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Why would you drain a fuel sump, and when

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When would you drain your fuel sump, and why?

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1 Answers



  1. ayavner on Aug 01, 2019

    Do you mean completely drain? Or just sampling? If just sampling, on the first flight of the day or after any refueling, or if it rains or you wash it and have reason to suspect water.

    If you mean completely drain – I guess if you suspect contamination/wrong fuel added, or you need to drain the tanks to get an accurate weight or you want to calibrate a fuel dipstick.

    BTW i have a handy acronym I give my students – COWS (moooo)
    Color – Odor – Water – Sediment.

    Did that answer your question?

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