← All explained questions · Supplemental · XII — Postflight Procedures
After parking at the FBO, the proper engine shutdown sequence (most piston aircraft) is
Choices
magnetos OFF, mixture cut-off, master OFF.
Magnetos-off-then-mixture leaves fuel in cylinders.
✓ set parking brake, throttle to idle, run engine at idle for 30-60 seconds.correct
allows turbo to spool down or just cools cylinders), MIXTURE to IDLE CUT-OFF (engine stops from fuel starvation, not by killing mags. leaves mags untimed), then magnetos OFF, master OFF. Standard shutdown: idle 30-60 sec to cool, MIXTURE TO CUT-OFF (engine starves of fuel and stops cleanly), then mags OFF, master OFF. Cutting mags with fuel still in cylinders means raw fuel remains — risk of accidental fire if engine 'ticks over' on a hot cylinder. Mixture-shutdown is the proper sequence per virtually all GA POHs.
magnetos OFF first to be safe.
Mags-off without mixture cutoff is the wrong sequence.
shut master off first to save battery.
Master off with engine running cuts electrical loads but not engine.
Why
allows turbo to spool down or just cools cylinders), MIXTURE to IDLE CUT-OFF (engine stops from fuel starvation, not by killing mags. leaves mags untimed), then magnetos OFF, master OFF. Standard shutdown: idle 30-60 sec to cool, MIXTURE TO CUT-OFF (engine starves of fuel and stops cleanly), then mags OFF, master OFF. Cutting mags with fuel still in cylinders means raw fuel remains — risk of accidental fire if engine 'ticks over' on a hot cylinder. Mixture-shutdown is the proper sequence per virtually all GA POHs.
FAA source: POH; POH Engine Shutdownbrowse the reference library →
Original study question written for this course — representative of FAA knowledge-test topics, not an actual current FAA exam question.