PLT478: Starter
What code PLT478 covers, why the FAA tests it, and how to study Starter before your checkride.
Recall starter / ignition system - types / components / operating principles / characteristics
What this means for your checkride
The ignition system uses two engine-driven magnetos that make their own spark independent of the battery, firing two spark plugs per cylinder for redundancy and a more complete burn. The starter cranks the engine; the magnetos keep it running.
Because magnetos are self-powered and dual, they are tested for the redundancy they provide and for the mag-check that verifies each one.
Pilots think the magnetos need the battery. They are self-contained, which is why an engine keeps running after a total electrical failure, and why a hot mag is dangerous with the switch off.
Where to study it
A code on your test report is an area of deficiency. An authorized instructor must review it with you and endorse that review before you take the practical test, and the examiner may revisit it during the oral. Study it until you can explain it out loud, not just recognize the answer.