They were well-acclimatised to altitude, having wintered over at 5800 metres near the base of the peak as part of the Silver Hut Scientific Expedition of 1960-61, led by Sir Edmund Hillary.
De var godt akklimatiseret til højden efter at have overvintret på over 5800 meters højde nær bunden af bjerget, som en del af den videnskabelige ekspedition Silver Hut (1960-1961), ledet af Sir Edmund Hillary.