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Old 18th Apr 2009, 07:42
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King on a Wing
 
Join Date: Apr 2009
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Yes my friends,
I had an opportunity to speak to some of my more errm 'techically qualified' colleagues.As in AME's on the line who work in major maintenence on the system.And Mr Fixer seems to have nailed it spot on.This airplane has some 20 sensors per tank.Each of these is effectively a "radio doppler".And works on the same principle.Calculates the height of fluid by measuring the difference in the speed of the sonic signal sent out thru one sensor to another,as against the ACTUAL local speed of sound(which is a preset value) thru standard temp air.This difference is then converted very accurately into height in the tank in mm.Which translates into quantity of fuel AT THAT sensor given the actual specific gravity of fuel at that point........(Whew.....!!!)
Now that's what I understood.....
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