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Forgive the this topic placement as it might be similar to other older ones (Although I a bit sure that the main contents might be different than other older ones). In the upcoming days I will have a very important interview to a position I am interested as it is involved around a passion of mine. I would like to gain some insights in the following topics (any research paper, final thesis, or other explanatory material is more than welcome).

  • Pitot and static sensors placement. How do we choose the most ideal position on an aircraft's structure to place these sensors? What do we need to take into consideration apart from document standards?
  • Definition of air data related measurement points and routing of pressure tubes involved. Calibration of air data systems.

Any help is much appreciated,
Thanks in advance.

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  • $\begingroup$ Welcome to aviation.stackexchange! $\endgroup$
    – DeltaLima ♦
    Commented Jan 13, 2023 at 14:20
  • $\begingroup$ Welcome! As for the placement I bet (hence no answer) it's mostly based on experience. The calibration is obviously done according to test flight data. $\endgroup$
    – Jpe61
    Commented Jan 13, 2023 at 15:09
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    $\begingroup$ Potential duplicate: aviation.stackexchange.com/questions/56631/… $\endgroup$
    – Gerry
    Commented Jan 14, 2023 at 18:14

2 Answers 2

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Both the pitot and static pressures will vary a lot based on:

  • Airspeed
  • CG location
  • Angle of bank
  • Angle of attack
  • Configuration, especially flaps

In the CFD model, and then again in flight test, you are looking for a placement that generates the least variation in calibration error over the greatest range of conditions.

No matter where you place them, you are going to calibrate the instrument to correct for the physical limitations of the measurement system. So you don't care how large the calibration error is, you care much more about how consistent it is.

Designers, by necessity, accept a lot of calibration error in the pitot (airspeed) system and publish various speed in KIAS to accomodate that. But the static port drives altimetry and really needs to be placed where static pressure remains the most consistent across a wide range of attitudes and configurations.

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You put the pitot inlet so its tip protrudes into the free stream air, outside of the boundary layer flow and normal to the direction of travel.

The static port inlet is positioned flush to the fuselage surface so a pressure reading taken from it is exactly equal to the existing ambient pressure at zero velocity. The easiest way to do that is by experiment.

(an aside: a friend who homebuilt a Rutan Q2 claimed he got a 250 MPH cruise on an O-200 engine. I told him, "yeah, and if you let ME locate your static port, I could get you 300!")

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