As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CRACKS HAVE BEEN FOUND ON THE REAR STABILIZER SPAR. SUSPECT CRACKS ARE CAUSED BY IMPROPER USE OF A RIVET SQUEEZER DURING FACTORY INSTALLATION. SUBMITTER STATED THESE CRACKS AND TOOLING MARKS HAVE BEEN FOUND ON 4 OTHER ASSEMBLIES. CRACKS RANGE IN SIZE FROM .25 INCH TO .50 INCH LONG, AND ARE FOUND ABOVE THE RIVET TAIL.