As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD - FLT 358 - AFTER TAKEOFF, NOSE GEAR WOULD NOT RETRACT. AIRCRAFT RETURNED TO ORD AND LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE FOUND NOSE GEAR STRUT UNDER INFLATED. SERVICED NOSE GEAR STRUT PER PROCEDURES. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)