Properly clear of the prop?

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by Phillip Zamagias

How many times have we been told ‘treat every propeller as if it is live’?

Like many things in aviation, years of doing repetitive tasks with no apparent danger can breed a familiarity that must never be allowed to overshadow good training.

Learning how to be a bush pilot in the Northern Territory, I was shown how to handle a propeller with due care. I was also shown how to ‘hand start’ an engine should the need ever arise. Good stuff!

Many years later, having never hand swung a prop to start an engine, or had an engine fire up unexpectedly, I came within a whisker of being ‘sliced and diced’.

While getting ready for an early departure from a remote bush airstrip, I began the very familiar routine of a daily inspection on my recently acquired plane. It was a near-new Piper 6XT with glass cockpit.

I had less than 100 hours on type, but more than 3500hrs on Cessna-206s, which had formed the mainstay of my bush flying career. The Piper brought with it a significant change in ergonomics that almost cost me dearly.

Not only were the cockpit instruments a radical departure from the F and G-model Cessna 206s I had traversed the country in, but the ignition switches were very different.

In single-engine Cessnas the ignition is operated by a key. On shutdown a pilot typically performs a magneto check before reducing the mixture control to idle cut-off. Once the engine has stopped, the key is rotated to the ‘ignition off’ position and the key is removed. Simple.

Having the keys in your pocket, especially when you are the sole pilot and away from home base, gives you a feeling of security. Of course, there is always the chance of a magneto going open-circuit and therefore being live. That’s why we are told to treat every propeller as live.

In the Piper, the ignition switches are conveniently located on the eyebrow panel above the pilot’s head. A proper shutdown check would ensure that the switches are in the ‘Off’ position after the engine is shut down.

I clearly missed that part of the checklist on shutdown and before starting the pre-flight for the next day’s trip. The friend I had been visiting came out to the airstrip and was filming my pre-flight in preparation for a close-up shot of takeoff.

What Richard saw shocked him almost as much as it did me.

As I checked the propeller’s leading edges for stone damage and pulled one blade through compression, the engine fired!

I felt the blade just graze my forearm and narrowly miss my head. Not enough to break any skin or leave a mark, but enough for me to feel the proximity of the blade.

My reaction is obvious from the video clip. I ran!

As this close call shows, every propeller can potentially bite. Treat every prop as if it’s live and stay well away whenever possible.

Read more about this close call at www.flightsafetyaustralia.com/2014/03/properly-clear-of-the-prop/

Video courtesy of Richard Davies.

Posted by Civil Aviation Safety Authority – CASA on Wednesday, January 6, 2016

I was surprisingly calm in the presence of my friend and the passenger who was coming with me on the next flight. I dismissed it with the calm detachment of a professional pilot and soldiered on.

Six years later I have given up flying and have been reflecting on that incident. I am submitting this article as a means of sharing what I learned that day.

Firstly, it can happen to you. Always maintain an attitude of vigilance and safety so that if (and when) something goes wrong, it doesn’t have to spell disaster.

Secondly, be extra careful when changing aircraft type, especially when changing manufacturers. Some basics carry over from model to model, but there are often significant differences in standard operating procedures across different brands of aircraft or engines. Take, for example, the use of fuel pumps in high-wing and low-wing aircraft.

Thirdly, no matter how comfortable you feel about your aeroplane, use checklists for shutdown and do a safety check before starting a pre-flight on an aeroplane. You might have missed something or, if it is a line aircraft, someone else might have left the switches in an unsafe position.

Finally, every propeller can potentially bite. Make sure you never have any body parts (or anyone else’s) in the arc of a propeller. Stand clear and be ready to jump away should the engine fire up.

I attribute my miraculous escape to the subliminal residue of the training I had received many years ago that just made me wary of any propeller.

However it was also something of a miracle that day.

Maybe God isn’t finished with me yet?

23 COMMENTS

    • Dito. Sadly, I think too much pride prevents a lot of safety discussions. Thanks for sharing the incident.

