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Pilot Details

Age: 0 Weight: 0 Gender: Highest rating held at the time of the incident: Pilot experience level:

Gear Details

Wing Brand: Model: Mac Para Pasha II 42m Size: Paramotor Frame: Fly Products Power Gold 115 with Fly Products tandem “Flash” trike. + 280lb combined pilot & passenger weight with

Incident Details

January 1, 2006 Location of the incident: , Type of Incident:

Following full pre-flight, uneventful tandem launch and approx 20 minutes of flying time:

While flying with my tandem passenger at approximately 50′ AGL over desert covered with patches of cactus and ground cover, I reduce throttle to a slow descent and asked my tandem passenger if she would like to fly higher. After positive response from passenger, I applied 3/4 throttle to climb.

Almost immediately, we started to descend and I could hear the motor running at full RPM. I released the throttle fully, no change in engine RPM, then pumped throttle 2 times to see if cable had jammed, no change in engine RPM.

We began normal unpowered descent toward ground and fortunately I was able to avoid collision with cactus and ground shrubs which covered the ground below, and landed relatively softly, with no damage to passenger, pilot or equipment. I instructed the passenger to quickly exit the front of the trike, as I could hear the motor running at full RPM behind my head, and did not know what to expect. I immediately pressed and held the engine kill switch – no change. I got out of my harness and went to the back of the PPG to inspect the motor. The propeller was gone.

A fellow PPG pilot flying beside us, saw the emergency landing and landed himself, and immediately rushed over to assist. We both pulled the spark plug wire, but the engine kept going at full RPM. I then closed the fuel shut-off valve. It took approximately another 5 mins for the engine to stop due to lack of fuel, by which time the motor was smoking with significant heat rising from the cylinder head.

On inspection of the motor once stopped, we found that all 6 of the propeller bolts had sheared off, with portions of the bolts filling all six holes. I recovered the propeller about 100ft behind where we landed. The propeller was in tact, with burn marks at the hub and all bolts were gone. The tips were damaged from the rotation while hitting the ground from the height where the propeller left the PPG.

2nd pilot could not re-launch to fly back to our vehicles due to lack of launch space and 0 mph wind by this time. We left equipment in the desert and hiked approx 2 miles back to the vehicles, where we then returned to the equipment, loaded and left the area. The motor is now seized, with considerable heat damage to all components. Will have to buy a new motor as safety risk of repair when engine was so badly stressed is unacceptable.

Lessons learned: If your instructor never informed you about the possibility of such events, ask them to explain the possibility of such events occurring with your equipment, and how to deal with it in a safe manner, without the loss of expensive equipment or jeopardizing your safety if it does. My original dealer supplied bolts were secured and checked in the manner taught by my instructor, to a new propeller supplied by the dealer. I would suggest periodically replacing all propeller bolts, even if your old ones seem fine and you are not told to replace them. Check with your product manufacturer if there are any circumstances under which your 2-stroke PPG engine could go to full RPM without any pilot input, and not be shut down safely in flight. I am not aware of any circumstances where it is assumed normal to expect a 2 stroke motor to suddenly and uncontrollably go to max RPM and not be stopped by any method safely available to a pilot in flight. Hopefully others can learn from my experience.

This incident could have been far worse. In the event the propeller had remained on the motor, we would have kept climbing at full power until the fuel ran out (approx 2 hrs). In the event such a situation were to happen to anyone else, as an ASC certified BFI, I recommend either of the following options: 1. steeply turn the glider in one direction to maintain or decrease altitude, until the fuel runs out. 2. Commence a hard spiral dive with enough G force to starve the fuel supply to the engine and the engine should stall (can be very dangerous).

Ed note: There are other methods to deal with the possibility of a stuck throttle above cruise power. Many motors will continue to run even when heavily loaded (as in a 4G spiral), check with your instructor. Thanks to this pilot for sharing his experience.

Flight Window: Wind Speed: Type: Phase of Flight: Type of Injury: Collateral Damage: Analysis of the incident (additional input by the incident investigation team): Photos (if available):

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