Pitot (Tube)

Pitot Tube: A pitot tube opens towards the direction of flight on an airplane and senses the aircraft velocity. The physics were discovered by Henri Pitot in the 18th century. It fails it becomes blocked by debris or ice. For this reason the pitot tube is usually heated.

There was an unpleasant story that the crash had been due to General Cairn's failure to turn on his aircraft's pitot heater.

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