What’s flying? The plane at rest takes off, beating the force of gravity, it lifts with the forward thrust beating the air resistance, and it is air-borne and on to its flight destination. This looks very simple. To achieve this condition several safety systems, most of them automated and carefully watched and monitored by the staff on duty and the team of pilots, have to work in tandem and without the slightest fault. Then only the airplane will stay up in the air. Before trying to understand the latest safety systems in Aircraft Automation, it is necessary to know what actually is flying and what happens to it in the process. When a plane is flying, it is being pulled up and down, backward and forward—all at the same time. There are four different forces acting upon it at the same time. These are (i) weight (ii) lift (iii) thrust and (iv) drag. The weight is the force of gravity that pulls the plane downwards. Lift pushes the plane upward. This force is created by the wings as they cut through the air. The force of ‘drag’ pulls the plane backward, while ‘thrust’ pushes it forward. Thrust is produced by propellers. A plane remains steady in flight because of two important reasons. (i) The thrust from the engine equals the drag force; (ii) The lift made by its wings equals the force of gravity on the plane.
Aircrafts and automation:
Modern commercial aircraft is computer dominated. The Pilot has very limited manual functions, but this in anyway does not diminish his functional responsibility. On the contrary, his responsibility is more. He needs to be on the alert constantly and take appropriate measures on the basis of chart and data provided by the various automated safety systems installed in the airplanes. He may not have dull tasks of the good old days. Computers do computations and obtain data for the pilot. But he has to monitor the information on the pilot display and arrive at conclusions about the behavior of the airplane. The data must be to the point, with no unnecessary overloading of information. They must allow the pilot to anticipate correctly.
“Hybrid systems combine two types of behaviors: how a system evolves over time according to the laws of physics, and how the system evolves according to signals and switches. The combination of these two, referred to as continuous and discrete dynamics, leads to extremely complex behavior. In the case of the aircraft, this means that we can model how the aircraft flies as well as the logic which drives the aircraft automation. Hybrid systems are controlled through the combination of continuous and discrete signals we can directly alter.”(Oishi, Meeko)
Commercial aircrafts provide a very good example of hybrid systems. The automation is a complex system and the interaction of complex continuous dynamics needs to be studied seriously. The aircraft behaves like an errant child. When it holds a constant attitude, it behaves in one manner, but the behavior changes when it tries to climb and ascend. But nothing to worry, the aircraft automation systems are designed for such everyday operational eventualities. They have gone through the ultimate test and intense certification processes. But this is a costly process, and the hybrid process answers it with economy and equally brilliant performance. With the hybrid control, the airplane will behave like an obedient child, and it will never leave the safe place. . “The result is quite powerful — a complex system, subject to real-life errors and limitations, is mathematically guaranteed to be safe in the face of those errors and limitations.”(Oishi,Meeko)
All safety systems in an airplane are interlinked. You can’t have one safe system and another not-so safe system. Most of the functions are done thorough automation, like holding on to a constant altitude, the constant rate descent, smooth touchdown on the runway. Even though the main part is done through automation, pilot is actively involved in these processes. He is aware what he can expect from automation, his mental mode works with certainty, he is exactly aware of his position, and accurate data is made available to him in the cockpit interface. With these automation facilities, the pilot will not be taken by surprise in auto landings. The ultimate goal is to achieve fail-safe operation, which is paramount to the aircraft industry. That is the assurance required by the customers and any lapse on this parties is not tolerated by the traveling public.
.So, guide the Pilot to control the error is the supreme function of safety systems in aircraft automation. The issues involved for causing the error may be many, like Culture, Environment, Terrain, Fatigue, etc. The automation systems help the pilots to create situational awareness. Their critical importance is all the more because pilot error related accidents are up to 80%. Aviation devices are the effects– the preventive techniques. Pilots implement them to avoid risks. So, the interface between human and machine intelligence in aviation is an ongoing game. Automation needs to win in this competition, because there lays the victory of the Pilot and the related personnel that makes the air travel possible and safe for the passengers.
