The pilot and passenger planned on a short flight around the traffic pattern in an open-cockpit, light sport airplane.
Shortly after takeoff, as the pilot turned downwind, he heard a “crack,” and the engine started to vibrate and lose power. He applied power, but the engine did not respond. He turned sharply left and then tried to stop the turn and descend, but the airplane continued to turn and descend until it hit a ravine near St. Mary’s, Kansas. Both the pilot and passenger were seriously injured in the crash.
A witness saw two objects fall from the airplane shortly after the engine sound “stopped.”
Both objects were retrieved. The first was the passenger’s knitted hat, the top of which was “chewed up” and had a line burnt/melted into it. The other object was one of the propeller blades.
The accident is consistent with the passenger’s hat exiting the cockpit and impacting the three-bladed pusher propeller, which led to the separation of one of the propeller blades and the subsequent loss of engine power.
Probable cause: The loss of engine power due to a propeller failure when the passenger’s hat exited the cockpit and impacted the three-bladed pusher propeller, separating one of the propeller blades.
NTSB Identification: CEN18LA027
This November 2017 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
It is an Ultralight type aircraft, aluminum tubing with fabric covering, so it would not have used the types of propellers common to the GA fleet. Since they mention it was three bladed my guess is it was an IVO prop where the blades are retained by two bolts thru the section inside the hub. A strike by a heavy enough object could be enough to brake that hub attachment. A regular prop carved from laminated wood or cast from metal would be significantly stronger then that arrangement.
It has an N number and has an empty weight over 254 Lbs. So, not an ultralight. It’s constructed like a typical ultralight, but it would not qualify as one.
Sarah you are misinformed as to what defines an ULTRALIGHT… As for the Prop, Ive personally had things go through IVO props and can assure you this was NO Ivo………. IVOs are Solid carbon fiber with a Steel Rod core…… FYI there are many aircraft flying using carbon fiber props Some are Turban powered commercial passenger transports … They are Equally as strong as a Metal prop but with far less MOI… Pound for Pound CARBON FIBER is stronger than steel….. My guess this was probably a hollow foam core prop…. Possibly a POWERFIN…….. Here in the US we have THOUSANDS of Aircraft flying that are built using Aluminum tubing and Fabric which are NOT ultralights…. These materials are a popular materials of choice by many aircraft designers… My guess this was a LIGHT SPORT AIRCRAFT possibly a TRIKE given it was a pusher… Trikes are designed to withstand 6 Positive Gs… THAT equates to around 6000 pounds of force…. Very Strong……. Two people were on board this aircraft so that alone should have told you something about the TYPE of aircraft… Clearly to the informed this was no “ULTRALIGHT”
A knit hat caused a prop fail? I am very leery of birds now.
Who fly’s open cockpit with loose stuff? These two who may not live to tell about it.
Keep in mind it was an ultralight type aircraft so not much of a cockpit to begin with. The passenger was probably wearing that hat to stay warm and it got blown off. Maybe a roll of duct tape could have helped with headgear retention.