Read this brilliant book about the end of Braniff called 'Splash Of Colo(u)rs'. There was a few paragraphs in a section about Panagra about South American operations (praising the airline's safety record in a potentially treacherous part of the world). La Paz is so high that pilots need to go on oxygen as soon as they get into the cockpit because at that altitude their conciousness is impaired. One crew didn't do it for one reason or another (they felt fine I guess) but a mistake was made in the speed calculations and they rotated 20 kts too early. In a partially stalled condition the DC8 lifted off then just hung there above the ground without climbing or accelerating. They lifted the gear and roared past the end of the runway and out over a flat plain at an altitude allegedly not exceeding 20 ft for the first minute. According to the author (a pilot), the only thing keeping them up was 'ground effect', the cushion of air that develops under the wing when it's just above the ground. A few extra knots (or a gentle puff of a headwind) gradually lifted them a few feet at a time until they got to V2 and started climbing. Apparently the DC8 left a massive spray of dust (like a pickup truck on a dirt road) in the air in it's wake.

(a) Anyone else know about the oxygen requirements in this scenario; and (b) great story, huh?