After I took delivery of my PA-28-180 and flew her home a couple of months ago, I noticed towards the end of the 4 hour flight as I was nearing my destination that the needle on my vertical speed indicator started bouncing rapidly. For example, when I was descending and it was showing a VS of approximately 500 FPM the needle was bouncing rapidly in the 500 FPM range between 400 and 600 FPM. My first couple of flights after that first one resulted in a recurrence only once or twice, but since then it happens on every flight, with the needle bouncing rapidly across an approximately 200 FPM range. It only seems to occur when I'm either climbing or descending, with the bounce becoming more pronounced as the vertical speed increases. Also, when the plane is on the ground and engine is off the needle never sits on zero, it's either around 100 feet above or below the zero FPM indicator. I used the adjustment screw to reset it to zero before flight, but after I land and shut down the needle is again off zero.
Does anyone know if this problem is indicative of an issue with my VSI or if it could be a problem with my static system?
Does anyone know if this problem is indicative of an issue with my VSI or if it could be a problem with my static system?
