Narrative:

We departed lax from runway 24L on a 250 degree heading and lax tower handed us off to socal departure. Socal departure instructed us to climb and maintain 13000 ft. The captain (PNF), responded 'climb and maintain 13000 ft, air carrier X.' socal then replied 'and turn left heading 160 degrees,' right after the captain replied to the altitude assignment. The captain read back the heading,' turn left heading 160 degrees, air carrier X.' I initiated a turn to the left and as I was rolling out on a heading of 160 degrees, socal asked us where we were going and issued an immediate turn back to 250 degrees. Socal also amended our climb clearance and instructed us to leveloff at 4000 ft MSL, but we were already at 4500 ft and climbing. Socal then asked us to leveloff at 5000 ft, which we complied with. As we were turning to a heading of 160 degrees, the captain pointed out traffic at about our 10 O'clock position, and we were maintaining visual separation from that aircraft, even though socal did not point out that traffic to us. Apparently, the turn to 160 degrees was issued to us in error or possibly it was not intended for us. The non standard instructions 'and turn left heading 160 degrees,' contributed to the confusion. The instructions should have been preceeded with our call sign (eg: air carrier X turn left heading 160 degrees.) the socal controller was issuing instructions in a 'rapid fire' manner that was not necessary. When instructions are issued in a rush, there are often errors in the interpretation of the instructions by the flight crew. When this happens, ATC has to repeat the instructions and the flight crew has to read back the instructions which leads to more radio congestion and possibly a compromise in safety. Socal asked the captain to call them by phone when we got to our destination. The captain called socal and the person who answered the call told him that socal approach was going to conduct an internal review of the situation. On this flight our jump seat was occupied by a company check airman who was conducting a line check. He was wearing a headset and was listening to the communications between the flight crew and ATC. His interpretation of the above events are identical.

Related reports:

Google
 

Original NASA ASRS Text

Title: LAX DEP CTLR DID NOT REALIZE THAT THE WRONG ACFT FLC RESPONDED TO HIS HEADING CHANGE INSTRUCTIONS DURING THE CLBOUT AFTER TKOF OF 2 ACR ACFT CAUSING LTSS.

Narrative: WE DEPARTED LAX FROM RWY 24L ON A 250 DEG HDG AND LAX TWR HANDED US OFF TO SOCAL DEP. SOCAL DEP INSTRUCTED US TO CLB AND MAINTAIN 13000 FT. THE CAPT (PNF), RESPONDED 'CLB AND MAINTAIN 13000 FT, ACR X.' SOCAL THEN REPLIED 'AND TURN L HEADING 160 DEGS,' RIGHT AFTER THE CAPT REPLIED TO THE ALT ASSIGNMENT. THE CAPT READ BACK THE HEADING,' TURN L HEADING 160 DEGS, ACR X.' I INITIATED A TURN TO THE L AND AS I WAS ROLLING OUT ON A HEADING OF 160 DEGS, SOCAL ASKED US WHERE WE WERE GOING AND ISSUED AN IMMEDIATE TURN BACK TO 250 DEGS. SOCAL ALSO AMENDED OUR CLB CLRNC AND INSTRUCTED US TO LEVELOFF AT 4000 FT MSL, BUT WE WERE ALREADY AT 4500 FT AND CLBING. SOCAL THEN ASKED US TO LEVELOFF AT 5000 FT, WHICH WE COMPLIED WITH. AS WE WERE TURNING TO A HEADING OF 160 DEGS, THE CAPT POINTED OUT TFC AT ABOUT OUR 10 O'CLOCK POS, AND WE WERE MAINTAINING VISUAL SEPARATION FROM THAT ACFT, EVEN THOUGH SOCAL DID NOT POINT OUT THAT TFC TO US. APPARENTLY, THE TURN TO 160 DEGS WAS ISSUED TO US IN ERROR OR POSSIBLY IT WAS NOT INTENDED FOR US. THE NON STANDARD INSTRUCTIONS 'AND TURN L HEADING 160 DEGS,' CONTRIBUTED TO THE CONFUSION. THE INSTRUCTIONS SHOULD HAVE BEEN PRECEEDED WITH OUR CALL SIGN (EG: ACR X TURN L HEADING 160 DEGS.) THE SOCAL CTLR WAS ISSUING INSTRUCTIONS IN A 'RAPID FIRE' MANNER THAT WAS NOT NECESSARY. WHEN INSTRUCTIONS ARE ISSUED IN A RUSH, THERE ARE OFTEN ERRORS IN THE INTERP OF THE INSTRUCTIONS BY THE FLC. WHEN THIS HAPPENS, ATC HAS TO REPEAT THE INSTRUCTIONS AND THE FLC HAS TO READ BACK THE INSTRUCTIONS WHICH LEADS TO MORE RADIO CONGESTION AND POSSIBLY A COMPROMISE IN SAFETY. SOCAL ASKED THE CAPT TO CALL THEM BY PHONE WHEN WE GOT TO OUR DEST. THE CAPT CALLED SOCAL AND THE PERSON WHO ANSWERED THE CALL TOLD HIM THAT SOCAL APCH WAS GOING TO CONDUCT AN INTERNAL REVIEW OF THE SIT. ON THIS FLT OUR JUMP SEAT WAS OCCUPIED BY A COMPANY CHK AIRMAN WHO WAS CONDUCTING A LINE CHK. HE WAS WEARING A HEADSET AND WAS LISTENING TO THE COMS BTWN THE FLC AND ATC. HIS INTERP OF THE ABOVE EVENTS ARE IDENTICAL.

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.