Clarity of vision

I remember standing at a bus stop in Aberdeen when I was a student in the 1960s and realising that I could not quite read the destination on the front of the approaching bus very clearly. I did nothing about it. I was 20 years old and immortal.

In 1970 the Commonwealth Games came to Edinburgh for the first time. We got tickets for various events. On one occasion we travelled from Linlithgow, where we had not long bought a house, by train. There was a station adjacent to Meadowbank stadium. But it was a slow journey.

So when we later attended some of the badminton competition in an evening, we drove in our elderly car. It may have been that there simply were no trains at the required times. I just don't remember.

The drive home predated the building of the motorway between Edinburgh and Linlithgow and was a twisty-turnie local road. It was slightly alarming. I found myself seeing two lines in the middle of the road. Not the normal double white line that prohibits drivers from crossing to the other lane of the road to overtake. Rather, I was seeing a second line displaced above and slightly to the side of the actual single line painted on the road.

I dismissed this as tiredness. But my spouse, who had been travelling with me, was not so easily persuaded. A visit to the optician was mandated.

The experience from Aberdeen a few years earlier when the bus number was blurry was repeated when confronted by the letters on the chart before me. I had astigmatism. Not too surprising as my father also wore glasses to correct his similar defect. Heredity strikes.

But the reality is that almost everyone has a bit of this particular defect. Mostly not to the extent of  requiring any corrective action.

Like anyone confronting a health issue for the first time, I wanted it explained to me.

We imagine that our eyes are perfect spheres. As uniform as a tennis ball in their circularity. Not so. The curvature of the eye varies a bit. That means that the lens at the front through which we see the world has variable curves.

The lens in our eye is an interesting thing because it is soft and flexible. The muscles around the eye pull it into different shapes. It's one shape when we gaze at the horizon. Another when we try to read a bus number 100 metres away. Finally, reading a book 50 centimetres away requires a quite different shape.

These muscles really earn their keep. As all muscles in our body, they become gradually less strong as we age. That's one of the reasons our eyesight deteriorates as we get older. Or does it?

One of my flying pals, I last piloted an aircraft in 2014 - I just ran out of time to do enough of it to be sharp enough to keep flying, had the experience of improved eyesight with age.

His annual medical showed that, in his late sixties, he no longer required glasses to fly. A miracle? Not quite. It simply meant that his eyesight for distance, in particular, had changed with age. The "improvement" was at the expense of his being able to read without glasses.

In 1991 I discovered that you only needed one eye to be a pilot. I was one of two pilots doing a favour by flying a Piper Cherokee-Six from France to Bristol. The aircraft had four fuel tanks; the drain below one of them was leaking. Fuel, therefore, kept pouring out of that tank. Maybe not pouring, but certainly much more than dripping.

In flying, we have quite a few "aide memoir" to enable us to remember memorised check-lists for certain purposes. One of these is "FREDA"-which we use every 30 minutes. It is; "Fuel" (change tanks), "Radio" (check listening on correct frequency), "Engine" (clear carburettor ice), "Direction Indicator" (re-align with wet compass), "Altimeter" (check correct barometric pressure set).

So as we flew north from France we would have normally swopped fuel tanks every 30 minutes. That keeps the aircraft flying level because the weight in the tanks, they are in the wings, are equalised.

But on this occasion, we just stuck with the leaky tank. It was better to burn what we could rather than let it drop out.

The owner of the aircraft was a pop star, alas I cannot recall who - this was 30 years ago, and the aircraft registration was G-ETBY. Apparently "Get By" was a song recorded by him.

I am writing about this because he was also a pilot but only had one working eye. Up until then, I did not know you could fly with just one. Although we were taking his aircraft to Bristol we were dropping him off at Fairoaks which is a very busy small airfield inside Heathrow's airspace.

We had had a wee bit of difficulty as we approached the Isle of Wight. The radio navigation beacon at Southampton which we had intended to navigate to was off. Visibility just, only just, allowed to follow our route by eyeball.

Things would get worse.

We swapped seats for flying from Fairoaks to Bristol. I left the Captain's chair. My colleague started up and obtained permission to taxi off our stand. But the aircraft would not move. He'd not checked that the wheel chocks had been removed; they were still in place.

And now?

We were cleared for take-off and then climbing out heading West when the engine just stopped at 1,200 feet off the ground. In our desperation to burn fuel from the leaking tank, we had forgotten that it might now be empty. I say "we", but from where I was sitting I could not see what tank the Captain had selected. I am not sure it matters but; I was the amateur pilot, the one now flying was a professional.

With my taking control of what was now a glider, another fuel tank was selected, the engine was restarted, and we climbed away from the 700 feet above the ground to which we had sunk. There was no conversation during the rest of our flight. And I cancelled my intended snooze in favour of keeping a close eye on what was going on.

So even with four eyes contributing to safety on our journey, we were capable of being incapable.

The astigmatism in my eyes to which I referred to earlier has now been joined by myopia, hypermetropia, presbyopia and low light myopia. Nothing unusual. It's just age. It means my specs are now more complex and more expensive.

But from my first visit to an optician, as would be the case in any mildly intelligent person's case, I have always asked for a full explanation of any diagnosis of shortcomings in my vision. Hence, my ability to provide a layperson's description of my eyes' limitations.

Almost every person who has spectacles will have visited an optician. And have had that serious talk about how important eyes are. Heard about the need to avoid actions such as driving, which depend on their proper operation, if there appears to be a problem.

Even if such advice has been forgotten, we should all be able to work out that we should not to take to the sky, or the road, with eyes which we know are not functioning properly.

Clarity of vision is important in politics. It's vital on the road.

Just saying.