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  • @Georacer
    Thank you for your trust

    These topics deserve more than fast answers. Each addition or clarification are welcome.

  • @Jay, I think Jose's answers are much more educated than mine, so I'll leave it to what he said.

  • @Jay
    Sorry for the intrusion.
    Yes, varying inner diameters and tube length will affect measurements (nonstatic airspeed scenario)

    To treat the tube you have analytical models (including models validated against wind tunnel tests).
    Some air data equipment manual reports a delay per unit of length of piping

    Regarding the Pitot internals. That is harder. The loudspeaker(or similar) test will give you the dynamic response of the instrument.

  • @Georacer

    Ah ok. So then would varying inner diameters and tube length affect readings? I imagine so, but to what extent. The common digital airspeed sensor changes diameters twice (pitot tube ID -> flexible hosing ID -> board sensor ID)

  • Following Georacer reply

    Usually, the internal surface roughness is not a primary concern. Still, the internal tubing configuration is correlated to the dynamic performance of the instrument,


    Pushing the detail further, maybe too much :-). Regarding airflow within the pressure lines. Apart from the proper leaking. There are layouts that can sustain a small flow rate. For example, some low-pressure sensors (commercial units) generate a little flow in order to work. That leak can impact during static calibration of the assembled Pitot-Static unit.

  • Not my expertise, but I think the outside surface would be much more significant.

    Since there is no airflow inside the Pitot probe, just pressure buildup, the inside finish shouldn't matter. The outside would, on the other hand, at least up and a bit behind the static holes.

  • Quick question: would the inside surface of a pitot tube affect readings? For example, a printed pitot tube (depending on print orientation) would be rough from the layer resolution.

  • Developer

    On a calm day it should be possible to use GPS speed to calibrate the airspeed sensor, as long as the error is relatively linear.

  • @Marc  No kit available. Everything necessary to make your own Pitot should be available for free download on the website/Github. If is not the case let me know. Different people have made Pitots/ADCs.

    F.A.Q.
    Contribute User tested 3D printed parts from Shapeways. 3D Print Hardware Where to find the 3D print files? . STL, ready to 3D print files, are provi…
  • @ Georacer Thank you for your post!

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