we use dictionary of words that is the diction is true or false. While

Dispatcher will be training his diction and the meaning of words.

It's the real equipment that use dispatchers in their work -Aeronautical Telecommunications (Volumes I, II, III, IV and V) Three of the most complex and essential elements of international civil aviation are aeronautical communications, navigation and surveillance.

It is divided into five volumes:

Volume I -- Radio Navigation Aids

Volume II -- Communications Procedures including those with PANS status

Volume III -- Communication Systems

Part 1 -- Digital Data Communication Systems

Part 2 -- Voice Communication Systems

Volume IV -- Surveillance Radar and Collision Avoidance Systems Volume V -- Aeronautical Radio Frequency Spectrum Utilization

2. Statistical analysis of airplane accidents

Aircraft accident statistics can prove a valuable source of information that allows for the setting of priorities and the monitoring of progress made by the aeronautic industry. They are being calculated for many kinds of aircraft. The statistics presented in this section include worldwide commercial jet planes with a maximum gross weight of over 60,000 pounds. Airplanes manufactured in the former Soviet Union (CIS) are not included.

2.1 Growth in air traffic

Air traffic increased exponentially between the beginnings of aviation and 2001. After the attack on the World Trade Center, however, many airlines came into financial difficulties and air traffic started to drop. Two years down the line, traffic picked up again.

Figure 1 Air traffic growth

In 2013, airplanes clocked a record 54.9 million flight hours. It is important to keep this number in mind when interpreting statistics and failure rates: it means that, although an event may have only a 1 in a million probability of happening, it will, statistically, occur several times a year.

The following graph shows the total number of certified commercial jet airplanes with a maximum gross weight of over 60,000 pounds. It does not include airplanes manufactured in the former Soviet Union.

Figure-2 Evolution of the number or aircraft in operation

The number or aircraft in operation keeps increasing, in a bid to meet growing transport demand. Fortunately, despite congested airspaces, collision risk remains very low thanks to new technologies that provide accurate position and altitude measurements, a definite help to both crews and Air Traffic Controllers in preventing collisions. For example, in order to accommodate all traffic over some oceans, specific airspaces where aircraft are separated vertically by only 1000 ft were created. These are called 'RVSM' (Reduced Vertical Separation Minima) airspaces.

The graph above shows that the average flight time also increases with time. Some state-of-the-art aircraft can perform22-hour non-stop flights and fly halfway round the world without landing. These very long-haul aircraft are becoming ever more common.



Figure-3 Average flight time increase

2.2 Drop in aircraft accident rates

Although the number of accidents per flight has been decreasing with time, the number of fatalities per year has been variable, without dropping.

Figure-4 Evolution of the number of accidents and fatalities

Aircraft accidents are less likely to occur today than 20 years ago. Nevertheless, the growing number of aircraft in operation and their increasing capacity cannot result in a reduction of onboard fatalities.

Table - 1 (*)External fatalities include on-ground fatalities as well as fatalities on other aircraft involved.

	1959-2013	2004-2013
Number of accidents	1 859	407
Number of onboard fatalities	29 368	3 848
Number of external fatalities (*)	1 198	138

2.3 Scheduled passenger flights are less likely to be involved in accidents than other types of flights

As journalists like to remind us, you are less likely to be involved in an accident when flying a regular flight than when taking other types of flights (unscheduled passenger and charter, cargo, ferry, test, training, and demonstration flights). The same conclusion can be drawn from the following graph:

Figure-5 Scheduled passenger operations and other kind of operations

The above graph also shows that scheduled passenger operations are 5 to 6 times more common than other types of operations.

2.4 When do accidents occur?

Between the time a passenger boards an airplane and the time they disembark, there are 6 distinct phases:

· Taxi: the aircraft taxis to reach the runway, or it taxis to the gate after landing.

· Take off and initial climb: the aircraft accelerates, lifts off and starts climbing.

· Climb: the pilot retracts the slats/flaps, and the aircraft climbs until it reaches cruise altitude.

· Cruise: the aircraft flies at a more or less constant altitude. This is generally the longest phase of the flight.

· Descent and initial approach: the aircraft descends to get closer to its destination airport. Air traffic control may request the aircraft to loiter and wait its turn for the next phase.

· Final approach and landing: the aircraft, in landing configuration and aligned with the runway axis, approaches the runway threshold, then lands and slows down.

