Analysis of Aircraft Accident Investigations - Case Study Example

ANSP Incidents/Accidents Investigations Insert Name Tutor Date Introduction The main responsibility of air traffic controllers is to ensure safe and orderly flow of air traffic in their own air space as well as the neighboring airspaces. This responsibility must never be based on the controller’s personal views on attempting to control multiple aircraft, getting involved in multiple tasks and receiving information from multiple sources. These factors may sometimes mount a lot of pressure on the air traffic controller and may forget his or her responsibility (HES6601 Module 2, p5) leading to accidents or incidents as discussed in this report. Some of the errors that contribute to accidents in the air traffic control include loss of situational awareness and improper communication. These two have also been associated with the incidents discussed in this report. Situational awareness is described in HES6601 (Module 2, p34-35) as the ability of a person to understand his or her physical environment. It is refers to how a person understands their dynamic environment. It involves continuously extracting information from the environment, then combining this information with the previous knowledge to create a mental picture that one uses to anticipate the future (HES6601 Module 2, p34-35). Effective situational awareness requires one to have the three levels of awareness. These are perception, integration/comprehension and projection. Perception is impacted by a person’s prior knowledge and experience (HES6601 Module 2, p37). Comprehension/integration is the ability to combine, interpret, store and remember information. Projection involves understanding the dynamics of the environment. That is the ability to determine how the future may differ from the present (HES6601 Module 2, p39). Loss of situational awareness in these three levels may lead to aircraft accidents. Communication involves that ability of the air traffic controllers to communicate their instructions with the aircraft. Poor communication is associated with some of the worst aircraft accidents in the world including the two that have been discussed in this report. However, for communication to be effective, it must be two way. It involves transmission of the correct information and receiving the same (HES6601 Module 2, p78). This report looks at investigation reports by the Australian Transport Bureau on two aircraft accidents where the accidents were caused by loss of situational awareness and poor communication. The report also looks at what can be done to minimize human errors in air traffic control. Incident 1 Investigation Number AO-2010-035: Incorrect aircraft configuration - Airbus A321-231, VH-VWW, Singapore Changi International Airport, 27 May 2010 This incident occurred on 27th May 2010, at 1422 Singapore time an Airbus A321-231 aircraft (A320), registered VH-VWW and operating as Jetstar flight JQ57, departed from Darwin Airport scheduled to land at Changi international airport in Singapore. At about 1840, the aircraft was at the top of descent when the Singapore Air Traffic Control directed an approach clearance towards the North to avoid thunderstorm that was occurring to the eastern and western side of the air port (ATSB, 2010, p1). A series of step-down descent clearances and instructions were issues so that the speed of the aircraft can be reduced to enable management of traffic separation and arrivals. The main incidence was improper configuration even as the aircraft was 500 feet above the aerodrome. However, the first office had received a message Electronic Centralized Aircraft Monitor (ECAM) which was displayed on the warnings display but he thought that the message was due to his failure to push the Side stick takeover button twice. The first office just requested the captain to clear the message because he found it distracting his attention (ATSB, 2010, p2). The crew therefore ended up in a missed approach due to wrong configuration and his reported failure to observe stable approach criteria. Analysis of the incident report According to the investigation report, there was distraction of the crew due to many ongoing activities. One of the distracting issues was the request by the air traffic controller requiring slowing of the aircraft earlier than the crew had expected. The other distracter was the receipt of the message and then the detection of the ECAM alert. The distraction caused by all these affected their situational awareness to an extent that they failed to notice incorrect configuration (ATSB, 2010, p8). Communication breakdown can also be evidenced by failure of the crew to give attention to the text message and the ECAM alert. The proper information was communicated but was not received properly. This can be seen as breakdown in crew resource management. Affective crew resource management could have ensured that situation awareness is maintained and the landing approach could have been completed according to the standard operating procedures (ATSB, 2010, p7). Improper monitoring by the captain was also identified in this investigation. This is why the non standard disconnection of autopilot by the first officer and the ECAM alert were not detected until when the aircraft was near the approach. This failure was also said to be contributed by the distraction caused by the text messages (ATSB, 2010, p7-8). According to this report, there was lack of commitment to safety by the captain who stated that after the crew completed planning for the flight in Darwin, he received a phone call from the airline’s operations group as he proceeded to the aircraft. The phone call was to inform him of the weather changes in Singapore and that he needed to have more fuel. After the call, the captain did not turn the phone off even as they departed (ATSB, 2010, p6). Some of the safety