Runway I ncursion Ladies and Gentleman, I am very pleased to make a - - PDF document

Runway I ncursion

Ladies and Gentleman, I am very pleased to make a presentation regarding ‘Human Factors in Runway Incursion’. As we know, ‘runway incursion’ is one of the important issues in aviation safety. For the past accidents and incident investigations, FAA and FSF has come to a conclusion that runway incursion is one of the leading factors deteriorating aviation safety. Air traffic controllers, pilots and drivers working in ramp areas can make a runway incursion. One of the well-known runway incursions is what happened several years ago in Chicago airport that Air China taxied back into the active runway after a Korean Air started rolling for take off on the runway. This kind of runway incursion is rare, but it is very critical issues. Runway incursion may be made by ATC. Several months ago Asiana Airline made a go-around in Los Angeles airport, because another aircraft was waiting for take off clearance on that runway. I think the agenda SE 46, 46 mostly concerns runway incursion induced by air traffic controllers. So I’d like to suggest that we just focus on the runway incursion in the perspectives of air traffic controller. And I expect that we can get some practical ideas about designing air traffic controller training program and air traffic management procedures. My point is that we should understand runway incursion by air traffic controllers in the context of air traffic controllers working conditions and

• environments. As we agreed that most of this kind of runway-incursion is

Human-Factor related issues. To understand Human-Factor related situation awareness, we have to understand ‘information processing theory’. I will give you short briefing regarding ‘Information Processing Theory’ (Wickens & Carswell, 1997). This theory explains how human beings think and act. And it is fully consistent with ‘situation awareness’ (Endsley,1995; Figure 1), which is critical determinants of pilots’ and air traffic controllers’ performances.

[Figure 1] Information Processing Theory, Wickens and Carswell If a person receives a stimulus by sensory organs such as eye, nose, ear, then he/she decides if it is important/interesting or not. The only stimulus he/she thinks important or interesting draws his/her attention(Situation Awareness Level 1) and is interpreted (Situation Awareness Level 2) what it means based

• n long-term memory (which is developed by training and experience) and

short-term memory/working memory (which is impossible to be developed by training). Let’s take an example. If you see some one passing by you, then it does not draw your attention unless he/she is very attractive. You see him/her passing (Situation Awareness Level 1) but it means nothing. But if you see one of your best friends crying (Situation Awareness Level 1), then it is something. You know something wrong with your friend (Situation Awareness Level 2). How do you know that your friend has problem. You know it from your experience. If you see one aircraft landing nice and smooth (Situation Awareness Level 1), it does not draw your attention. But if you see smokes on the runway (Situation Awareness Level 1), it is something (Situation Awareness Level 2).

Then one collects all the information available and thinks what’s going on

• there. This process is based on the long-term and short-term/working memory.

If you see smokes and fire on the engines during take off and it persist for a while (Situation Awareness Level 1), then you may think there is fire on the engine (Situation Awareness Level 2). How do you come to a conclusion? Yes, it comes from the long-term memory (knowledge learned in the class and experience) and short-term/working memory (The aircraft just took off). After considering all the information, then one may have a big picture what’s going

• n (Situation Awareness Level 2) and what would come in the future (Situation

Awareness Level 3). Now you can decide what to do to solve the problems. He/she will inform the pilot of the fire (Situation Awareness Level 3). How does the air traffic controller make such decision? It also comes from the long-term memory (knowledge he/she learned in the class and operation procedure) and short- term memory (The aircraft just took off and it is critical for the safety). These are all ‘Situation Awareness’. If one is well trained, then one perceives stimulus easily (Situation Awareness Level 1), has no difficulties in understanding what’s going on (Situation Awareness Level 2), identifies the problems precisely (Situation Awareness Level 2) and solves the problem logically (Situation Awareness Level 3). This is what we call ‘Situation Awareness’, which is determined by the long-term and short-term/working memory. Now, we know that air traffic controller performance is limited by long-term and short- term/working memory. This is the reason why we emphasize on training (long- term memory) and situation awareness (short-term/working memory). Now, let’s get further into ‘long-term and short-term/working memory’. The long-term memory is built by training and experience. Remember when you first took lessons on the air traffic management. You probably did not know anything about air traffic management. How do you become an experienced air traffic management? You studied a lot. You read and read again. You memorized all the important things again and again. We have to try again and again until you understand what they are and how they organized. As a consequence, you can manage the air traffic control without studying air traffic management procedures whenever you manage air traffic. All the information for air traffic management is in your mind. The long-term memory is efficient if it logically and structurally organized.

