I think, if it works fine and reliably without that ring on the other 5,500+ Coupes built, it should work just fine without the ring on Mitchell’s plane. The converse (or is it obverse) is also true. if it works fine and reliably with that ring, why change it. I think he should check his airspeed as recommended in earlier posts and if it is OK why mess with it. My pitot, by the way, doesn't look like his. it is basically just two tubes soldered together. His may be from another supplier and for some reason require the ring. The others I have seen with the ring actually were two separate tubes with the ring around one rather than a "shrouded" tube also JMHO. Bill
To: [EMAIL PROTECTED]; [EMAIL PROTECTED]: [EMAIL PROTECTED]: Wed, 7 May 2008 09:45:18 -0500Subject: RE: [ercoupe-tech] Pitot Tube Calibration Ring Bill, I’ve never seen that on any other Coupe. You say, “I have seen that configuration before on other (usually older) airplanes. I believe if it ain't broke, don't fix it.” But how many of those other planes had the static holes spaced evenly around a tube co-axial with the pitot tube, like the Coupe? I think, if it works fine and reliably without that ring on the other 5,500+ Coupes built, it should work just fine without the ring on Mitchell’s plane. And, look at the ring and the static holes! The airflow as the air whips past that ring will make an abnormally low pressure zone behind the ring. There may be turbulent flow causing fluctuations in the airspeed and altitude readings. As a wild guess, I’m wondering if Mitchell’s static line is properly connected to the static ports in the probe at all. Perhaps his static lines are just venting to the cockpit or somewhere inside the wing. Could you get valid readings at all with that ring in place? JMHO Ed Burkhead http://edburkhead.com/Ercoupe/index.htm East Peoria, Illinois ed -at- edburk???head.??com (remove the ? marks and change -at- to @) _________________________________________________________________ Windows Live SkyDrive lets you share files with faraway friends. http://www.windowslive.com/skydrive/overview.html?ocid=TXT_TAGLM_WL_Refresh_skydrive_052008