factors that were identified to have contributed to the incident include lack of proper monitoring of the aircraft’s configuration by the captain, the various distractions identified above that led to loss of situational awareness and failure by the crew to detect a problem in the aircraft configuration, lack of proper communication among the crew members and poor decision making by the first officer (ATSB, 2010, p9). Incident 2. Investigation Number: AO-2011-011 Breakdown of separation - Boeing B737, VH-VBK and Israel Aircraft Industries Westwind 1124, VH-AJG, 22 km South of Williamtown (Newcastle Airport), NSW, 1 February 2011 This incident occurred at 1305:25 Easter Daylight-saving time on 1st February 201. This was a breakdown of separation that occurred 22km South of Williamtown at the Newcastle air port located in New South Wales. The breakdown was between Boeing B737-7Q8 (737), registered VH-VBK, and an Israel Aircraft Industries Ltd Westwind 1124 (WW24) aircraft, registered VH-AJG (ATSB, 2011, p1). At 1300:33the controller at the Williamtown Aerodrome coordinated instruction for the departure of B 737 with the lower approach controller. The requirements in these instructions were for the B737 to climb up to 5000 ft in a left turn so that it can intercept its outbound track. However the local air traffic control procedures required that B737 should be transferred direct from the Williamtown Aerodrome Controller to the higher approach frequency after it has departed since it was to be departure level of 5000 ft or more(ATSB, 2011, p2). At 1300:53, crew operating WW24 contacted the higher approach controller as they were 59.3 km south of Williamtown and passing 10,800 ft on descent. They were requesting for a visual approach since they were visual with the air port and on 9,000 ft descent. The higher approach controller advised them to descend on 5000 ft visual and they will be later advised on the type of approach (ATSB, 2011, p2). The main cause of this incident was loss of separation assurance. The local air traffic control procedures required that the standard assignable level that was to be issued to the descending aircraft by the Approach High (APP (H)) was 6,000 ft. however, the approaching aircraft WW24 was also issued with the same level as the departing aircraft B737 and there was no separation standard between them. The result was loss of separation assurance between the two aircraft since B 737 was on Aerodrome controller frequency while WW24 was on the high approach frequency (ATSB, 2011, p1). Analysis of the incident According to the investigation report, various errors by the air traffic controllers, both the high approach controller and the low approach controller contributed to this incident. One of the errors occurred due to wrong advice given by the high approach controller to the WW24 pilot where they were advised to take a descent of 5000 ft. At this time, the aerodrome controller and the low approach controller had already coordinated the departure instructions for B737. The two aircraft therefore ended up being assigned similar descent level hence the conflict (ATSB, 2011, p8). Poor coordination and communication are other problems that could be associated with this incident. The low approach controller had put in place a plan for maintaining radar difference between 737 and WW24, with the two being maintained at different controls. The low approach control however was late in tracking the WW24 for left base and so the aircraft tracked direct to the airport. The low approach controller’s intention was that the direct track could have allowed separation between the two aircraft. However, the low approach controller did not communicate his plan to the high approach controller who considered that if this was left to happen, the aircraft could have collided. The high approach controller therefore tried to avoid the conflict by vectoring 737 and this instead worsened the situation (ATSB, 2011, p9). The local air traffic control procedures that existed in the department of defence are not clear in that they did not clearly outline the responsibilities and requirements during the coordination for both the low and high approach coordinators for a departing aircraft (ATSB, 2011, p9). Safety factors that contributed to the incident Some of the safety factors that were identified to have resulted in this incident include: i. The descent assigned by the high approach controller WW24 led to loss of separation assurance. ii. The two aircraft were meant to de on different controls and to have different frequencies when operating the low approach designated airspace and also at the same altitude. iii. Failure by the low approach controller to verbally communicate the planned separation changes to the high approach controller. iv. The air traffic controllers from the department of defence had not been trained on how to apply separation recovery techniques in compromised situations. Some procedures that can solve the problems identified in the above incidents Air traffic control involves a complex interaction between the controllers, the systems they operate as well as the tasks they perform. This complex environment leads the many errors that occur in air traffic control that result to various accidents and incidents. However, to ensure safety in this complex environment, there is need for technological advancement in the way things are carried out in their traffic control. Proper management of human factors is also very important in air traffic control because many of the errors that occur are due to poor coordination between the humans involved in the navigation services (Eurocontrol, 2007, p15). Some of the problems that were identified in the two incidents include poor communication and coordination, loss of situational awareness, fatigue among the pilots. However, some of these problems arise due to