As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAD-PHL - FLT NR 2229 - DURING TAKEOFF, RETURNED TO IAD DUE TO THE RIGHT MAIN GEAR INTRANSIT LIGHT REMAINING ILLUMINATED AFTER RETRACTION. AIRCRAFT LANDED AT IAD WITH NO FURTHER INCIDENTS. MAINTENANCE REPLACED THE UPLOCK SPRING. AIRCRAFT WAS RELEASED AND APPROVED FOR RETURN TO SERVICE. (M)