Using of an automation system does not mean that it is a free license for the Pilot to press the buttons and sit quiet. Alertness of the Pilot and other managing staff related to the aircraft gets priority over automation indicators. The Pilot’s judgment is the first alert; it needs to be trusted implicitly. In case of unfortunate mishaps, the Pilot will have to stand in the witness box before the Court of Enquiry, the automation systems are just the mute witnesses. They may be condemned, but the Pilot will be punished. The automation systems need to be given the importance and respect that they deserve; nothing more, nothing less. Under-reliance or over-reliance on automotive systems must be avoided. The skills of the Pilot are more important than the automation itself. Let them always remain sharp and never relax for even seconds. The accidents occur within a matter of split-seconds. Using sixth sense and judgment appropriate to the occasion, is a magical quality. It is acquired by experience a fine sense of anticipation and expertise appropriate to the occasion. The Pilot needs to use his intuitive power to ‘veto’ the suggestions and indicators of automation. The Pilot needs to be a hard and intelligent taskmaster to get the best out of the tools of automation.
Technically one may be a Pilot, but actually he needs to be a “Professor’ as well. Apart from the advancement in aviation technology, he must constantly update himself in related case studies of unfortunate air-mishaps, save-you techniques, analyze the error-situations, build the knowledge base, increase the level f confidence, and sharpen the skills. Learn the lifesaving tips and procedures, because the Pilot is directly responsible for saving the passengers and members of the crew from the moment of take-off till the point of landing.
The other name for every automation system in the aircraft is safety system, to mention a few are, vertical speed value, auto flight director system, flight path control, radio altitude, primary flight display, flight simulator training, aural alert, flight path parameters, aircraft flight operations, flight mode annunciation, vertical speed mode, wind sheer conditions, auto throttle systems, unsafe actions, flight management system, lateral navigation, crew errors, crew resource management, aircraft flight path, mode control panel, aircraft stall and flight operations managers.
It is often said that the judgment of the human being is final over automation. It is not correct to say that automation is perfect, it is a reliable aide. But reliance is needs to be used with discretion. “…..the final authority for decision and action may be traded flexibly and dynamically between humans and automation, and that there can be cases in which automation may be given the final authority for ensuring the safety of a system.”
(Inagaki, Toshiyuki) Human-centered automation is the demand of the modern technologically advanced system. What will be human life without automation is too difficult to imagine. Human being is first among the equals—that is the position and importance of automation now. The power exercised by automation is so much that the interaction is highly complicated. It is the tough bargain between the two, and therefore, authority-designing and sharing is a difficult but inevitable task.
A practical example of safety system in aircraft automation:
An important example of the authority sharing between the Pilot and automation is the Cockpit Task Management (CTM) The Pilot has to perform many functions simultaneously for safe and efficient flying in a modern aircraft. Statistics relating to air crashes reveal that pilot error is responsible for about 65% of such incidents. Of them, significant errors relate to undertaking cockpit tasks. “The cockpit is an environment, in which potentially many important tasks compete for pilot attention at any given time. Cockpit Task Management (CTM) is the process by which pilots selectively attend to tasks in such a way as to achieve the mission goal. It determines which of perhaps many concurrent tasks the pilot(s) attend to at any particular point in time. More specifically, CTM entails initiation of new tasks, monitoring of on-going tasks to determine their status; prioritization of tasks based on their importance, status, urgency, and other factors; allocation of human and machine resources to high priority tasks; interruption and subsequent resumption of lower priority tasks; and termination of tasks that are completed or no longer relevant.” (Funk, Ken) The findings of a research study conducted by NASA, do not speak well for the automation. On classification of the twenty eight incident reports, from the advanced technology sample and 15 from the traditionally sample, startling results emerged relating to task prioritization errors. The conclusion is obvious. CTM is more challenging and n prone to errors in advanced technology aircraft in comparison to the traditional technology aircraft.
