Oops, calculation error. I meant to change units in the GPS from Knots to MPH, but forgot. After converting the GPS Knots, I'm indicating 15 MPH faster than actual at 75 MPH indicated, ane 16 MPH faster at 100 MPH indicated. Still needs to be fixed and this is more in line with what I'm observing when doing stalls and approaches.
Dave --- In [email protected], "bigbrownpi...@..." <bigbrownpi...@...> wrote: > > Got home from my UPS trip this morning and went up this afternoon to see how > much my indicated airspeed was in error. First, I checked the pitot tube-- > it was 3 1/4" from the lower surface of the wing, so I adjusted it gently to > 3 7/8". It is not parallel to the lower surface of the wing, but canted > slightly down after the adjustment. Next, I checked the pitot and static > lines at the left wing joint. There is clear plastic tubing joining both > lines secured with safety wire wrapped around the ends. I could not really > access the tubing to check it, but it appears to be fairly new and in good > condition. There is also a metal line coming from the center section that is > no longer connected to anything and it is open on the end. After that, I > went up and flew South, East and West at 75 MPH indicated and 100 MPH > indicated and logged the groundspeeds I saw on the GPS for each leg. After > feeding them into the web-based program linked from Ed's Coupe Site, I got a > +23 MPH error at 75 MPH indicated and +27 MPH error at 100 MPH indicated. I > ordered a new UMA airspeed indicator from Aircraft Spruce with proper range > markings when I got home. Hope that fixes it! > > Later, > Dave >
