Pitot static system
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- Joined: Tue May 24, 2022 3:19 pm
- Name: Andrew B
- Location: Northern California
- Aircraft Type: C-120
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Pitot static system
So I’ve become aware of the static gremlin that apparently plagues out aircraft. My instruments were vented to cabin pressure including the asi. I put a transponder in so decided to put in nice new static line and hook everything together to the wing mounted “static tube”. Went for a test flight and my airspeed was way off so I aborted the takeoff popped the static line off of the encoder and tried again with results more like what I’m use to. So Has anyone found a good fix other than just venting to cabin pressure? Maybe dual static ports on either side of the cabin or…..? Im happy just venting it to cabin pressure but curious if anyone has ever went down this rabbit hole?
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- Name: Matt
- Location: 9B8 CT
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Re: Pitot static system
I haven’t heard of a wing mounted “static tube”.
I have a static port on the pilot’s side of the plane that connects to the airspeed, altimeter, VSI, and encoder. My wing mounted pitot tube just connects to my airspeed indicator.
I have a static port on the pilot’s side of the plane that connects to the airspeed, altimeter, VSI, and encoder. My wing mounted pitot tube just connects to my airspeed indicator.
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Re: Pitot static system
There is a diagram of how to bend it to be properly aligned somewhere on here. I looked at that diagram and the wing airfoil shape and decided that a straightedge from the trailing edge along the bottom of the wing was close to the line that the tube should be parallel to and slightly below (about 1 inch by memory). I did that and mine got closer, but still reads low.
Of course as soon as you get it aligned you will run into it by accident and bend it and change it anyway.
Of course as soon as you get it aligned you will run into it by accident and bend it and change it anyway.
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- Name: John C
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- Aircraft Type: 1946 C140/C90
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Re: Pitot static system
Planes up to SN 10299 came with a static tube under the pitot tube, basically a second pitot tube with blocked tip and cross drilled holes in the sides. My guess is if it's not working it's either blocked or there's an leak in the plumbing inside the wing somewhere. The static port on the side of the boot cowl came after, and is pretty bullet proof except if you're in a radical slip.
John Cooper
www.skyportservices.net
www.skyportservices.net