Physiology

Flying exposes us to quite a lot of challenges:

We reach heights in the atmosphere where life is impossible, we are subjected to forces with which we are not familiar and experience sensations that can seem very strange.

In addition, flying a plane requires a substantial cognitive effort.

The weakest link in the whole aviation scene is and remains the human being, the vast majority of all aviation accidents are attributable to human 'error'.

How it comes that people make mistakes or take less fortunate decisions and what we can do to avoid this as much as possible is mainly the subject of the Psychology section.

In this chapter we will discuss Physiology: the discipline that deals with the functioning of the body, here we are of course talking about humans but on a physical and chemical level we do not differ that much from animals.

We first discuss the behaviour of gases, and their interaction with liquids, with particular attention to the acid-fuel fraction that is part of the atmospheric air and its interaction with the blood. In this context, we also consider the effects of pressure changes due to ascent or descent.

 

Then we will deal with the influences of large forces on our body, inherent to motorised locomotion and which can become extreme during aerobatic manoevers.

Next, we focus on the sensory perceptions such as sight, hearing and our positional sense as well as what our brain tells us about them in flight and how this can lead to some common illusions.

We end with a section on how to take care of our health, what to do in case of illness, and with some recommendations on how to deal with our passengers.

As pilots we are responsible for our condition and fitness, a critical review of which is part of the overall situational awareness that flying requires of us.

We must not forget that our medical fitness to fly depends not only on whether or not we feel well or on our physical condition at the time, but also on the risk of sudden incapacitation such as heart attack, stroke, sudden nausea, loss of consciousness, convulsions, etc., we must realise that despite having a good physical condition and feeling very fit, the risk of sudden incapacitation is completely separate from this. The ultimate right to decide on our fitness for flight lies with aviation medicine.