Figure-6

When do accidents occur?

Almost half of all accidents occurs during the final approach and landing stages. These are also the most devastating accidents.

Fatal accidents are also likely to occur during the climbing stage. If the aircraft left the gate with undetected faults, these may become apparent during the climb, as the first stage taking place off the ground, and could prove dangerous. If the crew believe the failure requires the aircraft to land as soon as possible, they will decide to perform an IFTB (In-Flight Turn Back). This could turn out to be difficult, however, as the aircraft is flying low and may have already lost some of its capabilities.

Most accidents and fatalities take place during the departure (take off / climb) and arrival (approach/ landing) stages. During these phases aircraft are close to the ground and in a more vulnerable configuration than during other flight phases: the crew have to deal with a high workload and reduced manoeuver margins.

2.5 Root causes of accidents

It is quite rare for an accident to be explained by one single cause. Almost every mishap is the consequence of a chain of events and accident reports usually discriminate between the main cause and a number of contributing factors. The following graph shows the distribution of main causes identified in plane crashes.

Figure-7 Root causes of plane accidents

The main root cause is human error. In order to try and eliminate this as a source of accidents, crews are requested to follow a strict training routine. Next come aircraft failures, but these are less likely when it comes to modern aircraft.

3. Dispatcher action scripts for various, emergency situations

3.1 Icing of flight

Icing is among aviation's most serious weather hazards because it renders aircraft unflyable before flight and severely reduces aircraft performance within flight. Icing causes mission delays during ground deicing of aircraft and mission cancellations and abortions because of forecast or actual in-flight icing. This report assesses the effects of icing, both before and during flight, on the ability of Flights to accomplish their mission.

How does ice build up on airplanes? Ice builds up on aircraft in two ways: in flight or on the ground. On the ground, precipitation falls onto the airplane and freezes on upper surfaces much like what happens if you leave your car out overnight. On planes, ground icing forms on the upper surfaces of the wing and tail. That type of ice is managed by de-icing the plane with a fluid [typically propylene glycol] at the airport. In flight icing is where the airplane is flying through clouds made up of small liquid water droplets. These liquid water droplets can be sustained as liquid below the freezing point. Everybody knows that 32 degrees Fahrenheit (0 degree Celsius) is where water freezes. It turns out that if the water is very pure--if it is condensed out of the atmosphere--and there is nothing for that water to freeze on, it can be sustained below the normal freezing point.

What we find in the wintertime is clouds that are made up of small water droplets where the water temperature can be as low as negative 40 degrees C. Here comes this plane flying through the cloud, and the water droplets impact the airplane and then freeze because now they have a surface to freeze on. Ice builds up in flight on the frontal surfaces: leading edge of the wings, the nose and the tail surfaces. There are systems to prevent ice or to remove ice. The de-icing system works on the basis of allowing ice to form before being broken off [using pneumatic boots that inflate to crack the ice]. The anti-icing system prevents ice from forming by blowing hot air from within the compressor of the engine. We can recreate icing conditions on a model.

Why is ice a problem for airplanes? Ice reshapes the surface of the lift-producing parts of the airplane: the wings and the tail. That roughness is enough to change the aerodynamics of the wing such that there's more drag and less lift.

The amount of lift a wing creates depends on the relative angle that the airstream has to the airfoil. As you increase that angle--the angle of attack--you generate more and more lift. But at some point air cannot flow over upper surface, and you have aerodynamic stall. The point at which aerodynamic stall takes place has to do with the contour of the airfoil. If the surface is contaminated with slight roughness--sandpaper roughness-it will reduce the lift and change the point at which stall takes place.

For scheduled air carriers [including commercial passenger airlines] icing has been a contributing factor in 9.5 percent of fatal air carrier accidents.

How are pilots trained to handle aerodynamic stall? As you go through pilot training--without icing involved--you practice wing stalls. You bring the nose up and the airplane shakes around because of separated flow. To recover from that, you push the nose down to reduce the angle of attack on the wing and recover. What happens with ice is same principle, but it is happening at a lower angle of attack.

Why would having a plane on autopilot interfere with a pilot's ability to prevent stall? If a person is hand-flying an airplane and the airplane has a reversible control system, then for every action the pilot makes on the control there is some reaction on the control. There is the ability for the airplane to talk to you.

