What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(.4) About 30 minutes after takeoff, the pilot felt a 'buzz,' which lasted approximately 2 seconds. The airplane then shook violently, so the pilot retarded the throttle to reduce the shaking. He then turned the magnetos off, one at a time, and reapplied power, but the shaking returned with each power application. Carburetor heat was also applied, with no effect. The pilot then tried to add enough power to maintain altitude, but still found that its application resulted in violent shaking. Power was again reduced to keep the airplane controllable. The pilot attempted to guide the airplane to a nearby airport, but could not hold altitude, and headed for a plowed field. He tried to align the airplane with the furrows, but was unable to due to the approach angle. Upon touchdown, the landing gear collapsed, and the wing spars were damaged. During post-flight examination, part of one of the wooden propeller blades was found to be missing. There was no evidence of a bird strike. The propeller had been bolted onto the hub with the correct torque's, and the cowling had been found securely fastened to the airframe. The engine was also examined, with no significant anomalies note d, and there was no indication of airframe flutter. (-23) no narrative.
As the FAA filed it
(.4) ABOUT 30 MINUTES AFTER TAKEOFF, THE PILOT FELT A 'BUZZ,' WHICH LASTED APPROXIMATELY 2 SECONDS. THE AIRPLANE THEN SHOOK VIOLENTLY, SO THE PILOT RETARDED THE THROTTLE TO REDUCE THE SHAKING. HE THEN TURNED THE MAGNETOS OFF, ONE AT A TIME, AND REAPPLIED POWER, BUT THE SHAKING RETURNED WITH EACH POWER APPLICATION. CARBURETOR HEAT WAS ALSO APPLIED, WITH NO EFFECT. THE PILOT THEN TRIED TO ADD ENOUGH POWER TO MAINTAIN ALTITUDE, BUT STILL FOUND THAT ITS APPLICATION RESULTED IN VIOLENT SHAKING. POWER WAS AGAIN REDUCED TO KEEP THE AIRPLANE CONTROLLABLE. THE PILOT ATTEMPTED TO GUIDE THE AIRPLANE TO A NEARBY AIRPORT, BUT COULD NOT HOLD ALTITUDE, AND HEADED FOR A PLOWED FIELD. HE TRIED TO ALIGN THE AIRPLANE WITH THE FURROWS, BUT WAS UNABLE TO DUE TO THE APPROACH ANGLE. UPON TOUCHDOWN, THE LANDING GEAR COLLAPSED, AND THE WING SPARS WERE DAMAGED. DURING POST-FLIGHT EXAMINATION, PART OF ONE OF THE WOODEN PROPELLER BLADES WAS FOUND TO BE MISSING. THERE WAS NO EVIDENCE OF A BIRD STRIKE. THE PROPELLER HAD BEEN BOLTED ONTO THE HUB WITH THE CORRECT TORQUE'S, AND THE COWLING HAD BEEN FOUND SECURELY FASTENED TO THE AIRFRAME. THE ENGINE WAS ALSO EXAMINED, WITH NO SIGNIFICANT ANOMALIES NOTE D, AND THERE WAS NO INDICATION OF AIRFRAME FLUTTER. (-23) NO NARRATIVE.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.