Ultralight
Flight Crew Private
Flight Crew Last 90 Days 15; Flight Crew Total 260; Flight Crew Type 40
Situational Awareness; Troubleshooting
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Other / Unknown
Aircraft Aircraft Damaged; Flight Crew Took Evasive Action; Flight Crew Diverted; Flight Crew Landed in Emergency Condition; General Maintenance Action
Manuals; Procedure
I was flying on a pleasure flight when the propeller bolts failed and the propeller departed the aircraft. I landed on a private road with no damage to anything on the ground and no further damage to the airplane.
The reporter stated that the wooden propeller was found intact. After examining the propeller and engine; the reporter and his Mechanic found no defects. They assumed that the bolts came loose which allowed the propeller to depart. The aircraft has been flown from a high humidity area to a very dry climate so the Mechanic suggested that the wood; which was last torqued in the humid environment; contained a high moisture content. After being in a dry environment for several months; the moisture left the wood allowing shrinkage. His Mechanic suggested re-torquing wooden propeller bolts following temperature changes; winter to summer; summer to winter and humid climate to dry and vise versa.
A Quad City Challenger Rotax Engine wooden propeller departed the aircraft inflight. The aircraft landed safely on a nearby road. The wooden propeller has not been re-torqued after being flown several months earlier from a high humidity area to a dry climate.