Aircraft automation is fine, but it has telling mind-level effects as for the Pilot. Mainly it is the question of budgeting the ‘available time’ with the Pilot, in a given situation. What is equally important is not only the outer mechanism, which is the fruit of automation, but the internal mechanism of the Pilot using the tools of automation. Now the question is how to drive the CTM process to functionally perfect level. Attention is being diverted to other areas of human personality like sociology, psychology and cognitive science research. Tools of better understanding will have to be rediscovered and proper procedures for their functional application is made aware of. The training to the Pilot needs to be suitably remodeled to make him not only a perfect Aviation Engineer, but also a perfect human being. A balanced human being, who has the capacity to work to perfection, under stressful conditions!
Technological advancement is throwing one more serious problem to the safety system in aircraft automation. This time, the challenge is coming from the most unexpected corner. Very Light Jets (VLJ) will come soon, to claim airspace. Will the domestic airspace sufficient to make room for these Jets? From where will the experienced pilots arrive to handle the automaton systems? “Jet aircraft weighing 10,000 pounds or less maximum certificated takeoff weight and certificated for single pilot operations. These aircraft will possess at least some of the following features: (1) advanced cockpit automation, such as moving map GPS and multi-function displays; (2) automated engine and systems management; and (3) integrated auto flight, autopilot and flight-guidance systems.” (Straight,Bill)
And the aircrafts are arriving like an avalanche! In USA, in the next ten years, 4500 additional aircrafts will arrive. Then projection is 300% increase by the year 2025. The burden seems to be too much to handle for the present air traffic control system. Safety systems are going to be tested to the brink. The following Organizations joined together and gave the recommendations in their “NBAA Training Guidelines for Single Pilot Operations of Very Light Jets and Technically Advanced Aircraft.”
NBAA Safety Committee, FAA/Industry Training Standards, Adam Aircraft, Cessna Aircraft Company, Eclipse Aviation, Insurance underwriters, and Training providers
This NBAA guideline offers minimum pilot qualifications to include a Private pilot license, multi-engine rating, and instrument rating. Skills and prior knowledge of basic auto flight procedures, basic FMS (Flight Management Systems), and weather radar were also recommended. The need for a mentor pilot is also indicated. Topmost priority is given to the safety system in these aircrafts which have a high degree of automation can be judged from what is further said in the report: “mentors should be selected from experienced pilots that have ATPs and are type rated in jet aircraft that have technically advanced systems similar to the VLJ in which they will mentor. The prospective mentor needs to be recognized by both the aircraft manufacturer and the insurance underwriter as meeting these criteria. In addition, it is recommended that a training program on the specific aircraft in which they will mentor be completed.”(Straight,Bill)
The former and retired airline pilots have a fresh lease of service life. Their fight experience and airline based training gives authenticity to the aspect of safety. The insurance underwriters feel more confident. Safety is the topmost priority in the next wave in aviation. No one concerned is prepared to make any compromise on the issue of automation-related safety.
“The nation’s air traffic control system is responsible for managing a complex mixture of air traffic from commercial, general, corporate, and military aviation. Despite the strong safety record achieved over the last several decades, the system does suffer occasional serious disruption, often the result of outdated and failed equipment. When equipment failures occur, the safety of passengers and airplanes depends entirely on the skills of controllers and pilots.” (Wickens, Christopher)
Automation proposals do raise the concern that automation may compromise the safety system. Any new system should be such that it should not marginalize the human controller’s ability to take right corrective steps at the right time. Disruptions do not occur always. But when they occur, the alternative remedy provided should be foolproof and must work instantly. The skill of the pilot in times of danger is much more than the ability of all the control systems put together. Automation should lessen the burden of the pilot and certainly not increase his mental pressure. The volume of information is not important for him; the quality of information is!