A lethal conspiracy of high winds, new snow and a lee slope
At 10.40am, an avalanche started at the top of the gully, triggered the snowslopes below, and gathered them into a massive slide that cascaded as far as the third station level.
When the snow-rubble settled, 15 students from Tokyo, Keio and Nippon Universities had lost their lives. The original caption of the picture below, showing rescue operations near the third station of Tsubakuro-sawa, is “Requiem for our friends who sleep on Mt Fuji”.
Windslab avalanches of the type that swept Mt Maudit this week are less frequent in the Japanese mountains than in the European Alps. That's because Japan's maritime climate produces a warmer, more cohesive snowpack, with fewer avalanche-prone weak layers. But heavy falls of new snow, high winds and a lee slope – as on the east side of Mt Fuji – can combine for deadly effect on any high mountain.
Guardian newspaper: Mont Blanc avalanche was unavoidable, say authorities
Photos are from 目で見る日本登山史, 山と溪谷社 (編集) (Yama-to-Keikoku-sha: Illustrated History of Japanese Mountaineering)
More about the power of snow in the Japanese mountains: Avalanche