Narrative:

I cleared aircraft for the ILS runway 11 approach at sbp and switched him 9 NM from the field. The mode C indicated a descent below the crossing altitude at dobra. I called the tower on the shout line (which has been malfunctioning for 3 days). The tower did not acknowledge my safety alert. I issued it again over the shout line to no avail. The aircraft then descended below my radar coverage completely; at 5 NM final. The tower finally noticed the line blinking (shout function OTS) and issued the safety alert in an untimely manner.

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Original NASA ASRS Text

Title: SBA CTLR DESCRIBED FAILED MSAW NOTIFICATION EVENT WITH SBP TWR BECAUSE OF RECURRING LAND LINE FAILURES BTWN THE 2 FACILITIES.

Narrative: I CLRED ACFT FOR THE ILS RWY 11 APCH AT SBP AND SWITCHED HIM 9 NM FROM THE FIELD. THE MODE C INDICATED A DSCNT BELOW THE XING ALT AT DOBRA. I CALLED THE TWR ON THE SHOUT LINE (WHICH HAS BEEN MALFUNCTIONING FOR 3 DAYS). THE TWR DID NOT ACKNOWLEDGE MY SAFETY ALERT. I ISSUED IT AGAIN OVER THE SHOUT LINE TO NO AVAIL. THE ACFT THEN DSNDED BELOW MY RADAR COVERAGE COMPLETELY; AT 5 NM FINAL. THE TWR FINALLY NOTICED THE LINE BLINKING (SHOUT FUNCTION OTS) AND ISSUED THE SAFETY ALERT IN AN UNTIMELY MANNER.

Data retrieved from NASA's ASRS site as of May 2009 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.