  1. Thanks for sharing. I know to treat a prop as if the magnetos are hot. But like you, have turned that prop many times over the years. It is easy to get complacent. Your sharing just reinforces a lesson learned many years ago, if you need to move the prop do it as if you are trying to start the engine, because it just may start. Being prepared is the first step to avoiding a preventable tragedy.

  2. Outstanding training aid! I just posted it on my page for my students to get a visual of what I preach. Thank you for sharing.

  3. Retired heavy jet captain.
    Started flying piston props, as we all do.
    The RAF taught me to treat props with great caution.
    This is a very worthwhile video and training advice!

  4. Don’t give up aviation, take a glider ride! No engine to fail, no fuel quantity worries and most of all, no fire.

  5. One thing you can do to be a little safer is rotate the prop backwards during your preflight. This way, the impulse coupling won’t fire, making it less likely for ignition to occur.

    • I’ve read rotating the prop backwards is bad for the vanes in a dry vacuum pump. Any other potential issues?

      • That’s absolutely correct from my memory of the PA32-300 or similar installation of HF Radio antennas! 🤔🙋‍♂️🧔

      • That’s absolutely correct Steve Allen from my memory of the PA32-300 or similar installation of HF Radio antennas! 🤔🙋‍♂️🧔

  6. What irritates me is the pilots that shout “Clear” or “Clear Prop” and immediately hit the starter. If you don’t give anyone time to get out of the way, you are wasting your breath and likely to kill or injure someone.

  7. Why did you pull the prop through in the first place? Its not in the preflight. With the Cessna type switch you make the mags hot when you engage the starter. With separate mag and starter switches you can crank the engine through with mags off. Really no need to pull the prop through by hand on a flat motor. Radial is a different story. Best practice on a flat motor is don’t touch the prop if you don’t need to.

    • Going back thru some old stories you raise a valid point, why? When I started out my instructor told me to pull the prop thru at least the same amount of times as there are cylinders to check compressions, I did it for a while but soon learnt that there really was no valid reason to do so. Again why? Well many years ago I was up in Broome & there was an old Catholic Bishop there (won’t mention his name but some will know who I mean) who had a C182 (latter a C210) & had to hand start it one day due a flat batt. Onboard where two sisters as in Nuns that where flying out to a mission, old mate swings prop, engines comes to life, he abruptly stands aside & the C182 moves fwd knocking old mate off his feet with the strut & the Cessna went on it’s merry way across the Broome airfield pilot-less, got damaged as did the poor hapless pax! Even though it was an intentional swing/start same dangers. True story, so I believe:-) Now I never do it, just check for prop nicks, that’s all. God is watching over me…lolol

    • I have flown with bush pilots quite a bit and the leading edge of the prop blades get nicks from gravel being sucked up. I have watched the pilots feel the edges and even gently file the any nicks smooth to prevent splitting or even shearing of the prop blade. I hope I have used the correct terminology. That is what I was told.

  8. First timer here. I had just changed the oil on my 1944-L4H the day before. I was on my way to an airshow and bright and early, pushed out and preflighted the old girl. Tied down and primed the engine, double check tail is tied, wheels are chocked and the throttle is cracked. Snap the prop through to distribute the prime in the spider, and off she goes! Scared the complacency out of me! Thankfully, I treat the prop as live even pulling it through. Turn out, the P lead of one of the mags came loose the day before when I was futzing around with the oil, and was laying for me.

    Remember- the gun is always loaded, the mags are always hot, and your wife will always find out!

  9. Hi Phil. you not flying a big loss to MAF, I remeber you from the “big Kangaroo” and Ballarat. Thanks for sharing.

  10. as an avionics L.A.M.E., I inspect the aircraft wiring on the checks. I have found on several occasions the grounding wire on the magneto holding on by ONE STRAND!. (it uses multistrand wire) If this grounding wire fails, you have a HOT MAG!. Subsequently, I always, without fail, even if not required, check that wire. If it is covered by a rubber boot, only takes a second to look, however, lots of these grounding wires are not covered by a rubber boot, and I have never found a worn wire under the rubber boot, as the boot acts as protection.

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