I posted my static port issue in another thread but it has branched out into a problem I can't seem to solve on my VS indication.
I was able to change my static ports to the Van's pop-rivet type and it corrected my static source error to <1 KTAS, which is great! However, I now get these spikes in static pressure which mainly cause variation in VS indication. See this video...https://www.youtube.com/watch?v=7iFLKqXmxAw
I played around with modeling clay and creating a smooth transition around the static port "rivet" but it didn't help with the static pressure variations/spikes that cause these uncommanded variations in the VS (see video). I tried to isolate it to a specific port but it was occurring on both ports, with the left port slightly worse. Opening the alternate static source to the cabin fixed it, so this tells me it's something outside. I checked for static leaks and there is zero leak rate in my static system.
I also tried using a .004" and .008' gauge snubber on the GSU25s and went for a test flight. Both seemed to do the job with .004" doing a little bit better, but there does seem to be slight lag VS indication. I'm not sure this is a good solution, and may have some unintended risk associated with it.
I'm wondering if anyone else has seen this behavior or have any recommendations.
My next steps will be to tuff test the airflow on the fuselage and record the results. Also, I replaced the old vinyl 1/2 and 1/4 tubing that was installed with new tubing that was all 1/4" poly...wondering if going to all 1/4" would make VS indication more sensitive and thus the reason some 1/2" was installed, acting as a shock absorber in pressure pulses.
Any thoughts?
I was able to change my static ports to the Van's pop-rivet type and it corrected my static source error to <1 KTAS, which is great! However, I now get these spikes in static pressure which mainly cause variation in VS indication. See this video...https://www.youtube.com/watch?v=7iFLKqXmxAw
I played around with modeling clay and creating a smooth transition around the static port "rivet" but it didn't help with the static pressure variations/spikes that cause these uncommanded variations in the VS (see video). I tried to isolate it to a specific port but it was occurring on both ports, with the left port slightly worse. Opening the alternate static source to the cabin fixed it, so this tells me it's something outside. I checked for static leaks and there is zero leak rate in my static system.
I also tried using a .004" and .008' gauge snubber on the GSU25s and went for a test flight. Both seemed to do the job with .004" doing a little bit better, but there does seem to be slight lag VS indication. I'm not sure this is a good solution, and may have some unintended risk associated with it.
I'm wondering if anyone else has seen this behavior or have any recommendations.
My next steps will be to tuff test the airflow on the fuselage and record the results. Also, I replaced the old vinyl 1/2 and 1/4 tubing that was installed with new tubing that was all 1/4" poly...wondering if going to all 1/4" would make VS indication more sensitive and thus the reason some 1/2" was installed, acting as a shock absorber in pressure pulses.
Any thoughts?
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