Narrative:

Air carrier X MD8O departed oak runway 29 on coast SID, climbing to 10000 with restr of 'X 4 DME west of oak at 2000,' and a govly C182, VFR, delaying within class B airspace at 3500 ft, approximately 10 northwest of sfo. The C182 was within the MD80's departure path -- but was far enough to the west of oak (approximately 7- 8 mi) to allow for a normal climb for a civil jet -- departing oak to climb above. I radar identified the MD80 and canceled the 2000 restr. I re-evaluated the situation when the MD80 and the C182 were approximately 5 NM apart -- and the MD80 was climbing through 3300 ft. Based upon this performance, I believed there would not be a problem obtaining 500 ft vertical separation. For the next 2-3 mi, however, the MD80 leveled at 3600 ft (the C182 was at 3500). The MD80 appeared to have stopped climbing -- so I then told X to 'expedite through 4000 ft,' and issued traffic on the C182. The crew of the MD80 then advised me that they were responding to an 'RA,' but still appeared level at 3600 to 3700. The crew reported the C182 'in sight,' but with less than required separation. After the aircraft replied, I asked the crew why they had leveled off, as I was counting on a normal climb rate to achieve separation and they responded that the TCASII had instructed them to descend. I do not think the crew actually descended -- based upon mode C information. I have no idea why they leveled at an altitude matching the altitude of the target. Perhaps if I had issued traffic information sooner, to let the crew know of my intentions, this situation could have been avoided.

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Original NASA ASRS Text

Title: ACR X NON ADHERENCE TO ATC CLRNC TCASII RA HAD LTSS FROM VFR SMA.

Narrative: ACR X MD8O DEPARTED OAK RWY 29 ON COAST SID, CLBING TO 10000 WITH RESTR OF 'X 4 DME W OF OAK AT 2000,' AND A GOVLY C182, VFR, DELAYING WITHIN CLASS B AIRSPACE AT 3500 FT, APPROX 10 NW OF SFO. THE C182 WAS WITHIN THE MD80'S DEP PATH -- BUT WAS FAR ENOUGH TO THE W OF OAK (APPROX 7- 8 MI) TO ALLOW FOR A NORMAL CLB FOR A CIVIL JET -- DEPARTING OAK TO CLB ABOVE. I RADAR IDENTIFIED THE MD80 AND CANCELED THE 2000 RESTR. I RE-EVALUATED THE SIT WHEN THE MD80 AND THE C182 WERE APPROX 5 NM APART -- AND THE MD80 WAS CLBING THROUGH 3300 FT. BASED UPON THIS PERFORMANCE, I BELIEVED THERE WOULD NOT BE A PROB OBTAINING 500 FT VERT SEPARATION. FOR THE NEXT 2-3 MI, HOWEVER, THE MD80 LEVELED AT 3600 FT (THE C182 WAS AT 3500). THE MD80 APPEARED TO HAVE STOPPED CLBING -- SO I THEN TOLD X TO 'EXPEDITE THROUGH 4000 FT,' AND ISSUED TFC ON THE C182. THE CREW OF THE MD80 THEN ADVISED ME THAT THEY WERE RESPONDING TO AN 'RA,' BUT STILL APPEARED LEVEL AT 3600 TO 3700. THE CREW RPTED THE C182 'IN SIGHT,' BUT WITH LESS THAN REQUIRED SEPARATION. AFTER THE ACFT REPLIED, I ASKED THE CREW WHY THEY HAD LEVELED OFF, AS I WAS COUNTING ON A NORMAL CLB RATE TO ACHIEVE SEPARATION AND THEY RESPONDED THAT THE TCASII HAD INSTRUCTED THEM TO DSND. I DO NOT THINK THE CREW ACTUALLY DSNDED -- BASED UPON MODE C INFO. I HAVE NO IDEA WHY THEY LEVELED AT AN ALT MATCHING THE ALT OF THE TARGET. PERHAPS IF I HAD ISSUED TFC INFO SOONER, TO LET THE CREW KNOW OF MY INTENTIONS, THIS SIT COULD HAVE BEEN AVOIDED.

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.