As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE NLG ACTUATOR HAD IMPACT MARKS FROM THE LOCKING BALLS IN THE LOCKING CHANNEL. THESE IMPACT MARKS ALSO PUSHED PISTON MATERIAL OUT OF THE CHANNEL CAUSING INTERFERENCE WITH THE LOCKING SLEEVE. THIS INTERFERENCE CREATED METAL SHAVINGS THAT INTERFEERED WITH THE DOWN LOCK MECHANISM. (K)