As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE NLG WOULD NOT RETRACT AFTER TAKEOFF FROM IAH. THE NOSE GEAR UNSAFE LIGHT REMAINED ILLUMINATED. THE AIRCRAFT WAS RETURNED TO IAH WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND THE NOSE GEAR STRUT REQUIRED SERVICING. A FULL NOSE STRUT SERVICING WAS PERFORMED IAW MM 32-21-02. A NLG SWING WAS PERFORMED AND OPERATION CHECKED GOOD.