Glass Cockpit  1999  

www.flightsafety.it  

Glass Cockpit 

Speaking of automation today makes little sense and certainly not useful, considering the great amount of conclusive literature on the argument. Experts, scientists and researchers, very often indeed, publish their thoughts and comments on the relation between the man and the machine he invents, carefully highlighting the ensuing advantages or disadvantages if improper use is made of it. Since many and not so late serious disasters, not only in aviation, were caused mainly by man-machine interaction, superficially attributed to human error, further considerations should gather thought about this conclusion and in particular the human performance aspect. One example is the serious problem represented by the great number of pilots that today, greater numbers tomorrow, find themselves having to change from the so-called conventional aircraft to technologically advanced glass cockpit ones. Most company fleets have aircraft that use different technological approach and

presentation of the flight data. It is often easy to see operating within a company, aircraft with either the so-called traditional cockpit or a fully glass one. In some cases aircraft can include both technologies, which constitute a hybrid piloting solution. Airline companies keep on buying new sophisticated aircraft as soon as the manufacturers make them available, because of the economical advantages they offer. Economy based not only on fuel consumption, as always a heavy item in the balance sheet, but also on other cost-efficient elements, such as the training of pilots. About twenty years ago in fact, four months of ground course were required to study an aircraft similar to the Boeing 707. Today, thanks to the advanced automation, a pilot completes the transition (rating) on a Boeing 777 in only ten days. That is quite advantageous indeed. At first sight then, the advantages are definitely undisputed. Unfortunately, the recent years' air accidents have shown, in all its seriousness that the savings enjoyed on the pilots training have been paid more dearly. Disasters such as the Thai Airways A 310 in Kathmandu in Nepal, or the China Airlines A300 at Nagoya or even the American Airlines B757 in Calì, having caused between them the death of hundreds of people, show how easy it is to lose awareness on an automated aircraft. Expert and trained pilots, familiar with the surrounding environment, made macroscopic errors, to the point of mistaking by 180 ° the desired heading, flying unknowingly into their death.

Glass Cockpit  1999  

www.flightsafety.it  

These reasons are enough to lay reasonable doubts. These doubts suggest that what has to date been said and done on matters pertaining the training automation is still not enough. Forcibly, other ways must be explored. It is often said that in 70-75% of air accidents the most probable cause is due to human factor. This data is definitely wrong: in fact it is 100%. Let us stop and think on who designs airplanes, on who designs the cockpit, who decides the tracks to be flown, on the environment, on company culture, etc. The answer is always the same: a human being. That is reason why you can't always refer to the pilot the human factor cause, only because he is the last link of the chain before the incident/accident takes place. The whole process that governs his decision to that point is effectively human factor yes, but not restricted to him only. How can a pilot change into a completely new mental model, often opposite to the one accustomed to, in about fifteen days? Piloting glass cockpit aircraft entails learning a new philosophy of flying. The new philosophy requires the transition from flying in an "active" way to flying in a "passive" way. An active way of flying requires a continuous control of hundreds of parameters that help to determine the choices necessary to the continuation of the flight. A passive way of flying requires the programming and the supervision of completely automated systems where the ever-advancing technology determines, on its own, most of the necessary choices. While a conventional airplane pilot decides for an action and acts on the controls following the formula pilot controls aircraft on the Glass Cockpit he controls that the action previously programmed, or however desired, is properly executed by the aircraft according to the formula pilot cdu fms controller autopilot control system aircraft. More of a monitor and vigilance task rather than a proper action task. On a conventional aircraft, the answer to an action being carried out is immediate, visible and clearly noticeable. In a glass cockpit aircraft things are not the same. When leveling the climb on a conventional aircraft, the technique suggests reducing the vertical speed to pre-established values and gently stops the climb at the desired altitude. Pilots rely on the airspeed indicator and the altimeter for maintaining and constantly checking the maintenance of an altitude. On a glass cockpit aircraft, the climb phase changes into a capture phase by using a conventional symbology. The cruise phase follows. The autoflight system informs the pilot, through the FMA, about the ongoing operation modes. The pilot therefore does not have vertical airspeed and altimeter references, but only the progress of the various autoflight system modes. This abstract from an ASRS (Air Safety Report System) needs no further comment: “ We missed the crossing altitude by 1000 feet. The captain was… busy trying to program the FMC. Being new in an automated cockpit, I find that pilots are spending too much time playing with the computer at critical times rather than flying the aircraft.” Not everything is "visible" and under control at all times, as we can see. In a glass cockpit aircraft, a switch positioned on its "ON" position activates systems the pilot had no idea of their existence. In addition, some improvements, such as the autotrim and better soundproofing, have resulted in making the perception of aircraft movement in space even more difficult. It has become imperative to control, through a continuous man-machine-man language, that the aircraft "executes" exactly what is requested. Pilots can no longer count on their sensorial perception and this has raised new needs for what concerns their training.

