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Hi everyone. Im trying to know how the magnetos work. Can anyone plz explain what happens when we push the starter of a GA airplane?(EX PA28,C172 etc)

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2 Answers



  1. Gary Moore on Oct 21, 2016

    Type “How magnetos work?” into any handy Internet search bar 🙂

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  2. Best Answer


    RachelAnn on Feb 02, 2017

    When you turn the ignition key the electrical(battery) starter is pushing a gear out to a gear on the prop. starting the rotation of the prop. After this first rotation the magneto’s can produce electricity by themselves, to furnish the spark to ignite the fuel. Therefore after the battery started rotation it is no longer needed.This is also the reason you can hand prop and aircraft, b/c all it needs to fly is an initial spin. A magneto is just a self contained generator producing electricity from rotating magnets……hope that helps. 🙂

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