How did we survive? Because our wheels were down and the ground we hit was flat. It was the runway at Bolivia's El Alto airport - nearly two-and-a-half miles above sea level.
Inside the pressurised cabin all was well. But once I stepped into the airport passageway Ibegan to do an impression of Billy Connolly doing an impression of a Glasgow drunk trying to eat a fish supper. I kept listing to the left, continually bumping off the passageway wall.
I wasn't the only one. Most of the passengers walked at a snail's pace to keep their balance. Some were taken by airport personnel to an "oxygen room" beside the baggage carousel, where they breathed into scuba-style oxygen tanks until they got used to the rarefied air.
El Alto serves La Paz, at 11,800ft one of the world's highest cities. And even though the capital lies more than 1,200ft lower than the airport - the road trip is a bit like sliding down a curving water chute - living in La Paz takes a bit of getting used to.
Strangers, and even Bolivians coming in from the lower cities, are usually hit withsoroche, or altitude sickness. With the thinner oxygen levels, the heart and lungs must work much harder. Visitors have been known to drop dead, although the government likes to keep a lid on such cases or suggest some other cause. A Canadian died last year after flying in from the low-level city of Santa Cruz.
My wobbly arrival was an early symptom. Within hours I had a searing headache above the back of my neck. I'm in good shape but I was out of breath after getting up from a chair. The locals swear by mate de coca, or tea made from coca leaves, with lemon juice squeezed in. It certainly helped me. The Incas, and later the Spaniards, used to provide coca leaf to miners to numb their aches and pains and allow them to work harder and longer. The aculli, or coca-chewing break, remains the Bolivian equivalent of the English tea break.
When my headache persisted on the third day, I cast aside my dislike for medicaments and took the locally recommended "Sorojchi Pill", which slows the heartbeat and induces deeper breaths. It did the trick and I was relatively normal by the fourth day. I learnt not to eat heavily or late at night - digestion takes longer - and to drink pint after pint of water to avoid dehydration. Also, to cut down on alcohol since high- altitude hangovers are a living hell.
And I learnt to walk slowly. La Paz is one big hillside and you don't see residents rushing around. It's a bit like watching a film in slow motion.
But the pacenos, as the city's residents are known, are well used to the altitude and its effects. Walking up the central Prado avenue into the afternoon sun, almost everyone covers their face with a book or magazine to stave off the ultraviolet rays.
And take football. At this altitude, the ball flies faster and higher, bounces more, and is difficult to control. Combined with the extra strain on lungs and heart, it is no wonder foreign teams hate to come here.
Little Bolivia handed mighty Brazil one of its rare defeats in a World Cup qualifier here in 1993. Acclimatisation generally takes a day or two. The Brazilians had flown in just before the match, and they left exhausted.
Marathon runners, walkers, cyclists and boxers, on the other hand, regularly come here to train, testing their hearts and lungs to the limit so that performing at sea level seems like a cakewalk.
British residents complain that their tea never tastes quite the same as at home. This is because the water boils at 88C rather than 100C. On the other hand, fresh produce keeps longer outside the fridge, and there are few, if any, mosquitos or other pesky insects because of the cool, thin air.
Reluctant passive smokers will be delighted to know that cigarettes left in ashtrays go out rapidly because of the lack of oxygen. For the same reason, there are few fires in this town. Locals like to joke about the idleness of the Fire Brigade, although its men often do fine work in mountain rescue.
Unlike most hillside cities in the world, the poor live in the heights while the wealthy build their houses down below, where there is more air to breathe. El Alto is surrounded by shanty towns, while the Zona Sur (Southern Zone), a couple of thousand feet lower down, is favoured by the rich, famous and representatives of Her Majesty's government.