Narrative:

I offered LR25 the localizer approach to runway 4, he accepted. Began vectoring to localizer and asked tower to switch localizer 4 on (and ILS runway 22 off). Localizer 4 would not stay on, kept going into alarm. Also about this time, I lost my mapper, so could not vector to any approach. Informed all aircraft, and began vectoring LR24 to hold with acrs. LR24 passed over airport and reported runway in sight and requested a contact approach. After coordinating with tower, I approved. I then asked tower to try turning ILS back on, and it also failed to come back up right away, but I did get my mapper back after about 3 mins. After approximately 15 mins, the visibility improved enough to offer the 2 remaining acrs visual approachs to runway 8R. (There is no instrument approach to runway 8R.) all subsequent arrs made successful visual approachs to runway 8R. The locs at this airport have been none too reliable lately when switching back and forth. The localizer to runway 4 has been reported flts within the past month for similar problems. Likewise the mapper unit. When I and the users needed them most, they failed! I was left with ARTS and radios, but nothing else, no way to vector for any kind of approach -- least of all an ASR! We need to treat any equipment anomalies as if they are needed for IFR WX conditions right now, and not assume that since the WX is generally good here, an occasional problem with this equipment is acceptable.

Related reports:

Google
 

Original NASA ASRS Text

Title: RPTR CLAIMS ILS AND RADAR EQUIP FAILS WHEN IT'S NEEDED THE MOST.

Narrative: I OFFERED LR25 THE LOC APCH TO RWY 4, HE ACCEPTED. BEGAN VECTORING TO LOC AND ASKED TWR TO SWITCH LOC 4 ON (AND ILS RWY 22 OFF). LOC 4 WOULD NOT STAY ON, KEPT GOING INTO ALARM. ALSO ABOUT THIS TIME, I LOST MY MAPPER, SO COULD NOT VECTOR TO ANY APCH. INFORMED ALL ACFT, AND BEGAN VECTORING LR24 TO HOLD WITH ACRS. LR24 PASSED OVER ARPT AND RPTED RWY IN SIGHT AND REQUESTED A CONTACT APCH. AFTER COORDINATING WITH TWR, I APPROVED. I THEN ASKED TWR TO TRY TURNING ILS BACK ON, AND IT ALSO FAILED TO COME BACK UP RIGHT AWAY, BUT I DID GET MY MAPPER BACK AFTER ABOUT 3 MINS. AFTER APPROX 15 MINS, THE VISIBILITY IMPROVED ENOUGH TO OFFER THE 2 REMAINING ACRS VISUAL APCHS TO RWY 8R. (THERE IS NO INST APCH TO RWY 8R.) ALL SUBSEQUENT ARRS MADE SUCCESSFUL VISUAL APCHS TO RWY 8R. THE LOCS AT THIS ARPT HAVE BEEN NONE TOO RELIABLE LATELY WHEN SWITCHING BACK AND FORTH. THE LOC TO RWY 4 HAS BEEN RPTED FLTS WITHIN THE PAST MONTH FOR SIMILAR PROBS. LIKEWISE THE MAPPER UNIT. WHEN I AND THE USERS NEEDED THEM MOST, THEY FAILED! I WAS LEFT WITH ARTS AND RADIOS, BUT NOTHING ELSE, NO WAY TO VECTOR FOR ANY KIND OF APCH -- LEAST OF ALL AN ASR! WE NEED TO TREAT ANY EQUIP ANOMALIES AS IF THEY ARE NEEDED FOR IFR WX CONDITIONS RIGHT NOW, AND NOT ASSUME THAT SINCE THE WX IS GENERALLY GOOD HERE, AN OCCASIONAL PROB WITH THIS EQUIP IS ACCEPTABLE.

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.