As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MKE - FLT 4106 - THE CREW REPORTED AFTER TAKEOFF, THE NOSE GEAR WOULD NOT RETRACT. THE AIRCRAFT RETURNED TO MKE WITHOUT FURTHER INCIDENT. MAINTENANCE REMOVED AND REPLACED THE NOSE GEAR UPLOCK BOX IAW EMB145 MM 32-33-07. OPERATIONAL CHECKS WERE GOOD IAW 32-34-00. THE AIRCRAFT WAS RELEASED FOR SERVICE. (M)