Glass Cockpit  1999  

www.flightsafety.it  

They must be trained to a new and more comprehensive concept of crew communication and situational awareness. Knowledge automation, monitor and vigilance, situation awareness, mode awareness, boredom, complacency, over-reliance, abuse of automation, distrust, automation intimidation, automation design, crew communication, decision making, are some of the issues that should supply the foundation on which a training program must be built. Unfortunately, programs are drawn from old, obsolete schemes put in act for conventional aircraft though with some variants, such as the need to know, nice to know concept. We keep on studying systems, its failures and the procedures to put them right. Nothing or little is said about the relation that develops between autothrust, autopilot and FMS, and what are the different levels of automation that the system is capable of supplying in function of one or more components' failure. The same could be said for programming difficulties, or the wrong use of automation, such as the programming of a continuous change of a landing runway during the approach phase using the FMS. In the whole loop, an important role is held by the maintenance engineering from which maximum onboard systems maintenance efficiency is expected. The maintenance technicians as well must be trained in acquiring a new mental model. Allowing for a certain period the autothrottle of a conventional aircraft to remain inoperative is not applicable in a glass cockpit one. In fact, in the latter, the autothrottle is a flight operations' fundamental element. It is true that the glass cockpit has allowed the reduction of the training period for what concerns the need to know. It is also true that it has introduced the requirement to acquire a different behavioral mental approach. Since no satisfactory training process has been suggested to achieve this, only adequate experience on the aircraft can help overcome, not solve, the problems arising from this new piloting mental model. In the glass cockpit, some of the pilot's skills, acquired through experience, are suddenly challenged by a third entity, apparently docile and controllable, but with unexpected and dangerous implications: the advanced automation. Flying with a glass cockpit means having the conviction that the controls, the buttons, levers, selectors are program activators, processing switches. It means understanding, without the shadow of a doubt, the cockpit architecture, simple in its display, but with hidden complicated engineering solutions, hundreds of subsystems. These subsystems obey to intelligence unknown to pilots and unwritten in their flight manuals. It also means to have faith in a computer, admittedly sophisticated, that is able to detect and diagnose a failure and suggest the appropriate actions for their remedy. With the advent of electronics, aviation has reached fantastic and, not so long ago, unthinkable levels of automation. The two-axis autopilot, hardly able to maintain two simple parameters, has given way to completely autonomous systems. The Dc-9 autothrottle, for example, almost never used "because it did not work properly", or the speed command, whose indications had to be in any case compared with the airspeed, indicator, they have all been put aside by systems capable of harmonizing the various and complicated requirements of an aircraft in motion.

Glass Cockpit  1999  

www.flightsafety.it  

Automation has allowed to draw flight profiles in which the aircraft protects itself from exceeding fundamental readings linked to the pitch angle, low and high airspeed, excessive bank angles. Autothrottle and autopilot integration, together with the flight management system, have allowed the development of an autoflight system capable of carrying out a complete instrument procedure. It can do this by changing the altitude when required, turning at the right moment, applying the correct approach speed corrections with the changing of the configuration. Navigation, once exclusive competence of the navigator, subsequently integrated with the pilot's tasks, today is perfectly handled by the FMS. The data, necessary to carry out an efficient and economic navigation, are precisely, automatically and constantly elaborated by automatic systems, which are preset to meet operating costs. A conventional aircraft pilot, on the other hand, has to fight with the meteorological, performance and navigation data, which distract him from flying the aircraft properly to the detriment of the flight economy. His calculations, however hard he tries, remains approximate. The periodic check of the systems operation, the concentration required in certain phases of the flight, the difficulty and the elapsed time necessary to detect a system malfunction, have given way to electronic surveillance systems, systems capable of diagnosing parts of a failing system and suggest the corrective actions. Information given by systems entirely dedicated to anti-collision surveillance against terrain and aircraft, such as the EGPWS, (Enhanced Ground Proximity Warning System) and TCAS (traffic Collision and Avoidance System) allow safe operations within high-density traffic areas. Reflection echoes provided by the weather radar, integrated in the navigation display and with systems, such as the WSAS (Wind Shear Advisory System), allow an immediate evaluation of the meteorological situation along the route and the possibility of anticipating and avoiding dangererous phenomena such as the wind shear. However, if on one side these systems do help the pilot, on the other side, especially in conditions of stress and fatigue, they run the risk of causing the pilot to fall into a state of confusion and disorientation. This state is a predisposition to an incident/accident. The CRM (Crew Resource Management) becomes an inseparable element of the glass cockpit training and should be a permanent and constant presence in a transition. It must not remain an isolated item in the educational process of a new flight philosophy. The pilot must be helped in the learning as he discovers the automation's functional intelligence. The man-machine-man communication, a correct decision making process, correct application of SOP, awareness confidence, are as important parts as the description of a system and its failures. Incidents occurred in glass cockpit aircraft should be analyzed and become integral part of a transition course as to allow the viewing of wrongful behaviors and help the pilot in identifying them. Pilots should have simulator sessions added to the normal ones as to maintain those skills necessary when the system degrades. System failures should be presented with the "cluster criterion" which helps in maintaining an adequate level of knowledge. Therefore, there is a lot to do in terms of engineering, training and education. Many solutions are in their embryonic state and surely, the glass cockpit represents a starting point towards a cockpit that could finally be able to show the navigation in a tri-dimensional display. In a tri-dimensional display, the aircraft is "visible" in respect of the surrounding environment that means adding the vertical profile to the lateral one. "The Captain then said, ' What's going on?' at which the aircraft was observed 300 feet high; it had entered a subtle climb seemingly on its own accord… This is another case of learning to type 80 words a minute instead of flying the aircraft. The more automation there is in the aircraft, it just means the flightcrew should work that much harder to remain an active and integral part of the loop".