Narrative:

I was working a mid shift (XA00 to XI00). My area only staffs 2 controllers on this shift from XC00 to XH00. There was an area of thunderstorms in a line from omaha; northeast; extending south into kansas. This line continued to build during the night until reaching as far north as sioux city; ia. I worked from XB45 until XE30 without much impact to the area. When the other controller came in to relieve me; we looked at the monitor alert numbers (efficient sector loading numbers) and they were indicating that the sector was going to be yellow. I took a short break and returned to the area in 30 mins and the monitor alert numbers were now red indicating that the sector was going to exceed its safe sector capacity number. I proceeded to plug in on the radar associate position to assist the radar controller. By XG00 the line of thunderstorms had pushed north of sioux city; ia. The aircraft that normally fly over omaha; northeast; to points east; were now being forced to fly north around the area of thunderstorms. At the peak of the traffic load the radar controller had over 25 aircraft on frequency. The majority of these aircraft were deviating around the line of thunderstorms adding to the complexity of an already overloaded sector. This continued for nearly 1 hour. The monitor alert number for the sector is 15. During normal daytime operations this traffic load would never be allowed to be worked by 2 controllers. The sector that the radar controller and I worked that night can be broken up into 6 sectors during the day. The supervisor/omic took no action to assist us before or after the sector became saturated. In fact; he seemed unaware of our situation until well after the traffic had reached peak levels. Monitor alert numbers are dynamic numbers and should be adjusted downwards when sector efficiencies are reduced. An example of this would be when aircraft are deviating for WX. These alerts are also to be acknowledged and responded to when they occur by the supervisor/omic. This did not happen. 3 yrs ago; our manager arbitrarily reduced our staffing on the mid-shift from 3 controllers to 2. We believe that they were having trouble staffing the shifts during the day. If we would have had 3 controllers on this night it would have given us the ability to split the sector and have a radar associate float between the 2 sectors assisting either radar controller. This would have provided a more stable and workable situation.

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Original NASA ASRS Text

Title: ZMP CTLR VOICED CONCERN REGARDING MID NIGHT SHIFT STAFFING STANDARDS AND TFC VOLUME LEVELS EXPERIENCED BECAUSE OF SAME.

Narrative: I WAS WORKING A MID SHIFT (XA00 TO XI00). MY AREA ONLY STAFFS 2 CTLRS ON THIS SHIFT FROM XC00 TO XH00. THERE WAS AN AREA OF TSTMS IN A LINE FROM OMAHA; NE; EXTENDING S INTO KANSAS. THIS LINE CONTINUED TO BUILD DURING THE NIGHT UNTIL REACHING AS FAR N AS SIOUX CITY; IA. I WORKED FROM XB45 UNTIL XE30 WITHOUT MUCH IMPACT TO THE AREA. WHEN THE OTHER CTLR CAME IN TO RELIEVE ME; WE LOOKED AT THE MONITOR ALERT NUMBERS (EFFICIENT SECTOR LOADING NUMBERS) AND THEY WERE INDICATING THAT THE SECTOR WAS GOING TO BE YELLOW. I TOOK A SHORT BREAK AND RETURNED TO THE AREA IN 30 MINS AND THE MONITOR ALERT NUMBERS WERE NOW RED INDICATING THAT THE SECTOR WAS GOING TO EXCEED ITS SAFE SECTOR CAPACITY NUMBER. I PROCEEDED TO PLUG IN ON THE RADAR ASSOCIATE POS TO ASSIST THE RADAR CTLR. BY XG00 THE LINE OF TSTMS HAD PUSHED N OF SIOUX CITY; IA. THE ACFT THAT NORMALLY FLY OVER OMAHA; NE; TO POINTS E; WERE NOW BEING FORCED TO FLY N AROUND THE AREA OF TSTMS. AT THE PEAK OF THE TFC LOAD THE RADAR CTLR HAD OVER 25 ACFT ON FREQ. THE MAJORITY OF THESE ACFT WERE DEVIATING AROUND THE LINE OF TSTMS ADDING TO THE COMPLEXITY OF AN ALREADY OVERLOADED SECTOR. THIS CONTINUED FOR NEARLY 1 HR. THE MONITOR ALERT NUMBER FOR THE SECTOR IS 15. DURING NORMAL DAYTIME OPS THIS TFC LOAD WOULD NEVER BE ALLOWED TO BE WORKED BY 2 CTLRS. THE SECTOR THAT THE RADAR CTLR AND I WORKED THAT NIGHT CAN BE BROKEN UP INTO 6 SECTORS DURING THE DAY. THE SUPVR/OMIC TOOK NO ACTION TO ASSIST US BEFORE OR AFTER THE SECTOR BECAME SATURATED. IN FACT; HE SEEMED UNAWARE OF OUR SITUATION UNTIL WELL AFTER THE TFC HAD REACHED PEAK LEVELS. MONITOR ALERT NUMBERS ARE DYNAMIC NUMBERS AND SHOULD BE ADJUSTED DOWNWARDS WHEN SECTOR EFFICIENCIES ARE REDUCED. AN EXAMPLE OF THIS WOULD BE WHEN ACFT ARE DEVIATING FOR WX. THESE ALERTS ARE ALSO TO BE ACKNOWLEDGED AND RESPONDED TO WHEN THEY OCCUR BY THE SUPVR/OMIC. THIS DID NOT HAPPEN. 3 YRS AGO; OUR MGR ARBITRARILY REDUCED OUR STAFFING ON THE MID-SHIFT FROM 3 CTLRS TO 2. WE BELIEVE THAT THEY WERE HAVING TROUBLE STAFFING THE SHIFTS DURING THE DAY. IF WE WOULD HAVE HAD 3 CTLRS ON THIS NIGHT IT WOULD HAVE GIVEN US THE ABILITY TO SPLIT THE SECTOR AND HAVE A RADAR ASSOCIATE FLOAT BTWN THE 2 SECTORS ASSISTING EITHER RADAR CTLR. THIS WOULD HAVE PROVIDED A MORE STABLE AND WORKABLE SITUATION.

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.