Narrative:

On a lamborne departure from lgw, flight was climbing on an assigned heading to an assigned altitude of FL130 (altimeter 1013 MB). Female controller told flight to turn left to a heading of 020 degrees for traffic. Shortly thereafter when climbing through FL123, a male controller told us to level off at FL125 for traffic and then said turn left to a heading of (340 degrees?). This was immediately followed by instructions to descend to FL120. We complied without delay to all headings and altitudes assigned by london ATC. Apparently, the traffic conflict was a foreign air carrier. London was giving most of their attention to him, and indicated he was supposed to be at FL160. Foreign air carrier indicated he thought he was cleared to FL120. London told him they would be pulling the tapes. During vectoring turns, the first officer and jump seat pilot had in sight and stayed clear while complying with london ATC instructions. First officer air carrier passed above and slightly behind our flight. Subsequent to the above events, the male controller apologized to us for 'frightening' us as a result of the above mentioned exercise. These facts should be verified once the london ATC tapes are reviewed. The first officer was flying the departure until our flight was instructed to level off at FL125, at which time the captain took the aircraft and instructed the first officer to keep foreign air carrier in sight.

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Original NASA ASRS Text

Title: A B767-300 DEP EGKK (GATWICK) IS GIVEN AMENDED CLRNCS FOR ALT AND HEADING WHEN A FOREIGN BASED CARRIER OVERSHOOTS ITS ASSIGNED ALT AND IS IN CONFLICT WITH THE DEP PATH OF ACR X. EGTT, FO.

Narrative: ON A LAMBORNE DEP FROM LGW, FLT WAS CLBING ON AN ASSIGNED HEADING TO AN ASSIGNED ALT OF FL130 (ALTIMETER 1013 MB). FEMALE CTLR TOLD FLT TO TURN L TO A HEADING OF 020 DEGS FOR TFC. SHORTLY THEREAFTER WHEN CLBING THROUGH FL123, A MALE CTLR TOLD US TO LEVEL OFF AT FL125 FOR TFC AND THEN SAID TURN L TO A HEADING OF (340 DEGS?). THIS WAS IMMEDIATELY FOLLOWED BY INSTRUCTIONS TO DSND TO FL120. WE COMPLIED WITHOUT DELAY TO ALL HEADINGS AND ALTS ASSIGNED BY LONDON ATC. APPARENTLY, THE TFC CONFLICT WAS A FOREIGN ACR. LONDON WAS GIVING MOST OF THEIR ATTN TO HIM, AND INDICATED HE WAS SUPPOSED TO BE AT FL160. FOREIGN ACR INDICATED HE THOUGHT HE WAS CLRED TO FL120. LONDON TOLD HIM THEY WOULD BE PULLING THE TAPES. DURING VECTORING TURNS, THE FO AND JUMP SEAT PLT HAD IN SIGHT AND STAYED CLR WHILE COMPLYING WITH LONDON ATC INSTRUCTIONS. FO ACR PASSED ABOVE AND SLIGHTLY BEHIND OUR FLT. SUBSEQUENT TO THE ABOVE EVENTS, THE MALE CTLR APOLOGIZED TO US FOR 'FRIGHTENING' US AS A RESULT OF THE ABOVE MENTIONED EXERCISE. THESE FACTS SHOULD BE VERIFIED ONCE THE LONDON ATC TAPES ARE REVIEWED. THE FO WAS FLYING THE DEP UNTIL OUR FLT WAS INSTRUCTED TO LEVEL OFF AT FL125, AT WHICH TIME THE CAPT TOOK THE ACFT AND INSTRUCTED THE FO TO KEEP FOREIGN ACR IN SIGHT.

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.