Originally Posted by BillL
Please post a picture of your static port as installed. This will help.
Thanks all for the replies. I collected and analyzed more data and confirmed that my IAS is reading low across the speed range, suggesting high pressure in the static system.
I am posting pictures of my static ports and would welcome any thoughts.
How do I know IAS is low? I ran the three-leg test recording GPS ground speed, averaging it to adjust for wind, corrected to TAS using an electronic E6B for temperature, altitude and altimeter setting. I consistently found IAS 4-5 MPH low at pattern and approach speeds and 7-9 MPH low at cruise.
This suggests that the pressure differential between the pitot and static lines is less than it ought to be, meaning either the pitot side is too low or the static side is too high. I did a leak-test on the pitot side and found no significant leak-down. So my suspicion is that the static ports are somehow resulting in high pressure.
Is my logic sound?