Early warning

Prof Scurlocksuggests there are predictable cold spots in wing tanks where the first tiny crystals form

Prof Scurlock (letters October 2013) suggests there are predictable cold spots in wing tanks where the first tiny crystals form. If so, it should be possible to detect them with with something akin to an optical smoke detector immersed in the fuel. Such sensors could easily be made (in the electrical sense) intrinsically safe, small, and require very little power. Given this early warning, the pilot could descend to a warmer altitude. 

John Cole, Yelverton Devon

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