Man and Machine — Page 292, Lesson 482

I want to walk you through the final part of the Man and Machine chapter, where we wrap up automation and move into intelligent flight decks and colour displays. First, two quick practical tips that the book gives you: if you see a piece of information on a display that you don't understand, double-check it — it could be wrong. And take any opportunity you can get for extra simulator training. Those are the kind of habits that separate a professional pilot from someone who just goes through the motions. Now, the automation summary. Aircraft automation is gaining ground and it's here to stay. I want you to think of it as a tool — and as we've seen throughout this chapter, it is far from a panacea, meaning it's not a cure-all. Automation has gone a long way toward solving many of the traditional problems that pilots used to face, but in its wake, it brings problems of its own. Like any tool, its effectiveness depends entirely on the user — on you. It has to be handled in the correct way, and with an awareness of its weaknesses and dangers. Used badly, automation can lead to catastrophic results. Handled well, it becomes a major contributor to flight safety. That brings us to intelligent flight decks. There is no precise dividing line between what we call 'automated' and what we call 'intelligent'. But the problem-solving and data evaluation that modern computers are capable of would merit terms like 'pilot's associate' or 'electronic crew member'. However, there are three main human factors issues that we can identify. First: how much autonomy should we give to the machine? Should the computer be allowed to evaluate information, make decisions, and execute them without reference to the pilot? Or should it remain in an advisory role, presenting suggestions to the pilot to assist him in making the necessary decisions? A concrete example: should an aircraft fitted with a GPWS — Ground Proximity Warning System — take automatic climb action on receipt of a terrain warning, or should it just alert the pilot and let him decide? Second: as machines become more complex, they evaluate greater quantities of possibly 'noisy' data. 'Noisy' data means data that has errors, interference, or uncertainty mixed in. Any increase in this noisy data will lead to an increase in 'probabilistic' solutions — meaning the computer's output is a best guess based on probabilities, not a certainty. And here's the critical point: present aircraft displays do not give the pilot any estimate of the reliability of the data displayed. They simply display the machine's best guess. You don't get a confidence indicator. Third, and related: the computer uses information from both its internal inertial system and ground-based fixing aids — things like VORs. But the pilot is given the same display regardless of whether the aircraft 'knows' that good data is being received from all sources, or whether the computer 'knows' that it is receiving information from, for example, two poor cross-cuts, distant VORs, or an inertial system that has been drifting for a number of hours. The display looks the same in both cases. You, as the pilot, have no way to tell from the screen alone that the underlying data quality is degraded. This leads to a key point about trust. Pilots must have an appropriate level of trust in their equipment. Under-trust — not trusting the equipment enough — can lead to unnecessary workload because you're constantly double-checking things that are fine. Over-trust has obvious dangers — you stop monitoring and let the automation lead you into trouble. Modern equipment is normally very reliable, and the perceived reliability — how reliable you think it is — will determine the amount of trust you actually place in it. Another factor: the modern display may be so compelling, so polished and convincing, that it generates more trust than it actually deserves. Finally, let's talk about colour displays. Where colour is used to indicate a change of state — for example, from 'ALT capture' shown in blue to 'ALT hold' shown in green — the colour change should be accompanied by a change of caption or location. The change of colour by itself is not normally sufficient to ensure that the crew will notice the difference. So if you're designing or operating a system, you can't rely on colour alone to grab the crew's attention; you need a text change or a position change as well.