What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
Aircraft was being operated by pilot training center LLC on a part 61 pilot night training flight.
On the 5th landing for the night with the student pilot at the controls and flight instructor observing, the student pilot placed the aircraft down approximately 100FT past taxi way A1 on runway 9L.
CFI reported the landing was on the main gear first then on rollout the NLG collapsed.
Mechanic found the NLG draglink center attach bolt on the runway. After inspection found the bolt had failed just below the nut.
I inspected the bolt and found it separated at a possible shear point just below the nut area. In addition the bolt appears to indicate a single point overload failure with possible zero evidence of slow crack propagation or fatigue. It appears the bolt may have been fatigued by multiple landings due to the nature of pilot training environment.
Failed bolt was the correct bolt a NAS464P4 per the Piper parts catalog.
Inspected the landing gear drag links for additional damage and found the down lock may have secondary damage from the drag link center bolt failing.
Researched AD 80-12-03 and Piper service letter 678 which addressed the weak down lock. Found no evidence of the NLG down lock causing this incident.
AD 80-12-03 was accomplished and had been documented, confirmed by log book review and aircraft inspection.
As the FAA filed it
AIRCRAFT WAS BEING OPERATED BY PILOT TRAINING CENTER LLC ON A PART 61 PILOT NIGHT TRAINING FLIGHT.
ON THE 5TH LANDING FOR THE NIGHT WITH THE STUDENT PILOT AT THE CONTROLS AND FLIGHT INSTRUCTOR OBSERVING, THE STUDENT PILOT PLACED THE AIRCRAFT DOWN APPROXIMATELY 100FT PAST TAXI WAY A1 ON RUNWAY 9L.
CFI REPORTED THE LANDING WAS ON THE MAIN GEAR FIRST THEN ON ROLLOUT THE NLG COLLAPSED.
MECHANIC FOUND THE NLG DRAGLINK CENTER ATTACH BOLT ON THE RUNWAY. AFTER INSPECTION FOUND THE BOLT HAD FAILED JUST BELOW THE NUT.
I INSPECTED THE BOLT AND FOUND IT SEPARATED AT A POSSIBLE SHEAR POINT JUST BELOW THE NUT AREA. IN ADDITION THE BOLT APPEARS TO INDICATE A SINGLE POINT OVERLOAD FAILURE WITH POSSIBLE ZERO EVIDENCE OF SLOW CRACK PROPAGATION OR FATIGUE. IT APPEARS THE BOLT MAY HAVE BEEN FATIGUED BY MULTIPLE LANDINGS DUE TO THE NATURE OF PILOT TRAINING ENVIRONMENT.
FAILED BOLT WAS THE CORRECT BOLT A NAS464P4 PER THE PIPER PARTS CATALOG.
INSPECTED THE LANDING GEAR DRAG LINKS FOR ADDITIONAL DAMAGE AND FOUND THE DOWN LOCK MAY HAVE SECONDARY DAMAGE FROM THE DRAG LINK CENTER BOLT FAILING.
RESEARCHED AD 80-12-03 AND PIPER SERVICE LETTER 678 WHICH ADDRESSED THE WEAK DOWN LOCK. FOUND NO EVIDENCE OF THE NLG DOWN LOCK CAUSING THIS INCIDENT.
AD 80-12-03 WAS ACCOMPLISHED AND HAD BEEN DOCUMENTED, CONFIRMED BY LOG BOOK REVIEW AND AIRCRAFT INSPECTION.
Other reports on N2163F · 2
Matched to the same aircraft by N-number and date.