the complex environment of the air navigation services. Below are some of the procedures that can be followed to mitigate some of these problems: Automation Automation is defined as the replacement of functions that were previously performed by humans to be performed by a system (HES6601, Module 3, p11). With the complex environment in air traffic control, automation can help in minimizing errors and improving safety in the aircraft operations (HES6601, Module 3, p11). There is a lot of information use in air traffic management which may not be easily comprehended by the air traffic controllers. Such information includes maps of where the aircraft are flying through, data tags and other procedural information among others. This amount of information in most cases leads to loss of situational awareness resulting to aircraft accidents (Baumeister, Estkowski, Spence, &Clothier, 2009, p2). For example in the incident of incorrect configuration of Airbus A321-231, automation can be applied in changing the configuration. This could be applied where there can be automatic change of configuration where the systems indicate a configuration problem. Figure 1below is an example of automated airspace architecture. Figure 1. An example of automated airspace architecture. Adopted from Erzberger, H., (2001), page 3. Above is a typical system that can be used to offer a cost effective and secure protection against loss of separation which may be due to errors by aircraft controllers or critical component failure. The main element in the design is the Tactical Separation Assisted Flight Environment (TSAFE) which together with the Automated Airspace Computer System (AACS) and the controller interface offers the functions that are required for the operation of the automation concept. TSAFE has various components that are required for airspace control. It is made up of trajectory tracking error module, conflict detection section and conflict avoidance advisories (Erzberger, 2001, p4). Technological changes To improve safety in air traffic control, technological changes needs to be made in the complex environment of air traffic management to prevent errors that results to accidents and incidents. Technological changes that can help in minimizing errors in air traffic control include of Automatic Dependent Surveillance Broadcast (ADS-B), User Preferred Routes (UPR) and User Preferred Trajectories (UPT) among others (HES6601 (Module 1, p31 ). Automatic Dependent Surveillance Broadcast (ADS-B) is technique that can be used to monitor aircraft instead of using the surveillance radar. ADS-B uses global Positioning System to give a report on the exact position of the aircraft. It is a technique that involves equipping the aircraft with the ADS-B transponder that keeps broadcasting aircraft data. The air traffic controllers will therefore receive similar information from all aircraft which they will use to determine the exact position of aircraft. ADS-B can provide all the information without the need for radar installation or even ground station transmissions (Reddy, 2010, pp4). Under this technique, the aircraft will transmit information on its current position, its speed, and the direction in which it is travelling through a digital link twice per second. One of the advantages of this technology is that the system can also be used by ground vehicles which are present at the airport to report on where they are located on the airport tarmac. This information can therefore be integrated in the Airport Movement Area Safety System (Reddy, 2010, pp6). User Preferred Routes (UPR) is another technological technique that can be used to ensure safety and efficiency in air traffic control. This technique has been used in South Pacific oceanic airspace for several years. This concept means airlines can choose to fly through optimized routes that will enable them to achieve efficiency during the flight due to prevailing benefits such as the patterns of the wind instead of flying through the fixed routes. The user preferred route however requires use of air traffic control systems that will be able to support aircraft that choose to operate outside that fixed airways. Once the route has been defined based on the forecast on wind direction and temperature, it is then digitally uplinked into the aircraft flight management computer. This technology can be used to avoid aircraft conflict because aircraft fly over independent routes and do not cross any common points as it happens with fixed routes (Air New Zealand, 2011, pp 2&3). User Preferred Trajectories (UPT) is another technology that involves operating in either constrained or unconstrained air traffic management environment. Unconstrained ATM environment is defined as where an aircraft operator can operate his aircraft in a manner that achieve his own targets for a particular flight without interferences from presence of other aircraft, procedures of constraints from the air traffic controllers. A constrained air traffic management environment is a real life complex environment. Operators may therefore choose to operate in the unconstrained environment to enable them in achieving their own targets such as reduction in the operational costs and low fuel consumption (Eurocontrol, 2004, p3). Promoting a safety culture in Air Traffic Management Safety is a core value in air traffic management. In ATM, safety culture aims at ensuring that it is observed in all the air traffic management organizations and that it is kept at the forefront in the minds of people in air traffic management in whatever role they play. Maintaining the safety culture in the entire organization will ensure that small problems that may arise and lead to major accidents can be noticed and stopped before they become major issues (Columbia Accident Investigation Board, 2003, p 182). Figure 2 below shows the components of Safety culture.  