Far too often I have experienced a degraded pitot indication (several times all the way to GPS Assist). On five specific occasions conditions were not particularly prone to generate ice but the pitot froze while the heat was on and the controller was modulating the current draw.
The system has never been able to clear a frozen pitot. One flight extended for nearly 3 hours in bright sun and the pitot only cleared on decent when the OSA rose above freezing.
From my observation of the amp draw from the controller; it is cycling the power down to heat the pitot far to early. There is clearly sufficient power available but it never gets delivered to the heating element.
Typically, the amp draw will go to 10A or so and quickly step down to 5 then 0... then pause a bit and repeat.
As the pitot begins to degrade the autopilot will go a bit bonkers and start to hunt and overshoot dramatically and the EIFS becomes VERY unreliable. Although it is obvious that the pitot is partially frozen but there is nothing to be done with the EIFS until it is completely frozen and the system goes to GPS Assist where the system is once again usable for reference.
I would very much like to have a reliable way to clear a frozen pitot... can the controller be bypassed to provide for full on function???
A way to select GPS assist would also help to restore usable flight reference when the pitot is causing erratic indications but is not yet completely blocked... I have observed this condition as persistent well in excess of 15 minutes.
Perhaps my controller, heating element, or temperature sensor is bad?
Can the two white wires of the temperature sensor be tied together some way to force a higher current draw?
Any help is much appreciated as I am really not fond of flying with a partially frozen pitot...
On a high note... the GPS Assist mode ROCKS!
The system has never been able to clear a frozen pitot. One flight extended for nearly 3 hours in bright sun and the pitot only cleared on decent when the OSA rose above freezing.
From my observation of the amp draw from the controller; it is cycling the power down to heat the pitot far to early. There is clearly sufficient power available but it never gets delivered to the heating element.
Typically, the amp draw will go to 10A or so and quickly step down to 5 then 0... then pause a bit and repeat.
As the pitot begins to degrade the autopilot will go a bit bonkers and start to hunt and overshoot dramatically and the EIFS becomes VERY unreliable. Although it is obvious that the pitot is partially frozen but there is nothing to be done with the EIFS until it is completely frozen and the system goes to GPS Assist where the system is once again usable for reference.
I would very much like to have a reliable way to clear a frozen pitot... can the controller be bypassed to provide for full on function???
A way to select GPS assist would also help to restore usable flight reference when the pitot is causing erratic indications but is not yet completely blocked... I have observed this condition as persistent well in excess of 15 minutes.
Perhaps my controller, heating element, or temperature sensor is bad?
Can the two white wires of the temperature sensor be tied together some way to force a higher current draw?
Any help is much appreciated as I am really not fond of flying with a partially frozen pitot...
On a high note... the GPS Assist mode ROCKS!
