Narrative:

Small transport X, an AC50 twin commander, 3 mi west of the sac VOR at 6000 ft was on a 090 degree vector for en route spacing to oak. Atx Y, a PA31, was at 6000 ft 3 mi north of the sac VOR sbound. I instructed Y to climb and maintain 7000 ft. The pilot advised that the last controller had assigned him 6000 ft. I then instructed X to climb immediately and maintain 7000 ft. The pilot of X did not acknowledge the instruction but I did observe the aircraft climbing out of 6000 ft. I then advised Y to maintain 6000 ft and called traffic at his '2 O'clock, 2 mi, a twin commander climbing out of 6000 ft.' I advised Y to maintain visual separation with the aircraft. The problem arose when I started getting busy flowing traffic to oakland. When smf tower called for release of 2 aircraft for oakland I was already aware of 2 overflts approaching my airspace also for oakland. Then sac tower called for release on an aircraft also to oakland. I also had 3 other aircraft on frequency at the time and was working the position by myself. When smf called again for 2 more departures to oakland I told them to hold for release. It was at this time I called for a coordinator. I believe that I called late for help. I was plenty busy flowing and talking to airplanes. Having to talk to smf and sac towers and to suu approach control distracted me long enough to allow these 2 aircraft to lose standard separation.

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Original NASA ASRS Text

Title: SMT X SAME ALT ASSIGNED HAD LTSS FROM ATX Y. SYS ERROR.

Narrative: SMT X, AN AC50 TWIN COMMANDER, 3 MI W OF THE SAC VOR AT 6000 FT WAS ON A 090 DEG VECTOR FOR ENRTE SPACING TO OAK. ATX Y, A PA31, WAS AT 6000 FT 3 MI N OF THE SAC VOR SBOUND. I INSTRUCTED Y TO CLB AND MAINTAIN 7000 FT. THE PLT ADVISED THAT THE LAST CTLR HAD ASSIGNED HIM 6000 FT. I THEN INSTRUCTED X TO CLB IMMEDIATELY AND MAINTAIN 7000 FT. THE PLT OF X DID NOT ACKNOWLEDGE THE INSTRUCTION BUT I DID OBSERVE THE ACFT CLBING OUT OF 6000 FT. I THEN ADVISED Y TO MAINTAIN 6000 FT AND CALLED TFC AT HIS '2 O'CLOCK, 2 MI, A TWIN COMMANDER CLBING OUT OF 6000 FT.' I ADVISED Y TO MAINTAIN VISUAL SEPARATION WITH THE ACFT. THE PROB AROSE WHEN I STARTED GETTING BUSY FLOWING TFC TO OAKLAND. WHEN SMF TWR CALLED FOR RELEASE OF 2 ACFT FOR OAKLAND I WAS ALREADY AWARE OF 2 OVERFLTS APCHING MY AIRSPACE ALSO FOR OAKLAND. THEN SAC TWR CALLED FOR RELEASE ON AN ACFT ALSO TO OAKLAND. I ALSO HAD 3 OTHER ACFT ON FREQ AT THE TIME AND WAS WORKING THE POS BY MYSELF. WHEN SMF CALLED AGAIN FOR 2 MORE DEPS TO OAKLAND I TOLD THEM TO HOLD FOR RELEASE. IT WAS AT THIS TIME I CALLED FOR A COORDINATOR. I BELIEVE THAT I CALLED LATE FOR HELP. I WAS PLENTY BUSY FLOWING AND TALKING TO AIRPLANES. HAVING TO TALK TO SMF AND SAC TWRS AND TO SUU APCH CTL DISTRACTED ME LONG ENOUGH TO ALLOW THESE 2 ACFT TO LOSE STANDARD SEPARATION.

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.