When the autopilot is engaged, that information isn't being passed onto the pilot. The National Transportation Safety Board recommends against flying with autopilot under icing conditions. Companies make their own choices on how to present that information to the pilot.

Task of dispatcher is to:

- Indicate nearly airport to land on;

3.2 Strom front

Bad weather

Any pilot worth his or her wings will do their best to avert potentially hazardous weather pockets, but it does happen. Especially athigh altitudes, ice and tumultuous weather conditions can create dangerous situations. Pilots need to ask permission to scale to higher heights in order to avoid a storm, which can come bearing lightning - able to strike an aircraft - and microbursts - strong wind currents that can throw an aircraft for a loop. Intense precipitation can "drown an engine," and a barrage of hail can break through the windshield of the cockpit. Ice can cause malfunctions to measuring equipment, which are crucial for pilots to be able to determine speed and direction. Moreover, inclement weather can prompt a pilot to use assistive instruments to see, which can be less accurate and therefore cause error.

Running out of fuel

We all know how to fill our gas tanks - pop open the nozzle, stick the hose down the pipe, squeeze, yap on your cell phone, start the engine, etc. etc. So what could be so hard when it comes to reading and topping off a fuel tank on a plane? Well, for one, the fuel gauge might be malfunctioning. This was so forAir Canada flight 143, whose fuel meter was broken. Crew members had to do the fuel quantity calculations by hand, but forgot to convert metric units to standard ones - so the plane ran out of fuel way too early. Fuel leaks caused by malfunctioning equipment can also rob an aircraft of its energy source. In an attempt to avoid dangers in the air, planes can also run out of precious resources while dithering. Planes, of course, do glide (ten kilometers out for every one down), though this is not ideal.

Birds strikes

There are more than airplane wings in the sky. Birds can get sucked up into jet engines, causing them to malfunction completely, disturb pilot visibility, or just become an obstacle. There were over 10,000bird strikeson a civil aircraft in 2012 alone. You can't account for the migration of geese in your pre-flight schematics because birds don't listen to reason. They just fly. A flock of birds took down US Airways Flight 1549, causing it to make an astounding emergency landing in the Hudson River. Unfortunately, the large open spaces presented by airports are very attractive to birds seeking food, water, and shelter. To keep the airways safe from the pests, air traffic control has tried "harassment strategies" like pyrotechnics and noisemakers, as well as making the airport environment uninhabitable for non-human travelers.

Task of dispatcher is to:

- Indicate nearly airport to land on;

3.3 Cabin pressurization

Cabin pressurizationis a process in which conditioned air is pumped into thecabinof an aircraft orspacecraft, in order to create a safe and comfortable environment for passengers and crew flying at high altitudes. For aircraft, this air is usually bled of from thetas turbine engine sat the compressor stage, and for spacecraft, it is carried in high-pressure, oftencryogenictanks. The air is cooled, humidified, and mixed with recirculated air if necessary, before it is distributed to the cabin by one or more environmental control systems. The cabin pressure is regulated by the outflow valve.

Rapid and explosive decompression are serious concerns. This is when the cabin loses pressure at an alarming rate and can have serious repercussions.

These emergencies are real attention getters. Pilots will physically feel a “kick in the chest” as their lungs adjust to the change in pressure. Cabin temperature will instantly drop well below freezing while moisture in the air condenses to form a thick fog within the airplane. Amid these distractions, the pilot's number one priority is to retain consciousness by donning an oxygen mask, then to initiate an emergency descent. Not knowing the cause of depressurization, it's a good idea to assume the worst: structural failure. It may be tempting to dive down at maximum speed, but any increase in airspeed will increase stress on the airframe. Commercial operators train their pilots in procedures for cabin depressurization. From a pilot's perspective, it is as simple as following a mental checklist, backed up by the appropriate emergency checklist at a later time.

Task of dispatcher is to:

- Indicate nearly airport to land on;

3.4 Oncoming traffic

Situation an "oncoming traffic" arises up, when two aircrafts follow on one corridor, but in meeting directions (fig. 8)

Figure 8

In instance where crew of one of such Aircraft pilot asks the set of height, and other - a decline and calculation interval of longitudinal echelonment less than than settled (fig. 1, а) in the moment of divergence of aircrafts, the task of dispatcher consists in:

- determination of mean value of height (between the current echelons of the first and second aircrafts);

- informing of crews both aircrafts about a mutual location and conclusion both aircrafts on contiguous echelons near by value to the expected medium-altitude (fig. 1, б);

- after divergence of aircrafts on a safe interval - permission of continguos set and decline (fig. 1, в).

