A320
Flight Crew Last 90 Days 250; Flight Crew Total 10000; Flight Crew Type 5000
Troubleshooting
Aircraft Equipment Problem Critical
Flight Crew Overcame Equipment Problem; Flight Crew Took Evasive Action; Flight Crew Became Reoriented
Procedure; Aircraft; Company Policy
Lost nav capability on downwind ILS 34. IFR ceiling 500 FT visibility 1.5 miles. Went to STBY NAV Mode; manually tuned ILS's while on base. Got intercept vector. LOC did not engage; was still 15 miles out. Got re-vectored; did manual hand flown ILS. LOC was squirrelly. Uneventful landing. Got L/G SYSTEM DISAGREE ECAM during taxi in.
The Reporter stated that the Map display failed on both ND's even though the ND's appeared to continue normal operation. The event occurred in very busy Class B and he momentarily considered executing a missed approach but because of fuel considerations and a very knowledgeable efficient crew they were able to make the required manual navigation radio selections. The lack of automatic loc and glideslope lock-on surprised him. He felt that the Company training for this type event was inadequate and that he was ill prepared for all that transpired. A checklist of some sort for manual radio setup and flight procedures would help but following the checklist would certainly require a go around to get properly set up. The basic fact he will remember is there is no NAVAID auto tuning and the aircraft is flown raw data. After arrival; the aircraft was powered down and after re-powering; all systems returned to normal with no ECAM or other annunciations indicating what had happened.
While on approach vectors; an A320 Map function failed with operating ND's so the STBY NAV Mode was selected; the ILS tuned; and the approach flown raw data to a successful landing. The systems reset after the aircraft was powered down at the gate.