As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON LANDING IN SGF NLG WOULD NOT LOCK DOWN WITH GEAR SELECTED DOWN. MANUAL EXTENSION PERFORMED WITH NO ISSUES. FERRIED AIRCRAFT. FOUND NLG STRUT LOW PRESSURE SIDE TO BE AT 0 PSI CAUSING THE NLG NOT TO EXTEND WITH WOW. THEN NLG WOULD INTERFERE WITH THE GEAR DOORS DURING EXTENSION. RESEALED NLG AND SERVICED, OPS CHECK OK.