What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
On November 28, 2022, N280JA, a Cessna 172S conducting routine pattern work at Ellington Field, TX (efd). During takeoff from runway 35L the right main brake caliper separated from the aircraft landing gear, traveled forward, and struck the propeller blades. One blade was dented slightly, and the other blade broke completely off 7 inches down from the tip. The pilot continued flight declared an emergency and made an uneventful landing 4 minutes later to runway 22.
On December 8, 2022, Houston FSDO inspectors travelled to privacy data omittedoperator privacy data omitted to conduct an investigation and gather written statements, evaluate maintenance records and take photos of the damaged right side main landing gear wheel/brake caliper and propeller. A logbook entry stated the last 100 hour inspection was performed 68 hours ago. The right main wheel brake liners were replaced during the last 100 hour inspection due to wear limits.
Prior to the incident, while taxiing to unload a passenger/instructor, the pilot mentioned in his statement that the nose wheel shimmy dampener was vibrating. Without shutting down the aircraft, the instructor visually checked for anomalies with the aircraft prior to departure.
During visual inspections of the aircraft on December 8, 2022, it was noted by Houston FSDO inspectors that the right-hand main wheel bearings, wheel half races and axle showed considerable wear damage. The right outboard brake caliper was recovered from the runway along with the separated piece of the propeller. The two-brake caliper liner attachment bolts sheared off in the threaded area and the brake caliper casting was damaged consistent with extreme force to attach bolt bores. The inner and outer brake caliper liners were not recovered. The right-hand brake disc showed evidence of wear and heat damage. The right brake disc wear was measured to be within limits with Cessna maintenance manual
Based off the available evidence, it appears the right-hand main wheel bearings failed. This caused enough play in the wheel to create a binding situation with the brake assembly and shearing the brake caliper liner bolts off allowing the brake caliper to depart the aircraft and strike the propeller. It could not be determined why the bearing failed.
In light of the pilot statement regarding a vibration felt in the landing gear during taxi just prior to the incident, recommend counseling on the benefits of detailed, precautionary inspections when unusual vibrations present prior to catastrophic failure.
As the FAA filed it
ON NOVEMBER 28, 2022, N280JA, A CESSNA 172S CONDUCTING ROUTINE PATTERN WORK AT ELLINGTON FIELD, TX (EFD). DURING TAKEOFF FROM RUNWAY 35L THE RIGHT MAIN BRAKE CALIPER SEPARATED FROM THE AIRCRAFT LANDING GEAR, TRAVELED FORWARD, AND STRUCK THE PROPELLER BLADES. ONE BLADE WAS DENTED SLIGHTLY, AND THE OTHER BLADE BROKE COMPLETELY OFF 7 INCHES DOWN FROM THE TIP. THE PILOT CONTINUED FLIGHT DECLARED AN EMERGENCY AND MADE AN UNEVENTFUL LANDING 4 MINUTES LATER TO RUNWAY 22.
ON DECEMBER 8, 2022, HOUSTON FSDO INSPECTORS TRAVELLED TO ^PRIVACY DATA OMITTED^OPERATOR ^PRIVACY DATA OMITTED^ TO CONDUCT AN INVESTIGATION AND GATHER WRITTEN STATEMENTS, EVALUATE MAINTENANCE RECORDS AND TAKE PHOTOS OF THE DAMAGED RIGHT SIDE MAIN LANDING GEAR WHEEL/BRAKE CALIPER AND PROPELLER. A LOGBOOK ENTRY STATED THE LAST 100 HOUR INSPECTION WAS PERFORMED 68 HOURS AGO. THE RIGHT MAIN WHEEL BRAKE LINERS WERE REPLACED DURING THE LAST 100 HOUR INSPECTION DUE TO WEAR LIMITS.
PRIOR TO THE INCIDENT, WHILE TAXIING TO UNLOAD A PASSENGER/INSTRUCTOR, THE PILOT MENTIONED IN HIS STATEMENT THAT THE NOSE WHEEL SHIMMY DAMPENER WAS VIBRATING. WITHOUT SHUTTING DOWN THE AIRCRAFT, THE INSTRUCTOR VISUALLY CHECKED FOR ANOMALIES WITH THE AIRCRAFT PRIOR TO DEPARTURE.
DURING VISUAL INSPECTIONS OF THE AIRCRAFT ON DECEMBER 8, 2022, IT WAS NOTED BY HOUSTON FSDO INSPECTORS THAT THE RIGHT-HAND MAIN WHEEL BEARINGS, WHEEL HALF RACES AND AXLE SHOWED CONSIDERABLE WEAR DAMAGE. THE RIGHT OUTBOARD BRAKE CALIPER WAS RECOVERED FROM THE RUNWAY ALONG WITH THE SEPARATED PIECE OF THE PROPELLER. THE TWO-BRAKE CALIPER LINER ATTACHMENT BOLTS SHEARED OFF IN THE THREADED AREA AND THE BRAKE CALIPER CASTING WAS DAMAGED CONSISTENT WITH EXTREME FORCE TO ATTACH BOLT BORES. THE INNER AND OUTER BRAKE CALIPER LINERS WERE NOT RECOVERED. THE RIGHT-HAND BRAKE DISC SHOWED EVIDENCE OF WEAR AND HEAT DAMAGE. THE RIGHT BRAKE DISC WEAR WAS MEASURED TO BE WITHIN LIMITS WITH CESSNA MAINTENANCE MANUAL
BASED OFF THE AVAILABLE EVIDENCE, IT APPEARS THE RIGHT-HAND MAIN WHEEL BEARINGS FAILED. THIS CAUSED ENOUGH PLAY IN THE WHEEL TO CREATE A BINDING SITUATION WITH THE BRAKE ASSEMBLY AND SHEARING THE BRAKE CALIPER LINER BOLTS OFF ALLOWING THE BRAKE CALIPER TO DEPART THE AIRCRAFT AND STRIKE THE PROPELLER. IT COULD NOT BE DETERMINED WHY THE BEARING FAILED.
IN LIGHT OF THE PILOT STATEMENT REGARDING A VIBRATION FELT IN THE LANDING GEAR DURING TAXI JUST PRIOR TO THE INCIDENT, RECOMMEND COUNSELING ON THE BENEFITS OF DETAILED, PRECAUTIONARY INSPECTIONS WHEN UNUSUAL VIBRATIONS PRESENT PRIOR TO CATASTROPHIC FAILURE.