Static port location- One Design DR-107

Hello all, Moving my static ports from the builders location of just behind the trailing edge of the wing root, to something closer to the plans location. I'm having a problem of a bouncy altimeter and switching the altimeter out for another didn't fix the problem. It has been suggested by someone more competent than I that we put them at STA 88 (per the plans), however, but put them down underneath the fuselage on the 45deg. section of the belly, one port each side vs. on the turtle deck area (per the plans). The location will keep them hidden from view and be easy to install. I'm concerned of pulses from the exhaust affecting it, any thoughts? Piper apparently did this on the PA20/22 series with good results. Thanks, Russell

I will suggest that the PA-20 and -22 are high wing airplanes so putting the static ports lower moves them away from the airflow behind the wings and flaps.

The 1D is a low wing configuration. Putting the static ports low on the fuselage moves them into the flow behind the wing, exactly what you do not want. Higher on the fuselage is better.

Dan Rihn might have done a bit of flight testing to come up with the plans location for the static ports. It is a little bit of trial and error to get a good static port location. You might e-mail him and ask or post on the 1D forum.

Piper solved the problem of figuring out a good static port location by combining the pitot and static ports on their under wing "knife blade". Other manufacturers use a combination pitot-static boom mounted through the leading edge of the wing. My Pitts uses that setup and the Skybolts use that setup. The nice folks at Steen Aerolab would be happy to sell you this part - https://secure.steenaero.com/Store/s...68CF89D388401B

Best of luck,

Wes
N78PS