Pilot's tip of the week

Surprise Propeller Motion

Featuring David Gagliardi

Subscriber question:

"What's something most pilots never think about but could be dangerous or deadly?" —Bobby K.

David:

“One day a while ago, I jumped into my airplane for a quick local flight and was shocked when I turned on the master—and the prop started turning. I shut off the master right away. Fortunately, nothing—and more importantly no one—was inside the prop arc.

This happened because the starter contactor (which can also be called the starter relay) had failed in the on position. Despite the fact that the airplane keys were still in my pocket, turning on the master powered the starter and the prop immediately started turning.

Because of this, I’ve added a ‘Prop area – CLEAR’ item before ‘Master – ON’ to my prestart check to ensure that if this happens again the possibilities of damage or injury are minimized.

Many of us have the essential ‘prop clear’ on a checklist right before turning the key, just like we have a check for oil pressure or ammeter not full scale immediately after engine start. However, few pilots think twice about turning the master on when they first open the plane to check fuel levels, deploy the flaps, or do any of several other preflight tasks. Don’t be one of those pilots. Any time you energize a system, ensure people and objects are out of harm’s way.”

How much caution do you exercise with people around a propeller?

(NEW) VFR Mastery scenario #97 “Keeping Your Cool at Hot Springs” is now available. Two years ago, you bought a 172M with a 180 HP conversion a bit past TBO. After 100 hours you decided to overhaul, and added an engine monitor. That revealed consistently high CHTs, often hitting 430°F in the climb. Today you’re at Hot Springs, SD, with the family. It’s 85°F with density altitude near 6000′. You know that if you lean for best power the engine will get super hot. Maybe that’s fine for a short time. Or maybe keeping things cool matters more, and a full rich takeoff is safer as long as performance is adequate. Or is there a middle ground? If you wait for cooler weather, it’ll be awhile. Watch the Intro video.

Get the Pilot’s Tip of the Week

Sign up here to receive tips like this every week along with videos, quizzes and more.

  • This field is for validation purposes and should be left unchanged.