Narrative:

While on radar vector to ILS runway 24R at lax, on a heading of 070 degrees, socal approach issued us a clearance. At the same time there was some interference from another transmission, but the first officer and I both thought we heard 'air carrier flight X, turn to 160 degrees,' which the first officer read back as I turned to that heading. After the turn, we saw 2 aircraft on final to lax -- 1 at our 10-11 O'clock, and another at our 1-2 O'clock position. We were not yet able to decide if they were on approach to our runway, 24R, or were on final for runway 25L. As it became apparent that this spacing was not going to be adequate, the controller called, asked us why we were on this heading, that we should be on a heading of 060 degrees. He then gave us vectors northwest and out of the conflict with the other aircraft that were on approach to runway 24R. Corrective actions: probably a good idea to include the word, 'right or left' when acknowledging a turn, that might, in some cases, alert the controller that an incorrect turn is about to be made. Anytime a transmission is 'covered,' partially blocked, garbled or has any potential for misunderstanding, I believe we should state 'transmission blocked, understand you said...' or 'verify turn to...' as a clue to other person to doublechk my readback, I might have misunderstood what you said. Supplemental information from acn 341648: issued heading 060 degrees to air carrier X and transmission was blocked. Issued heading again to air carrier X but air carrier X did not use a call sign, just said '160' and I heard the '60' portion. Made several other xmissions and while scanning the sector saw air carrier X in a southerly heading. Took immediate action to avoid midair. If air carrier X had used their call sign and read back the heading I would have heard them. Other considerations were pilots not listening that I was saying something before they cut in and the quality of the radios at socal TRACON have always been worse than when we were in los angeles. Too many switches and relays to go through.

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Original NASA ASRS Text

Title: ACR FLT EXPERIENCES HDG TRACK DEV DURING A CLRNC INTERP PROB WITH A CLRNC READBACK IMPROPERLY PERFORMED. ALERT APCH CTLR SEES IMPENDING CONFLICT AND ISSUES A NEW CLRNC FOR ACR. CTLR CITES ANTIQUATED RADIO COM EQUIP AT SOCAL APCH AS BEING DIFFICULT TO USE.

Narrative: WHILE ON RADAR VECTOR TO ILS RWY 24R AT LAX, ON A HDG OF 070 DEGS, SOCAL APCH ISSUED US A CLRNC. AT THE SAME TIME THERE WAS SOME INTERFERENCE FROM ANOTHER XMISSION, BUT THE FO AND I BOTH THOUGHT WE HEARD 'ACR FLT X, TURN TO 160 DEGS,' WHICH THE FO READ BACK AS I TURNED TO THAT HDG. AFTER THE TURN, WE SAW 2 ACFT ON FINAL TO LAX -- 1 AT OUR 10-11 O'CLOCK, AND ANOTHER AT OUR 1-2 O'CLOCK POS. WE WERE NOT YET ABLE TO DECIDE IF THEY WERE ON APCH TO OUR RWY, 24R, OR WERE ON FINAL FOR RWY 25L. AS IT BECAME APPARENT THAT THIS SPACING WAS NOT GOING TO BE ADEQUATE, THE CTLR CALLED, ASKED US WHY WE WERE ON THIS HDG, THAT WE SHOULD BE ON A HDG OF 060 DEGS. HE THEN GAVE US VECTORS NW AND OUT OF THE CONFLICT WITH THE OTHER ACFT THAT WERE ON APCH TO RWY 24R. CORRECTIVE ACTIONS: PROBABLY A GOOD IDEA TO INCLUDE THE WORD, 'RIGHT OR LEFT' WHEN ACKNOWLEDGING A TURN, THAT MIGHT, IN SOME CASES, ALERT THE CTLR THAT AN INCORRECT TURN IS ABOUT TO BE MADE. ANYTIME A XMISSION IS 'COVERED,' PARTIALLY BLOCKED, GARBLED OR HAS ANY POTENTIAL FOR MISUNDERSTANDING, I BELIEVE WE SHOULD STATE 'XMISSION BLOCKED, UNDERSTAND YOU SAID...' OR 'VERIFY TURN TO...' AS A CLUE TO OTHER PERSON TO DOUBLECHK MY READBACK, I MIGHT HAVE MISUNDERSTOOD WHAT YOU SAID. SUPPLEMENTAL INFO FROM ACN 341648: ISSUED HDG 060 DEGS TO ACR X AND XMISSION WAS BLOCKED. ISSUED HDG AGAIN TO ACR X BUT ACR X DID NOT USE A CALL SIGN, JUST SAID '160' AND I HEARD THE '60' PORTION. MADE SEVERAL OTHER XMISSIONS AND WHILE SCANNING THE SECTOR SAW ACR X IN A SOUTHERLY HDG. TOOK IMMEDIATE ACTION TO AVOID MIDAIR. IF ACR X HAD USED THEIR CALL SIGN AND READ BACK THE HDG I WOULD HAVE HEARD THEM. OTHER CONSIDERATIONS WERE PLTS NOT LISTENING THAT I WAS SAYING SOMETHING BEFORE THEY CUT IN AND THE QUALITY OF THE RADIOS AT SOCAL TRACON HAVE ALWAYS BEEN WORSE THAN WHEN WE WERE IN LOS ANGELES. TOO MANY SWITCHES AND RELAYS TO GO THROUGH.

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.