how do you conduct a pitot-static test on an aircraft fitted with a venturi?

Discussion in 'Instruments / Avionics / Electrical System' started by Twodeaddogs, Oct 3, 2016.

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  1. Oct 3, 2016 #1

    Twodeaddogs

    Twodeaddogs

    Twodeaddogs

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    Hi all,
    I was asked to do a pitot-static test on a Pa-22 Colt, which has a venturi fitted, as well as a pitot-tube on the left wing and static ports under the belly. How do you do a leak test on this set-up? Do you block off the venture?

    regards
    TDD
     
  2. Oct 3, 2016 #2

    Marc Zeitlin

    Marc Zeitlin

    Marc Zeitlin

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    One assumes that the venturi is used to power the vacuum instruments, yes?

    If so, then it's not connected in any way to the pitot or static lines, which are only connected to the altimeter, VSI, airspeed indicator, and transponder altitude encoder. So just like you can ignore the seat rails when conducting a leak test on the pitot and static systems, you can ignore the venturi.

    Or am I missing something else?
     
  3. Oct 3, 2016 #3

    Toobuilder

    Toobuilder

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    Yep. The venturi is the "muscle" to drive gyros... It has nothing to do with the pitot/static system.
     
    Lucrum likes this.
  4. Oct 3, 2016 #4

    Turd Ferguson

    Turd Ferguson

    Turd Ferguson

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    +3, the venturi is irrelevant to a static test.
     
  5. Oct 3, 2016 #5

    fredoyster

    fredoyster

    fredoyster

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    Perhaps the correct response is to be *sure* that the venturi is not connected in any way to the pitot-static system, as it would surely give goofy readings if it were.
     

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