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Pitot Tube

Pitot tube is the sender of data for barometric instruments and for many other devices.There is an option at these devices that pressure is converting to voltage through the computer.
The pitot tube at Gazelle SA-341,SA-342 will be explained here.
Pitot tube is placed just under the cabine and is is collecting P1 pressure which is consisting from mostly dynamic component and slightly from static.Static component is collecting from two holes placed under the gearbox and engine from both sides of the frame.


Pitot tube components are :
Pressure tube ( 2 ) rilsan,
adapter ( 1)
holder ( 3)
drainage (4 )
montage holder ( 7 )
adapter ( 8 )


Pitot tube with the heater
Heater is necessary device and it is preventing pitot tube from freezing at the same time it ensures good air flow during the cold temperatures.It has its own limitation for work.Each manufacturer has its own and it must be at the manual noted.


There is a complete scheme for connecting it 
At 7 alpha there is a detector and it is pitot warning light controller.During the freezing if the warning light is on and the switch is on,That  is a information for the pilot that he must pay attention at speedometer.


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