What was found
ON INITIAL CLIMB FMC SCRATCH PAD MESSAGE CHECK PO IRS/IRS RECEIVED. POSITION PAGE 3 SHOWS L IRS DRIFTED 7.3 MILES R IRS DRIFTED 4.3 MILES. GPS POSITION AND FMC SOLUTION 0.0. ACFT GROUNDED. DIVERSION TIME 16 MINUTES. ACCOMP'D FIM TASKS 34 21 NR 836 801AND 802. RADIAL POS ERR AND RES G/S WITHIN LIMITS. NO FAULTS LOGGED EITHER DFCS ADIRU'S HGS FMC'S. ADIRU'S CK OK REF LWMP CKLIST 22-00-01. HGS TEST AND DFCS TEST OK REF SAME. ACFT REMAINS CATIIIA A/L AND HGS QUAL.