My brother, Peter, died near K2 in the Himalayas in 1983. Three years later, I flew to Pakistan, where I went on a mountaineering expedition in his memory. I was supposed to return from Karachi to the UK on Pam Am flight 73, but the plane never took off. Instead, the Boeing 747 was hijacked by a Palestinian terrorist group, armed with Kalashnikov rifles and explosives.
At the time the terrorists announced themselves, I was still struggling with my hand-luggage. I heard a noise in the doorway and looked up to see a man with a gun struggling with the flight attendant. One man shouted: "Where is the captain? This is a hijack; put your hands in the air!" Thankfully, it took a while for them to get into the cockpit, by which time the pilots had immobilised the plane and escaped.
The hijackers moved the passengers to the back of the plane, as a stewardess made the most terrifying announcement I've ever heard: "Ladies and gentlemen, the group responsible apologises for the inconvenience caused. Their argument is not with you, they do not wish to hurt anybody; but if you make any sudden movements, you will be shot."
What we didn't know was that the terrorists had already killed one of the passengers. I didn't hear the shot, which seems unbelievable, but I was hunched in my seat, trying to be inconspicuous. The hijackers seized our passports, and after two hours, they randomly selected my name from these. They called me forward, at which point I was convinced they were going to shoot me. I tried to say something about my brother, to say: "Please don't kill me, my parents have got no one else". But the leader just waved his hand at me as if to say, "I'm too busy for that". Then I was made to kneel in front of him.
There I stayed, for almost 12 hours, while a Pan Am official on the ground with a megaphone tried to negotiate with the terrorists from under the wing of the plane. Finally, I was ordered to the back of the plane with the other hostages. I was momentarily relieved, but suddenly the hijackers started to throw hand grenades, and moments later, uttering cries of "Jihad", they emptied their Kalashnikovs in seconds, killing 20 people and horrifically injuring many more.
The plane filled with smoke. I was covered in blood but unhurt, and realised they'd run out of ammunition. This was my chance. I managed to make it out of a door and jump to safety from the wing. I hid in a nearby building until a soldier found me. I was astonished to be alive and unscathed amid such chaos and death.
In the long term, the experience has left me with an appreciation of how precious life is. I wouldn't say that every day is full of unmitigated joy, but I certainly have a heightened sense of life's beauty.
'What Happened to the Hippy Man? Hijack Hostage Survivor' by Mike Thexton is published by Lanista Partners, £17.99