20 Things You Didn’t Know About On Her Majesty’s Secret Service (1969)
9. “A Grave Deep Enough, I Think, To Prevent Even Double-0 Seven From Walking.”
The Swiss Army planted explosives in an avalanche zone in summer 1968 so that Peter Hunt could film an avalanche in spring 1969. Hunt set up remote-controlled cameras and mannequins of Bond and Tracy beforehand, but the snow and ice unexpectedly fell of its own accord.
Insisting on filming the disaster that Blofeld creates to prevent Double-0 Seven and Tracy from escaping, Hunt asked second unit director (and later editor), John Glen to rescue the sequence.
Fortunately, the Army and location manager, Hubert Fröehlich found a new location in Switzerland - the Tschingel ridge - and positioned cameras a safe distance away on the Ebenhorn. Despite this, the subsequent "controlled" avalanche buried the crew in four feet of snow. Luckily, no-one was injured, despite Fröehlich's estimation that 125 miles of snow had fallen from the peak!
Realising how precious the footage was, Glen flew it to Pinewood Studios on two separate aeroplanes in case there was an accident. He had even shot the avalanche in stereo and new speakers were installed at the Odeon in Leicester Square to allow audiences to appreciate the harrowing sequence.