What was found
ON LANDING DCA, NOSE LANDING GEAR COLLAPSED. UPON ROTATION IN ORD, THE NOSE WHEEL ASSEMBLIES DEPARTED THE AXLE. AIRCRAFT LANDED ON THE AXLE IN DCA. CAUSE OF FAILURE WAS THE REPAIR SHAFT, UAL P/N 3F13178-2. IT WAS DETERMINED THAT THE REPAIR SHAFT THREADS WERE NOT MANUFACTURED PER THE UA DRAWING. THIS EVENT IS CURRENTLY SUBJECT TO NTSB INVESTIGATION NO. DCA03SA057. ALL UAL 737 AIRCRAFT NLG AXLES WERE INSPECTED FOR SIMILAR REPAIRS. SEVEN AIRCRAFT HAD THE REPAIR SHAFT REMOVED AND INSPECTED. ANY DISCREPANT SHAFTS WERE REPLACED.