Sunday, September 7, 2014

Hypoxia, Larry Glazer, TBM 900 KN


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When pilot in command is no longer in command


"Atlanta Center, TBM double 0 Kilo November, there is something wrong with my plane; request 18 thousand." -- "00 Kilo November, I can give you 24 thousand, is this an emergency?" (or something to that effect)


A fatal response. The words, "There is something wrong with my plane," above FL 30 in a single engine, single pilot aircraft is in itself an implied emergency. This may be a stretch for a controller, but FAA should have protocols in place to respond to the likelihood of hypoxia. Regulations require an oxygen mask immediately available to the pilot at these altitudes. Presumably the loss of cabin pressure was insidious and the pilot was already hypoxic when he made the call. At those altitudes the pilot has only a matter of seconds for rational behavior.
Better the controller had responded with, "Set altimeter to 10,000 feet and apply oxygen mask immediately. Emergency descent authorized. Report passing every thousand feet." Then the controller might clear the airspace and call a supervisor, but he or she can hardly feel responsible unless briefed on the insidious nature of hypoxia and have procedures in place to respond to that likelihood.
Nothing new about this, I imagine nearly every IFR pilot cringes when hearing of this unfortunate tragedy, with similar thoughts in mind. The FAA has altitude chamber experiences available in Oklahoma City, Pet Field in Colorado Springs and probably elsewhere. The instant fog of cold air and rapid loss of judgment will make you an instant believer. Holding your breath doesn't work. In fact you can't without hurting your lungs.
Additionally, anything less than a military style oxygen mask is inadequate, preferably positive pressure oxygen. Nasal oxygen is worthless. You need the rebreathing bag to keep your CO2 in functional range. With the cabin altitude creeping or exploding above 12,000 feet red lights should have been flashing all over the place. There is no time for complacency or discussion.
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