What was found
CONDUCTED AUTOLAND HGS RUNWAY 16R KSEA CALM WINDS, 2 DEG C. APPROACH PROCEEDED NORMALLY UNTIL THE FLARE PORTION WHEN AIRCRAFT DRIFTED LEFT 20-30 FT. HGS SEEMED GOOD, JUST AUTOLAND DRIFT LEFT IN FLARE = UNSUCCESSFUL AUTOLAND. GROUNDED - YES. ACCOMP HGS LAST FLT FAULTS NO FAULTS & NO EXISTING FAULTS. FOUND OPC SOFTWEAR OUT OF DATE. LOADED UPDATED OPS 340B-FLD-C01-77 SOFTWARE. ACCOMP HGS SYSTEM TEST, TEST PASS REF HGS 4000 SMM 34-36-00. ACCOMP DFCS FLT FAULT REVIEW NO LAST LEG FAULTS. ACCOMP LAND VERIFY TEST, TEST PASS REF.B737-900 AMM 22-11-00-700-801.