We’re given enormous freedom to risk our own necks—not others.

Our rules are written to lust us risk ourselves when we fly—we must work to keep it that way. Continued self regulation depends on it. The incidents below shows what’s possible and what’s at stake.

Exploding Prop

2016-Sept-14 I and many other onlookers watched as the pilot began his launch.

He started running, brought the wing up then throttled up. Soon after all hell broke loose as xploding propeller pieces shot out in all directions, including two pieces of the aluminum radial arm that caused it all.

Two things stick out. One piece hit a nearby paramotor, whose pilot was standing just beyond, with enough force to cut four pieces of cage netting. That would have been no good for anyone’s soft tissue. Second was a piece of aluminum that landed over a hundred feet away, also in the propeller disc plane. Of nearly equal interest was one piece of propeller that stuck itself over four inches into the ground near the pilot–deep enough that it was, apparently, hard to get out.

This happens periodically but this time John Stovall spent some effort to uncover what, how and where the biggest pieces went. It wasn’t a memorable failure, either, the aluminum arm apparently just came unscrewed rather than flexing into the prop.

We should use this as a reminder to consider where we do our runups and who we allow nearby during runups and launch. The danger zone is shown below.

The pilot whose machine was damaged adds:

The aluminum rod had enough force after tearing through my net to put a small dent on of the aluminum structural members of my Miniplane. It’s not large enough cause any structural issues, but it was a very sobering illustration of what it would have done to my kneecap which was on the opposite side of that motor. 

I’ve been giving it some thought, and while this has certainly encouraged my to be even more vigilant about prop safety in the future, it’s definitely an illustration of how you can’t really guarantee safety around a prop. 

For the most part, I took reasonable precautions, but they were compromised by what turned out in some ways to be worst case scenario. When I realized the pilot in question was about to take off I moved myself and my parameter back about 25-30 feet. This put my about ten feet forward of the spectator line, and while I should have move back the additional distance, I very much doubt that it would have made a big difference in the impact speed of the aluminum. I also took the precaution of standing well forward of the launch point so that I would be exposed to the disk of danger for the briefest possible period of time. 

I think the following three things contributed to this near miss:

The wind was parallel to the runway during this time. This is a worst case scenario, because it means that spectators can’t get far enough away from pilots to get out of the danger zone during takeoff. When winds are parallel to the runway, it might be worth advising pilots to take off as far side of the runway in order to maximize distance.

Maintenance; it was a surprising failure, and it was an easy item to miss. I don’t typically check if the rods supporting my net have come unscrewed, but I will now. At a crowded event, it may be worth an extra vigilant preflight check. 

Lastly; luck. There was no warning of the pilot slipping, and the wing was in good shape and was well out of the power band by the time the launching pilot crossed me. It just goes to show that a spinning prop can always be dangerous. It’s not just when the wing is getting pulled up or the launch is about the get blown.

Danger Zone

Danger Zone (from the PPG Bible)

Danger Zone

We must be mindful of our danger zone including those beside us or who we may be launching/landing nearby. Hitting someone is obviously the worst case, but ejected or falling parts is always a possibility especially since we sometimes get stuff out and there’s no floor on our aircraft.

PPG crashes into 2 on takeoff, seriously injuring 1

This story told by Mike, a witness who was there with his wife.

15 July 2006 On the USPPA incident database this doesn’t sound so bad. The detailed description below highlights what’s at stake and how our responsibility can never be minimized. We worry about losing sites after annoying people with our noise, try chopping their faces off.

I’ve seen and read of some appalling risks taken with other people’s lives. Continuing a launch, motor screaming, to within inches of or even hitting other people, doing stupid stunts with non-participants and other dangerous actions. We should collectively ratchet our tolerances to make sure we consider that unacceptable. It’s one thing when the parties are involved, quite another when they don’t know of the risks. Never mind the horror of injury/death, this is probably the steepest slope to extinction or regulation we could start down.

What Happened

Behind the brick patio is a 2 story public beach house with showers and toilets. Being the first Saturday of a 3-day weekend (Monday is Umi no hi or Sea Day) there were many people at the beachfront picnicking with BBQs and swimming.

The PPGers were there when we arrived around 11AM. PPG pilots had been using the open patio as a runway/takeoff point. Throughout the day, the PPGs were taking off and flying overhead and along the beachfront coastline on short flights. There was as few as one and as many as 4, all using the patio and beach as a take off point. Being the first time I had seen PPGs take off and land, I was impressed at how quickly they could get off the ground.

At the time of the incident, there were three PPGs in the area, 2 stationary and one taking off.  There was a light breeze coming from the South. The windsock showed wind direction remained fairly constant all day. 

The PPG pilot attempted takeoff from the grass area, about 35 – 40 meters in front of people on the sand. He got a few feet (4-5?) off the ground and then quickly lost altitude near the concrete wave break dragging his feet on the ground – under power went straight into a group of 4. First hit was a young man (bumped to the side) the PPG continued forward under power crashing through the coolers and an umbrella set up. The young woman was struck.  I saw the woman knocked back off her feet. At this point, the wing fell from the sky and blocked my view. When the wing had come to rest on the sand, I saw the woman again, her right arm convulsing. I was about 40 feet away, on her left. I ran to see if I could help and saw that the prop had cut the right side of her face. The right side of her face was open – like a book. I yelled for my wife Marina (an M.D.) to help. 

I have had quite a bit of First Aid training but the extent of the injury was quite shocking. I did not know here to begin, massive injuries, extensive bleeding, her face appeared to be coming apart. My wife and I began first aid. She was unconscious and we could not find a pulse. The engine had stopped. The PPG pilot was sitting in the sand, strapped to the power unit staring at the young woman. The wood propeller had damage at both ends.

My wife applied direct pressure holding the face together, I yelled to others who had gathered, to call an ambulance. She began vomiting blood. I got a pulse and held her hands telling her she would be all right. With the bleeding controlled, she seemed to regain consciousness. She moved her head to the side (her neck was OK!) and coughed. Ice was applied and we waited for the ambulance.

The woman was taken by helicopter to Aichi Medical University Hospital in Nagoya–we are in communication with the doctors at the hospital, at this point she has lost an eye, many teeth, cut tongue and palate, the sinus cavity seems to have cushioned the brain. She will undergo a second surgery Thursday to reconstruct her cheekbones.

In some ways, she was lucky, a few millimeters up, down or to the left and things might have been much worse. 

Site of PPG Prop Strike Accident