1. Mick West

    Mick West Administrator Staff Member

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  2. Trailspotter

    Trailspotter Senior Member

    This plane (N569JB) is nearly 13 years old and your observation is similar to one that I posted earlier:

    I have since recalled an old explanation by @MikeC in a Contrail Science thread that probably applies to both cases:
    I think these observation of asymmetric contrails are not unique or rare. They may well be fairly common for older planes when the conditions for contrail formation are marginal. We just need to pay more attention to the engine contrails in such conditions.
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  3. Mick West

    Mick West Administrator Staff Member

    I agree. The shadowing explanation did not really seem to fit, even though the sun was perpendicular to the trial, it was probably far too high.

    If a plane needs more fuel to get the same thrust, then the exhaust is going to have a higher water content, and would either have to be hotter, or have more incomplete combustion.