ZippyB

ZippyB's Activity

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   ZippyB added a post in a topic Lousy ending to a great day    30 Jul 2013

    
   If you do install a new static port, I'd install a three way valve in the static line while you check out your new  port. Then you can switch back and forth between the cabin and the new port.
    
   When I bought my Model IV, there was a static port installed on the boot cowl, but it wasn't hooked up.  Not long thereafter,  while I had the boot cowl off, I checked that the port was clear,  then reattached the static line.  On my next takeoff, I was fat, dumb and happy a few hundred feet in the air as I cleared the end of the runway.   When I pulled my eyes back in the cockpit for a quick instrument scan I nearly laid a brick - the VSI showed several hundred feet per minute DOWN. 
    
   After a few seconds of confusion laced with a pinch of terror, I realized what the problem was.  If the VSI was that much in error, so was the altimeter, and to a lesser extent, the airspeed.  But I couldn't reach the static line to pull it off the outside port.  So there I was in a plane I wasn't very familar with at an airport I also wasn't very familar with.  Boy, was I happy to get back on the ground that day.
    
   After that, I made a proper, if clunkly, hemisperical-nosed static probe and clamped it to the strut bracing.  Using a three way valve to switch between the probe and an open tube under the panel,  I decided there wasn't just much difference between the two.  (I didn't try that with the door open.)
    
   I've since removed the test probe, but am still considering permanently installing a hemispherical-nosed pitot-static probe.  Figuring out how to mount it and drilling another hole in the rear spar (for the static line) slow me down, though.
    
   Anybody else have an installed a pitot-static probe?
   

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