Bill Whitefield
Member
During a recent flight I noticed that my airspeed did not match up with my power settings. The airspeed did not appear until 25 knots, at 1,800 feet and full power the airspeed indicated 135 knots while the gps ground speed was 180 knots in a no wind condition, and the typical power settings in the pattern yielded much lower indicated airspeeds. The problem seems to be caused by an obstruction in the pitot tube. The plane has a Dynon unheated pitot tube with AOA. Disconnecting the plumbing at the inspection panel and blowing air back toward the tip of the pitot did not yield any debris. I have also attempted to use .032 safety wire to dislodge the blockage. The wire would go in about 3 inches and then stop. Eventually I was able to get the wire to the back of the tube but there was resistance the entire length. A test flight yielded the same results as before. I have a #40 drill bit that is long enough to run down the length of the tube and am thinking about using it (unpowered) to see it the blockage can be cleared. Any thoughts?
Bill
Bill