Figure 2. Components of a Safety culture. Adopted from Skylibrary (2010), retrieved from http://www.skybrary.aero/index.php/SMS_in_Air_Traffic_Management Safety culture involves various aspects. These include reporting culture, just culture, flexible culture and learning culture. Reporting culture encourages all the employees to disclose any information concerning safety hazards that they may come across in the organization. Just culture promotes accountability for acts against ATM rules and encourages the employees to disclose information through rewarding disclosure of information related to safety. Flexible culture ensures effective adaptation to the changing work demands especially in the complex environment of air traffic management. Learning culture ensures that people respond to safety indicators and hazards that are continuously revealed through audits, internal assessment and incident analysis (Eurocontrol, 2008, p13). Effectiveness of the recommended remedial actions Regarding the first incident, the Australian Transport Safety Bureau (ATSB) recommended that in addressing the safety issues raised, the organization should initiate a practical safety action instead of just issuing safety recommendations (ATSB, 2010, p9). This action can work because the actions that led to the incident were because of failure to observe a safety culture by the crew. the action plan will involve taking the entire air navigation team through the all the procedures that may create a safety culture. These include a proper understanding of what is safety culture, assessing a safety culture and how to enhance safety culture (Eurocontrol, 2008, p17). Working under a safe culture means that communication is handled safely and that there is no likelihood of loss of situational awareness (Reason, 1998, p102). Regarding the second incident, the Australian Transport Safety Bureau (ATSB) recommended that the air traffic controllers in the Department of Defense should be trained on techniques for compromised separation recovery (ATSB, 2011, p11). These techniques enable the controllers to give priority to issuing alerts to the pilots when they realize that the aircraft are in unsafe proximity. This includes use of words such as Traffic Alert, Turn Left/Right, Climb or Descend. However, this training may not be adequate to mitigate the safety problem identified since the main problem was in communication and coordination. Proper communication is part of a safety culture which if well observed, it would solve the problem. However, for issues of coordination, automation can also be effective. Conclusion The investigation reports by the Australian Transport Safety Bureau (ATSB) have identified errors in air traffic management as the main cause of accidents/incidents. Loss of situational awareness and poor communication has been associated with the incidents discussed in this paper. The outcome of these incidents indicates that there is need for the air navigation service providers to design plans to deal with these errors. Some of the ways that can work in minimizing these errors include proper training of the air traffic controllers and the crew teams and also enough emphasis on promotion of safety culture in the air navigation service providers. However, if humans will always remain subject to errors, it is important for organizations to consider use of technological means that have been discussed in minimizing the errors. Bibliography Eurocontrol, (2008), Safety Culture in Air Traffic Management: A White Paper, European Organization for the Safety of Air Navigation, City of Brussels. ATSB, (2010), Incorrect aircraft configuration - Airbus A321-231, VH-VWW, Singapore Changi International Airport, 27 May 2010. Retrieved from http://www.atsb.gov.au/publications/investigation_reports/2010/aair/ao-2010-035.aspx ATSB, (2011), Breakdown of separation 22 km South of Williamtown (Newcastle Airport), NSW, 1 February 2011, retrieved from http://www.atsb.gov.au/publications/investigation_reports/2011/aair/ao-2011-011.aspx Erzberger,H., (2001), The Automated Airspace Concept, NASA Ames Research Center Moffett Field, CA. Eurocontrol, (2004), Control of Users Preferred Trajectories in a constrained ATM Environment, Technical specification, European Organization for the Safety of Air Navigation, City of Brussels. Baumeister, R, Estkowski, R, Spence, G, and Clothier, R., (2009), Test architecture for prototyping automated dynamic airspace control. In: Council of European Aerospace Societies 2009 European Air and Space Conference, 26-29 October 2009, Manchester Central Exchange Hall, Manchester. HES6601 (Module 1), Human Factors in Air Traffic Management, Air Traffic Control: The Big Picture. Swinburne University of Technology. HES6601 (Module 3), Human Factors in Air Traffic Management, Air Navigation Service Provider Organizations, Swinburne University of Technology. HES6601 (Module 2), Human Factors in Air Traffic Management, The Air Traffic Controller, Swinburne University of Technology. Reddy, A., (2010), The Science and Technology of air traffic control, retrieved on 14th May 2012 from http://arstechnica.com/science/2010/03/the-science-and-technology-of-air-traffic-control/4/ Air New Zealand, (2011), User Preferred Routes, retrieved on 14th May 2012 from http://www.airways.co.nz/aspire/_content/user_routes.asp Eurocontrol, (2007), Conflict Detection, European Organization for the Safety of Air Navigation, City of Brussels. Reason, J. (1998), Achieving a safe culture: The practice. Work & Stress, 12(3), 293-306. Columbia Accident Investigation Board lead by Harold W. Gehman (2003), Report of Columbia Accident Investigation Board, Volume I. Available from http://www.nasa.gov/columbia/home/CAIB_Vol1.html Skylibrary, (2010), SMS in Air Traffic Management, retrieved on 15th May 2012 from http://www.skybrary.aero/index.php/SMS_in_Air_Traffic_Management Read More

