As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
30 KNOT SPLIT ON AIRSPEED AND 1000 SPLIT ON ALTIMETERS CLIMBING THROUGH FL 310, SPLITS ON BOTH WERE INCREASING, BOTH HIGH ON F/O SIDE. SECURED LOOSE B NUT IN CEILING OF AIRCRAFT BELLY. ACCOMPLISHED PITOT-STATIC CHECK. OPS AND LEAK CHECK ED NORMAL IAW MM 34-12-0.