Let’s assume that you try to find a book regarding old Chinese book in the

• library. If library clerk do not classify book logically, it is almost impossible to

find book just in 5 minutes. But if he/she classify book in organized manner such as Literature/ China, Japan, Korea and US / 17C, 18C, 19C and 20C/ Author, then anyone can find book easily if he/she knows the author and the publishing year and country. This is why we emphasis on the training program and effective teaching and learning method. But you may forget something, if you do not use it for a long time. We need review periodically to keep it in the long-term memory. That’s why we have recurrent training. Now, let’s look at the ‘short-term memory’. The short-term memory is active memory from the long-term memory just for a while and it is used for doing

• something. We may compare short-term (working) memory to RAM (Random

Access Memory) in computer. If your computer equipped with 128M, it functions, but not so fast. But sometimes it does not function because the program needs more RAM (it needs more working memory to do something). If you expand RAM up to 512M, then it works nice and smooth. On unfortunate thing is that

• ur short-term/working memory is so limited. We cannot expand our short-term

memory like we do RAM in the computer. One can normally remember 7 items at one time. If you try to remember 8 or 9 items, you probably miss one or two items, because it is beyond your ability. It is given by the God. You can NEVER EVER expand your short-term/working memory capacity by training, medicine

• r foods.

If the air traffic controllers have to do 4 items at the same time – issuing take

• ff clearance, monitoring take off aircraft, verifying runway is clear and issuing

landing clearance, they may be able to do so. But if the items air traffic controllers have to do exceed 8 items at the same time – in addition above 4 items, informing pilot of the engine fire, requesting change frequency to departure, informing emergency crews ready for emergency situation and answering traffic coming into tower frequency, then they may not be able to do all those items. They probably miss one or two items. So we can say air traffic controller performance may be affected the working memory. What if we train and expands air traffic controller’s working memory? Once again, it’s impossible, because it is determined by the God. That is the reason we make a standard procedure and reduce workload as much as possible. Just keep your air traffic controller’s workload within human being’s capability/acceptable level.

One more thing! One can not maintain short-term/working memory active unless you repeat it again and again. Let’s assume that you try to dial unfamiliar phone number. You have to repeat again and again to dial correctly. That’s why we emphasis on the scanning procedure. And if you greet to your friend while you are dialing, then you probably fail to dial correct numbers. This is ‘distraction’. So we have to keep air traffic controller focus on the current

• status. This is the reason we emphasis on the discipline.

Let’s imagine that you cleared one aircraft for take off (short-term/working memory) and are about to issue a landing clearance to a landing aircraft (short- term/working memory). At that time, if a supervisor ask controller if he/she could have lunch (new stimulus, distraction, not disciplined act), then you probably forget to issue a landing clearance or ask departing traffic to contact departure control (Lapse). Most of his/her attention will be drawn to supervisor (distraction), so that you may miss something (distraction, Lapse). That’s why we stress ‘air traffic controller CRM training and discipline’. As for CRM, it is vital to understand what others’ doing and appropriate communication procedure among the members. It’s is too complicated. So I do not mention it here. If you want, I will do it later. Now we may be able to say that air traffic controller induced runway incursion depends on training program (long-term memory) and environment conditions such as radar facility (short-tem/working memory), traffic volumes ( workload, short-tem/working memory), runway and taxiway layouts - one runway/ two runways/ parallel/ converging or corssing and if the ATC clearly see the runway condition or not- and working condition - duty hours; fatigue and environment (workload, short-tem/working memory) and so on (discipline). And it varies from country to country, from airport to airport. Once again, I fully agree that the traffic volume in this region will be increased drastically in the near future and runway incursion will be the one of important issues in the future. I am not sure if air traffic controller working conditions and airport environment (short-term/working memory) in this region is same with those of US or Europe in terms of air traffic volume, runway and taxi way layout.

So that I’d like to suggest as follows. First, let the human factor expert identify factors generally affecting air traffic controller’s short-term/working memory. This information will be essential to design air traffic controller training program and operation procedures. Second, let the State evaluate and anticipate air traffic controller’s workload if it is or will be a potential risks. Finally, let the human factor expert develop programs or procedures to maintain appropriate levels of situational awareness for the air traffic controllers to be prepared for the high traffic volumes. Thank you. Reference

• 1. Wickens, C.D. & Carswell, C.M.(1997). Information Processing. In G.

Salvendy(ed.), Handbook of human factors and ergonomics (2nd ed.). New York: Wiley

• 2. Endsley, M.R.(1995). Towards a theory of situation awareness in dynamic
• systems. Human Factors, 37(1).