Narrative:

This report pertains to 2 operrors and a deviation within about 15 mins of each other. Traffic was bordering on heavy. I was talking to a total of 10 aircraft, coordinating 4 altitude changes, tower was coordination departures and I was having trouble getting 1 VFR to answer me. 2 radar position open. No radar associates. Controller sitting next to me had 1 aircraft he was controling. Supervisor was watching, facility manager started watching at some point. The basic problem was controller overload and no one realized it so help was not given. Generally, a radar associate position would have been open to help me based on the number of strips in my proposal bay. Small aircraft X was inbound 40 wnw of oma. He was at 7000 ft and told to descend and maintain 4000 ft. Aircraft Y departure oma wbound climb 6000 ft. Aircraft Y requested 4000 ft. I approved it. Then realized small aircraft X was descending to 4000 ft. 4000 ft was not appropriate for aircraft Y. Aircraft Y climbed to 5000 ft to go over small aircraft X. Small aircraft X only descended 2000 ft (down to 5000 ft) in 10 mins. Collision alert was activated and both aircraft turned to keep from hitting. After this I was relieved but forgot to tell the controller relieving me to either climb aircraft Y back to 4000 ft or coordination 5000 ft with ZMP. Operational error #2: small aircraft C departure oma direct apa climb 8000 ft. Small transport D direct oma to gri, climb to 6000 ft. Small aircraft C turned on course (RNAV equipped). Small transport D vectored around small aircraft C when it appeared that small aircraft C was on a steady course, small transport D turned to heading 250 which indicated he still would be flying away from small aircraft C. Data plot later showed small aircraft C turned more westerly. Small transport D climbed faster separation was lost. I did not see this coming and had I not been so busy, probably would have seen the problem develop.

Related reports:

Google
 

Original NASA ASRS Text

Title: SMA X HAD LTSS FROM ACFT Y. SYS ERROR. SMA C HAD LTSS FROM SMT D. SYS ERROR.

Narrative: THIS RPT PERTAINS TO 2 OPERRORS AND A DEV WITHIN ABOUT 15 MINS OF EACH OTHER. TFC WAS BORDERING ON HVY. I WAS TALKING TO A TOTAL OF 10 ACFT, COORDINATING 4 ALT CHANGES, TWR WAS COORD DEPS AND I WAS HAVING TROUBLE GETTING 1 VFR TO ANSWER ME. 2 RADAR POS OPEN. NO RADAR ASSOCIATES. CTLR SITTING NEXT TO ME HAD 1 ACFT HE WAS CTLING. SUPVR WAS WATCHING, FACILITY MGR STARTED WATCHING AT SOME POINT. THE BASIC PROBLEM WAS CTLR OVERLOAD AND NO ONE REALIZED IT SO HELP WAS NOT GIVEN. GENERALLY, A RADAR ASSOCIATE POS WOULD HAVE BEEN OPEN TO HELP ME BASED ON THE NUMBER OF STRIPS IN MY PROPOSAL BAY. SMA X WAS INBOUND 40 WNW OF OMA. HE WAS AT 7000 FT AND TOLD TO DSND AND MAINTAIN 4000 FT. ACFT Y DEP OMA WBOUND CLB 6000 FT. ACFT Y REQUESTED 4000 FT. I APPROVED IT. THEN REALIZED SMA X WAS DSNDING TO 4000 FT. 4000 FT WAS NOT APPROPRIATE FOR ACFT Y. ACFT Y CLBED TO 5000 FT TO GO OVER SMA X. SMA X ONLY DSNDED 2000 FT (DOWN TO 5000 FT) IN 10 MINS. COLLISION ALERT WAS ACTIVATED AND BOTH ACFT TURNED TO KEEP FROM HITTING. AFTER THIS I WAS RELIEVED BUT FORGOT TO TELL THE CTLR RELIEVING ME TO EITHER CLB ACFT Y BACK TO 4000 FT OR COORD 5000 FT WITH ZMP. OPERROR #2: SMA C DEP OMA DIRECT APA CLB 8000 FT. SMT D DIRECT OMA TO GRI, CLB TO 6000 FT. SMA C TURNED ON COURSE (RNAV EQUIPPED). SMT D VECTORED AROUND SMA C WHEN IT APPEARED THAT SMA C WAS ON A STEADY COURSE, SMT D TURNED TO HDG 250 WHICH INDICATED HE STILL WOULD BE FLYING AWAY FROM SMA C. DATA PLOT LATER SHOWED SMA C TURNED MORE WESTERLY. SMT D CLBED FASTER SEPARATION WAS LOST. I DID NOT SEE THIS COMING AND HAD I NOT BEEN SO BUSY, PROBABLY WOULD HAVE SEEN THE PROBLEM DEVELOP.

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.