Todd, You need to look very closely for an error in your plumbing or configuration. Your description of your pitot/static system mirrors both Larry's and mine. My ASI has always been relatively accurate when corrected for altitude, as is my VSI and Altimeter. I don't have any close up photos of my pitot/static mast, but there are photos of it at <http://jscott.comlu.com/props/PrinceProp.html> It has the pitot and static tubes bent and welded together. Mine is the unit listed in the Aircraft Spruce catalog as part #15144. <http://www.aircraftspruce.com/catalog/inpages/pitot15144.php> I have used this pitot static configuration on numerous planes with no serious inaccuracies. If this is the same unit you have, and it is mounted correctly, I would say you need to take a serious look at the plumbing.
You will note that my pitot mast is mounted in the outer wing panel well out side of the prop blast. If yours is in the prop affected area, that may explain your issue. There is nothing wrong with the type of static port Dan uses either. In fact, it tends to be a bit more accurate, but we're really only talking minor nits in accuracy, where your issue seems to be a major league ball park issue. -Jeff Scott Los Alamos, NM N1213W ----- Original Message ----- I had the AP/AI at my hangar attach a test apparatus on the pito tube. and the ASI was within 1-2 mph with every airspeed he dialed in. This was sitting on the ground while using either the wing static source, or behind the panel static source. Makes me think the ASI is okay, and that the problem is whichever source I try it's not truly static. I guess I will try seeing if the tube on the wing is not pointing in the direction of flight. I know many of the other aircraft I look at on the ramp and in the hangar have static sources on the outside of the fuselage between the firewall and the panel, so I thought that might help moving it there. The altimeter is usually reading about 70-100 feet low, but since I can see the ground whenever I fly it hasn't concerned me. Todd