Narrative:

On may/xa/98, a dangerous incident occurred at ZOA. Area a was holding 19 aircraft destined for sfo. 9 aircraft at sector 12 (low altitude), and 10 aircraft at sector 14 (high altitude). There was no flow control program in place at the time, nor did anyone put one in place after bad WX moved in the san francisco bay area. The sector 12 controller had 2 hours and 10 mins on position while holding 9 aircraft with no relief in sight because of staffing shortages. The sector 14 controller had 2 hours and 15 mins on position while holding 10 aircraft, also with no relief in sight. This incident occurred between XF15 and XH35. Both controllers were due to end their shift at XH30, meaning they had already worked 8 and 9 hours, were fatigued and waiting to be relieved. Combine working a full shift, holding 9 or 10 aircraft at the end of it, a fatigued controller, and you have a recipe for a terrible accident or incident. Compounding this situation was 7 out of the 19 aircraft had to divert to oak due to fuel considerations. This, in turn, made sector 11 very busy with these diversions mixing with their normal oak arrival rush from the south, and their normal routine traffic, requiring 2 controllers, thereby reducing staffing even more. This also made sector 13 extremely busy because of the saturation at sector 11, sector 13 was forced to start holding all oak arrs at the pxn VOR. Sector 13 was being worked by only one controller, again because of staffing shortages. In all that evening, area a was working 1 controller below established guidelines, with no overtime called in. 4 controllers were required to work very heavy volumes of traffic while exceeding 2 hours on position, at or near the end of their shifts. This created a very unsafe condition, and a potential for a very dangerous accident occurring. First and foremost, staffing must be increased at ZOA. In plain language, we just do not have enough fpl's to staff for our guidelines. We routinely work below established guidelines, and supervisors are apprehensive to call in overtime. Secondly, this incident just cannot be blamed on an incorrect WX forecast. At XA15, the supervisors and traffic management received a forecast from the NWS indicating VFR WX. However, when the bad WX did move in at approximately XE30, no action was taken by tmu or supervision to preclude this situation from occurring. At shift start, area a was working 1 controller below established guidelines, and no overtime was called in. The supervisor in charge should have called in overtime to bring the area up to established guidelines. Also, the supervisor should have held over 3 controllers that went home at XG00. Finally, a 'flow control program' or 'ground stop' should have been initiated as soon as possible after the WX worsened to alleviate the heavy workload on the controllers already working shorthanded.

Related reports:

Google
 

Original NASA ASRS Text

Title: AN ARTCC RADAR CTLR AT ZOA CLAIMS THAT STAFFING WAS NOT SUFFICIENT TO HANDLE THE TFC AFTER WX UNEXPECTEDLY MOVED INTO THE AREA. SOME ACFT DIVERTED DUE TO LOW FUEL STATUS, AND SOME CTLRS WERE ON THE SECTOR MORE THAN 2 HRS WITHOUT RELIEF.

Narrative: ON MAY/XA/98, A DANGEROUS INCIDENT OCCURRED AT ZOA. AREA A WAS HOLDING 19 ACFT DESTINED FOR SFO. 9 ACFT AT SECTOR 12 (LOW ALT), AND 10 ACFT AT SECTOR 14 (HIGH ALT). THERE WAS NO FLOW CTL PROGRAM IN PLACE AT THE TIME, NOR DID ANYONE PUT ONE IN PLACE AFTER BAD WX MOVED IN THE SAN FRANCISCO BAY AREA. THE SECTOR 12 CTLR HAD 2 HRS AND 10 MINS ON POS WHILE HOLDING 9 ACFT WITH NO RELIEF IN SIGHT BECAUSE OF STAFFING SHORTAGES. THE SECTOR 14 CTLR HAD 2 HRS AND 15 MINS ON POS WHILE HOLDING 10 ACFT, ALSO WITH NO RELIEF IN SIGHT. THIS INCIDENT OCCURRED BTWN XF15 AND XH35. BOTH CTLRS WERE DUE TO END THEIR SHIFT AT XH30, MEANING THEY HAD ALREADY WORKED 8 AND 9 HRS, WERE FATIGUED AND WAITING TO BE RELIEVED. COMBINE WORKING A FULL SHIFT, HOLDING 9 OR 10 ACFT AT THE END OF IT, A FATIGUED CTLR, AND YOU HAVE A RECIPE FOR A TERRIBLE ACCIDENT OR INCIDENT. COMPOUNDING THIS SIT WAS 7 OUT OF THE 19 ACFT HAD TO DIVERT TO OAK DUE TO FUEL CONSIDERATIONS. THIS, IN TURN, MADE SECTOR 11 VERY BUSY WITH THESE DIVERSIONS MIXING WITH THEIR NORMAL OAK ARR RUSH FROM THE S, AND THEIR NORMAL ROUTINE TFC, REQUIRING 2 CTLRS, THEREBY REDUCING STAFFING EVEN MORE. THIS ALSO MADE SECTOR 13 EXTREMELY BUSY BECAUSE OF THE SATURATION AT SECTOR 11, SECTOR 13 WAS FORCED TO START HOLDING ALL OAK ARRS AT THE PXN VOR. SECTOR 13 WAS BEING WORKED BY ONLY ONE CTLR, AGAIN BECAUSE OF STAFFING SHORTAGES. IN ALL THAT EVENING, AREA A WAS WORKING 1 CTLR BELOW ESTABLISHED GUIDELINES, WITH NO OVERTIME CALLED IN. 4 CTLRS WERE REQUIRED TO WORK VERY HVY VOLUMES OF TFC WHILE EXCEEDING 2 HRS ON POS, AT OR NEAR THE END OF THEIR SHIFTS. THIS CREATED A VERY UNSAFE CONDITION, AND A POTENTIAL FOR A VERY DANGEROUS ACCIDENT OCCURRING. FIRST AND FOREMOST, STAFFING MUST BE INCREASED AT ZOA. IN PLAIN LANGUAGE, WE JUST DO NOT HAVE ENOUGH FPL'S TO STAFF FOR OUR GUIDELINES. WE ROUTINELY WORK BELOW ESTABLISHED GUIDELINES, AND SUPVRS ARE APPREHENSIVE TO CALL IN OVERTIME. SECONDLY, THIS INCIDENT JUST CANNOT BE BLAMED ON AN INCORRECT WX FORECAST. AT XA15, THE SUPVRS AND TFC MGMNT RECEIVED A FORECAST FROM THE NWS INDICATING VFR WX. HOWEVER, WHEN THE BAD WX DID MOVE IN AT APPROX XE30, NO ACTION WAS TAKEN BY TMU OR SUPERVISION TO PRECLUDE THIS SIT FROM OCCURRING. AT SHIFT START, AREA A WAS WORKING 1 CTLR BELOW ESTABLISHED GUIDELINES, AND NO OVERTIME WAS CALLED IN. THE SUPVR IN CHARGE SHOULD HAVE CALLED IN OVERTIME TO BRING THE AREA UP TO ESTABLISHED GUIDELINES. ALSO, THE SUPVR SHOULD HAVE HELD OVER 3 CTLRS THAT WENT HOME AT XG00. FINALLY, A 'FLOW CTL PROGRAM' OR 'GND STOP' SHOULD HAVE BEEN INITIATED ASAP AFTER THE WX WORSENED TO ALLEVIATE THE HVY WORKLOAD ON THE CTLRS ALREADY WORKING SHORTHANDED.

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.