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Does anyone know what units Drag Points are in?

1,850 Subsere  3 days ago

Does it translate at all? I assume it equals some measure of force, which, however, I cannot say.

Or, rather, I assume it's a multiplier. Something that scales in relation to airspeed, probably as some power or whatnot.

Anyone have a calculator of sorts?

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    24.4k BagelPlane

    Take a 1.5x1.5x1.5m cube in the designer. It has 2322 drag points. Coefficient of drag = 1.09 for a cube (NASA). Air density at sea level is 1.225 kg/m^3. With the assumption that drag points are in Newtons, use the drag force equation:
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    Fd = (0.5)(p)(v^2)(Cd)(A)
    2322 = (0.5)(1.225)(v^2)(1.09)(2.25), v = 39.3164 m/s
    .
    Repeat this with a 0.5x0.5x0.5 m cube (258 drag points):
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    258 = (0.5)(1.225)(v^2)(1.09)(0.25), v = 39.3164 m/s
    .
    Velocity holds constant for both situations. I assume this is the velocity and air pressure that the drag points are calculated with. Therefore, drag points would be in units of Newtons.

    2 days ago
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    24.4k BagelPlane

    I would assume newtons or kilonewtons given everything else is in SI units. However it's a fixed value, while drag force will change at speeds and attitude. Perhaps it is calculating drag force at a fixed speed and altitude for all aircraft, so that there is a common baseline of comparison across designs.

    2 days ago
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    41.3k Graingy

    This would be good to know tbh

    2 days ago
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    6,133 JBPAviation

    no
    all I know is it's directly proportional to SLOWNESS

    XD

    +1 2 days ago