As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: FTER T/O THE LANDING GEAR HANDLE DID NOT GO UP. LOCK OVERRIDE DID NOT HELP. DECESION MADE TO DIVERT TO JFK, EMERGENCY DECLARED. ALL 3 GEAR REMAINED DOWN AND FIXED NORMAL WEIGHT LANDING AT JFK. MAINTENACE REPLACED NLG SEL/BYPASS VALVE I.A.W M/M 32-31-02.