The Glass Turret

My grandfather - Grandy - was a teller of stories, and I have been carrying a few of them around for a long time.

He grew up in Glasgow, in the tenements, where the front doors of two flats faced each other across a narrow landing. As a boy he would tie the two door handles together with a length of rope, knock hard on both, and run. Behind him the two neighbours would each pull their door, and each would feel it pulled shut from the other side, and they would set to fighting it out between them while the boy was already three streets away. I think about this when I imagine what my grandfather was like before he was anyone's grandfather. A boy with quick hands and a quicker exit.

He joined the RAF by lying about his age. He was too young, so he made himself older on the paperwork, and got in. His mother and father were not happy about it. By then it was done.

He flew in a Lancaster as a flight engineer. He sat beside the pilot, and the mechanical life of the aircraft was his to keep: the four Merlin engines, the fuel he balanced from tank to tank to hold them steady and stretch the range, the hydraulics and the electrics, the boost and the gauges that told him whether they would make it home. He helped the pilot haul the heavy thing off the ground at take-off and set it back down at landing, and in an emergency it fell to him to work the fuel figures - fast, and right, with no room to be wrong. He was the reserve bomb-aimer too, and another pair of eyes on the dark for fighters.

So sometimes, on the runs over the German factories, the bombsight was his - the work, at the end of all that distance and all that danger, of putting the bombs where they were meant to go. He used to say that he would call out up a bit and down a bit over the intercom, as a small dry joke, because at that altitude up and down did nothing at all; a bomber of that kind had to hold its height. Left and right were the real commands, the ones that mattered, the ones that actually moved the thing they had flown all that way to deliver on their designated target. So he made the useless joke on purpose, lightly, with everyone's lives in the balance and the work as serious as work ever gets.

And there is the one I cannot put down.

There was a glass turret on the top of the aircraft, a clear dome a man could stand up into and see out across the whole dark sky. Grandy had been standing in it, looking out trying to spot the danger. Then, for some reason - I do not know what reason, perhaps no reason at all - he stepped back down out of it. Seconds later a piece of shrapnel came through the glass, through the exact place where his head had just been.

Seconds. A man steps down for no particular reason, and the space where he was is torn open, and he lives, and everything that comes after him gets to exist.

I think about this more than I would expect to. My grandfather, my father, my own self, my children - all of it threaded back through a few seconds and a turret of glass over Germany. I am here, writing this, because an old man who tied door handles together for fun happened to climb down at the right moment.

He told these stories the way he tied the rope: lightly, for the fun of it, the weight tucked underneath. I am only now beginning to feel the weight that was always under them.

Henry "Jock" Sturrock, my grandfather, died aged 97. Sheffield's last alderman and RAF veteran · The Veterans Foundation's tribute