4 ms·

In a turn, AOA will differ from one side of the plane to the other. You'd really need six AoA sensors, three per side, to be really confident.

CydeWeys 8y ago
Why would it differ from one side to the other? The wings are attached; they can't face differently into the wind from each other.
- outworlder 8y ago
  Aircraft will also be banking in a turn, so aerodynamic forces will be different, which is what the AoA sensor relies on. So they are right. I'm wondering how big of a difference it is. In other words, would a comparison with some epsilon factor be enough?
  - deleted 8y ago
    [deleted]
  - CydeWeys 8y ago
    There's not just two AoAs though, one per wing; there's a whole gradient of different AoA values going down both wings, like how the speed of a turning record is continuously variable from the inner to outer edge. It helps to think of the two wings combined into a single long wing (like a B2 bomber, which does actually have this design), then imagine that banking into a turn -- it's different values along the entire surface. A single AoA value taken from the center of this long combined wing, i.e. the fuselage in a typical jetliner configuration, should be sufficient for the purposes of determining if the plane is about to stall. If you really need the AoA values at all points along the wings, you can calculate them by combining the center AoA sensor with the roll angle. This logic applies to airspeed as well (it varies continuously along the entire wing surface when the airplane is banked into a turn), and note that airplanes only have one cluster of pitot tubes, which are located on the fuselage.
    - ams6110 8y ago
      That does seem to make sense. Thanks for the explanation.
- ams6110 8y ago
  They would be close in general I guess, but possibly differ in maneuvers with banking and yaw? Perhaps some comparisons of averages over time would be best, rather than reacting to instantaneous disagreement. (Not an aeronautical engineer ... see for example description of turning stalls at https://www.experimentalaircraft.info/flight-planning/aircraft-stall-effect.php https://www.experimentalaircraft.info/flight-planning/aircra... ).
outworlder 8y ago
Is the difference in airflow between two wings big enough to matter? Genuine question, I don't know.

CydeWeys 8y ago

Why would it differ from one side to the other? The wings are attached; they can't face differently into the wind from each other.

outworlder 8y ago
Aircraft will also be banking in a turn, so aerodynamic forces will be different, which is what the AoA sensor relies on. So they are right. I'm wondering how big of a difference it is. In other words, would a comparison with some epsilon factor be enough?
- deleted 8y ago
  [deleted]
- CydeWeys 8y ago
  There's not just two AoAs though, one per wing; there's a whole gradient of different AoA values going down both wings, like how the speed of a turning record is continuously variable from the inner to outer edge. It helps to think of the two wings combined into a single long wing (like a B2 bomber, which does actually have this design), then imagine that banking into a turn -- it's different values along the entire surface. A single AoA value taken from the center of this long combined wing, i.e. the fuselage in a typical jetliner configuration, should be sufficient for the purposes of determining if the plane is about to stall. If you really need the AoA values at all points along the wings, you can calculate them by combining the center AoA sensor with the roll angle. This logic applies to airspeed as well (it varies continuously along the entire wing surface when the airplane is banked into a turn), and note that airplanes only have one cluster of pitot tubes, which are located on the fuselage.
  - ams6110 8y ago
    That does seem to make sense. Thanks for the explanation.
ams6110 8y ago
They would be close in general I guess, but possibly differ in maneuvers with banking and yaw? Perhaps some comparisons of averages over time would be best, rather than reacting to instantaneous disagreement. (Not an aeronautical engineer ... see for example description of turning stalls at https://www.experimentalaircraft.info/flight-planning/aircraft-stall-effect.php https://www.experimentalaircraft.info/flight-planning/aircra... ).

outworlder 8y ago

Is the difference in airflow between two wings big enough to matter? Genuine question, I don't know.