Narrative:

While on approach to runway 27 at san we got an indication of an unreliable localizer. While trying to resolve this situation we got distraction and descended below approach altitude. We were alerted by the tower and immediately took corrective action and returned to the proper altitude. We were in VFR conditions at the time of the incident and the localizer problem had resolved itself. We continued the approach and landed. While we were never in any unsafe condition, we did allow an 'unreliable localizer' situation to distract us from our altitude control. A better solution would have been to break off the approach and resolve the localizer problem and then return for another approach.

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Original NASA ASRS Text

Title: FLC OF AN LGT DSNDED BELOW THE PUBLISHED APCH ALT DUE TO A DISTR CAUSED BY AN ERRATIC LOC INDICATION. TWR INTERVENED AND ADVISED THEM OF THEIR LOW ALT.

Narrative: WHILE ON APCH TO RWY 27 AT SAN WE GOT AN INDICATION OF AN UNRELIABLE LOC. WHILE TRYING TO RESOLVE THIS SIT WE GOT DISTR AND DSNDED BELOW APCH ALT. WE WERE ALERTED BY THE TWR AND IMMEDIATELY TOOK CORRECTIVE ACTION AND RETURNED TO THE PROPER ALT. WE WERE IN VFR CONDITIONS AT THE TIME OF THE INCIDENT AND THE LOC PROB HAD RESOLVED ITSELF. WE CONTINUED THE APCH AND LANDED. WHILE WE WERE NEVER IN ANY UNSAFE CONDITION, WE DID ALLOW AN 'UNRELIABLE LOC' SIT TO DISTRACT US FROM OUR ALT CTL. A BETTER SOLUTION WOULD HAVE BEEN TO BREAK OFF THE APCH AND RESOLVE THE LOC PROB AND THEN RETURN FOR ANOTHER APCH.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.