3.5 Crossing airways

In cases where the aircrafts coming to the point of intersection of air routes (routes) at the same level and on the calculation of a safe range of longitudinal separation is not provided, it is necessary to apply the vertical separation by setting one of the conflicting aircrafts to new level .

Based on practical experience, it is not recommended to ask the crew to climb, the possibility of a set of high-level limited by the weight of the sun and the engine speed, and the crew is not able to guarantee the specified speed dial tier dispatcher. It is much more effective will be the aircraft declines.

The most important condition to ensure safety during this five-ne conflict is the speed controller action. Aircraft converge at a high speed, and therefore must be quickly defined, casting the conflict, to develop an algorithm of actions by the Armed Forces breeding and put it into action. It must be remembered that this type of conflict is the most insidious, and in such circumstances occurred much aircrafts collisions in the air

Task of dispatcher is to:

- Inform both crews on the mutual location;

- Change of flight level one of the aircrafts;

- Control the sun divergence on safe intervals;

- The return of the sun to its previous level (if necessary).

To sum up I want to say that we will provide all of these situations in our imitation model as parameters and also in the end of this situation training program will be contain exercises .

4. Practical implementation of the interface training program

WPF technology with c# programming language

The Windows Presentation Foundation (WPF) is a graphical display system for Windows. WPF is designed for .NET, influenced by modern display technologies such as HTML and Flash, and hardware-accelerated. It's also the most radical change to hit Windows user interfaces since Windows 95.

Programming implementation of training system.

This is an interface of training program that the red circles are aircrafts in air and its flying in the space:

Figure-9

These are the screenshots of training program: MainWindow.xaml.cs



Figure-10

Figure-11

It is MainWindow.xaml section of program:



Figure-12

airplane accident interface dispatcher

Conclusion

Air travel safety is definitely a data-driven activity. Although the number of aircraft in operation is constantly on the rise, accident rates are falling, making air transport the safest of all means of transportation. Improvements bear fruit, and the usefulness of aircraft monitoring and redundancies can be witnessed everyday.

The increase in flight length also contributes to explain the drop in the number of plane crashes. Since accidents mainly occur during the take-off and landing phases, a long-haul aircraft performing only one or two long cycles a day is indeed less likely to be involved in an accident than a short-range aircraft performing in the region of ten short cycles a day.

Finally, the introduction of regulations and of checks by authorities and the growing experience of aircraft manufacturers all contribute to the safety of air transport.

However, what with a growing number of aircraft now operating, even though the rate of accidents per flight may drop slightly, the actual number of accidents will increase. Since aircraft carry an ever increasing number of people, the number of onboard fatalities will per force rise too.

A comprehensive survey is in the center of the project. This includes duties as well as interfaces and tools. Training requirements of program have been determined corresponding to the job profile which has been established in the survey. The survey results indicate operational control personnel have an important role in achieving the goal of safe and efficient operation, but should be thoroughly trained according to dispatcher training program. The outline of a suitable training program is presented and its market chances are analyzed. The industry has recognized the need for adequate training of operational control staff as many dispatchers have increasing difficulties in hiring competent individuals. Nevertheless, the lack of regulatory requirements for a formal basic dispatcher's training makes it difficult for training providers to fill their courses to a level which is required to make the product financially viable.

Literatures

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2. Обслуживание воздушного движения: Прил. 11 к Конвенции о международной гражданской авиации. - Монреаль: ICAO, 2001.

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6. Правила и фразеология радиообмена на английском языке при выполнении полетов и управлении воздушным движением в воздушном пространстве Российской Федерации : метод. пособие / Министерство транспорта РФ; ГС ГА; под ред. Е.Н. Королева. - 2-е изд. - М. : ГС ГА, 2001.

7. Типовые Технологии работы диспетчеров органов обслуживания воздушного движения (управления полетами) при аэронавигационном обслуживании пользователей воздушного пространства РФ: утв. Приказом Росаэронавигации от 14.11.2007 № 108.

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