Improper monitoring by the captain was also identified in this investigation. This is why the non standard disconnection of autopilot by the first officer and the ECAM alert were not detected until when the aircraft was near the approach. This failure was also said to be contributed by the distraction caused by the text messages (ATSB, 2010, p7-8). According to this report, there was lack of commitment to safety by the captain who stated that after the crew completed planning for the flight in Darwin, he received a phone call from the airline’s operations group as he proceeded to the aircraft.

The phone call was to inform him of the weather changes in Singapore and that he needed to have more fuel. After the call, the captain did not turn the phone off even as they departed (ATSB, 2010, p6). Some of the safety factors that were identified to have contributed to the incident include lack of proper monitoring of the aircraft’s configuration by the captain, the various distractions identified above that led to loss of situational awareness and failure by the crew to detect a problem in the aircraft configuration, lack of proper communication among the crew members and poor decision making by the first officer (ATSB, 2010, p9).

Incident 2. Investigation Number: AO-2011-011 Breakdown of separation - Boeing B737, VH-VBK and Israel Aircraft Industries Westwind 1124, VH-AJG, 22 km South of Williamtown (Newcastle Airport), NSW, 1 February 2011 This incident occurred at 1305:25 Easter Daylight-saving time on 1st February 201. This was a breakdown of separation that occurred 22km South of Williamtown at the Newcastle air port located in New South Wales. The breakdown was between Boeing B737-7Q8 (737), registered VH-VBK, and an Israel Aircraft Industries Ltd Westwind 1124 (WW24) aircraft, registered VH-AJG (ATSB, 2011, p1).

At 1300:33the controller at the Williamtown Aerodrome coordinated instruction for the departure of B 737 with the lower approach controller. The requirements in these instructions were for the B737 to climb up to 5000 ft in a left turn so that it can intercept its outbound track. However the local air traffic control procedures required that B737 should be transferred direct from the Williamtown Aerodrome Controller to the higher approach frequency after it has departed since it was to be departure level of 5000 ft or more(ATSB, 2011, p2).

At 1300:53, crew operating WW24 contacted the higher approach controller as they were 59.3 km south of Williamtown and passing 10,800 ft on descent. They were requesting for a visual approach since they were visual with the air port and on 9,000 ft descent. The higher approach controller advised them to descend on 5000 ft visual and they will be later advised on the type of approach (ATSB, 2011, p2). The main cause of this incident was loss of separation assurance. The local air traffic control procedures required that the standard assignable level that was to be issued to the descending aircraft by the Approach High (APP (H)) was 6,000 ft.

however, the approaching aircraft WW24 was also issued with the same level as the departing aircraft B737 and there was no separation standard between them. The result was loss of separation assurance between the two aircraft since B 737 was on Aerodrome controller frequency while WW24 was on the high approach frequency (ATSB, 2011, p1). Analysis of the incident According to the investigation report, various errors by the air traffic controllers, both the high approach controller and the low approach controller contributed to this incident.

One of the errors occurred due to wrong advice given by the high approach controller to the WW24 pilot where they were advised to take a descent of 5000 ft. At this time, the aerodrome controller and the low approach controller had already coordinated the departure instructions for B737. The two aircraft therefore ended up being assigned similar descent level hence the conflict (ATSB, 2011, p8). Poor coordination and communication are other problems that could be associated with this incident.

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