Narrative:

Air carrier X inbound to lax on sadde 5 arrival. Just prior to bayst intersection we were given direct to smo. We were level at 10000 ft, 250 KTS. Approximately 5 mi northwest of small transport, 2 targets appeared on TCASII as TA's at 1-2 O'clock position, 5-10 mi at 9300 ft. Targets then became 1 TA and were climbing. TCASII RA was issued to descend just as we started to inquire about traffic. (ATC never issued a TA.) began immediate descent per RA and advised ATC we were descending. He said to climb. First officer reiterated that we were descending per the RA. ATC responded adamantly and frantically to climb. We had descended approximately 500 ft and were IMC. We then followed ATC's command to climb. TCASII advised clear of conflict shortly thereafter. An FAA observer was in the jumpseat and stated he saw a 'contrail' pass by the right side window. Talked to socal supervisor. He stated the aircraft in conflict was air carrier Y on a vtu 2 departure and was cleared to climb to 13000 ft. (He stated the aircraft should have been on the gorman departure.) the controller turned the aircraft to a 310 degree heading, clearance to 13000 ft. Usually, aircraft on the gorman departure are stopped at 9000 ft because arrival traffic crosses at 10000 ft. ATC was unaware of conflict until evasive action was taken. Supervisor stated that conflicting aircraft did not 'bust' an altitude (since he was cleared to 13000 ft). He told me air carrier Y was responding to a climb RA and had reached 10500 ft. ATC (on another frequency from ours) issued commands for them to descend. Since we were IMC, I don't know at this point how close we came. ATC was definitely not in the loop until after the conflict occurred. This occurrence appears to be a result of ATC confusion over the departure/altitude assigned to the other aircraft, and a lack of controller awareness. An interesting situation. Both aircraft were responding appropriately to TCASII RA's. Both later were given opposite commands by ATC on 2 separate frequencys, IMC. Callback conversation with reporter revealed the following information: reporter said the 2 targets were about an inch apart on the TCASII display and merged together at 9800 ft. Reporter stated she was following the RA and descending when the controller started screaming to disregard the RA and climb, climb now. Reporter felt between a rock and a hard place with 2 conflicting commands -- TCASII ordering descend and controller screaming climb. Reporter said during flight crew ATC review she was informed it was air carrier Y and the miss distance was 1.44 mi and 200 ft.

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Original NASA ASRS Text

Title: ACR X TCASII TA RA WITH ACR Y CLB THROUGH OCCUPIED ALT HAD LTSS FROM Y. EVASIVE ACTION TAKEN. SYS ERROR.

Narrative: ACR X INBOUND TO LAX ON SADDE 5 ARR. JUST PRIOR TO BAYST INTXN WE WERE GIVEN DIRECT TO SMO. WE WERE LEVEL AT 10000 FT, 250 KTS. APPROX 5 MI NW OF SMT, 2 TARGETS APPEARED ON TCASII AS TA'S AT 1-2 O'CLOCK POS, 5-10 MI AT 9300 FT. TARGETS THEN BECAME 1 TA AND WERE CLBING. TCASII RA WAS ISSUED TO DSND JUST AS WE STARTED TO INQUIRE ABOUT TFC. (ATC NEVER ISSUED A TA.) BEGAN IMMEDIATE DSCNT PER RA AND ADVISED ATC WE WERE DSNDING. HE SAID TO CLB. FO REITERATED THAT WE WERE DSNDING PER THE RA. ATC RESPONDED ADAMANTLY AND FRANTICALLY TO CLB. WE HAD DSNDED APPROX 500 FT AND WERE IMC. WE THEN FOLLOWED ATC'S COMMAND TO CLB. TCASII ADVISED CLR OF CONFLICT SHORTLY THEREAFTER. AN FAA OBSERVER WAS IN THE JUMPSEAT AND STATED HE SAW A 'CONTRAIL' PASS BY THE R SIDE WINDOW. TALKED TO SOCAL SUPVR. HE STATED THE ACFT IN CONFLICT WAS ACR Y ON A VTU 2 DEP AND WAS CLRED TO CLB TO 13000 FT. (HE STATED THE ACFT SHOULD HAVE BEEN ON THE GORMAN DEP.) THE CTLR TURNED THE ACFT TO A 310 DEG HDG, CLRNC TO 13000 FT. USUALLY, ACFT ON THE GORMAN DEP ARE STOPPED AT 9000 FT BECAUSE ARR TFC CROSSES AT 10000 FT. ATC WAS UNAWARE OF CONFLICT UNTIL EVASIVE ACTION WAS TAKEN. SUPVR STATED THAT CONFLICTING ACFT DID NOT 'BUST' AN ALT (SINCE HE WAS CLRED TO 13000 FT). HE TOLD ME ACR Y WAS RESPONDING TO A CLB RA AND HAD REACHED 10500 FT. ATC (ON ANOTHER FREQ FROM OURS) ISSUED COMMANDS FOR THEM TO DSND. SINCE WE WERE IMC, I DON'T KNOW AT THIS POINT HOW CLOSE WE CAME. ATC WAS DEFINITELY NOT IN THE LOOP UNTIL AFTER THE CONFLICT OCCURRED. THIS OCCURRENCE APPEARS TO BE A RESULT OF ATC CONFUSION OVER THE DEP/ALT ASSIGNED TO THE OTHER ACFT, AND A LACK OF CTLR AWARENESS. AN INTERESTING SIT. BOTH ACFT WERE RESPONDING APPROPRIATELY TO TCASII RA'S. BOTH LATER WERE GIVEN OPPOSITE COMMANDS BY ATC ON 2 SEPARATE FREQS, IMC. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR SAID THE 2 TARGETS WERE ABOUT AN INCH APART ON THE TCASII DISPLAY AND MERGED TOGETHER AT 9800 FT. RPTR STATED SHE WAS FOLLOWING THE RA AND DSNDING WHEN THE CTLR STARTED SCREAMING TO DISREGARD THE RA AND CLB, CLB NOW. RPTR FELT BTWN A ROCK AND A HARD PLACE WITH 2 CONFLICTING COMMANDS -- TCASII ORDERING DSND AND CTLR SCREAMING CLB. RPTR SAID DURING FLC ATC REVIEW SHE WAS INFORMED IT WAS ACR Y AND THE MISS DISTANCE WAS 1.44 MI AND 200 FT.

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.