Narrative:

London control was very busy at the time of contact, gave us a heading off airways for traffic. After approximately 15 mins, both pilots noticed we were significantly south of course -- necessary to make our atlantic crossing entry point. Captain (PNF) queried center about heading. Told to remain on heading by center. Moments later, received TCASII RA and responded to climb. Traffic behind and under us climbing toward us. PNF declared to center that we were responding to TCASII. This was new controller who seemed confused as to who we were, then gave us turn to our atlantic entry point, told us traffic was military fighter coming to intercept and check us out and gave us frequency that we should be on. We had climbed to FL320 during our RA, trying to avoid the traffic warning. It seems that the first london controller either missed handing us off, or got our flight number confused with similar one of same carrier and we wandered into military airspace. When controllers changed, new one hadn't any idea where we were, thought we'd been switched. Possible factors: very busy first controller. Similar call signs. Controller change with possible information (about us) missing during the xfer. Aggressive fighter intercept causing RA and response. I'm certain that we didn't miss the frequency xfer if there was one since we were both very aware of being so far south of intended track and PNF queried 2 times about remaining on that assigned heading.

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Original NASA ASRS Text

Title: ACR ON VECTOR ENTERS MIL AIRSPACE RESULTING IN INTERCEPT AND TCASII RA. ARTCC LOST TRACK OF ACR ON HDOF BTWN CTLRS.

Narrative: LONDON CTL WAS VERY BUSY AT THE TIME OF CONTACT, GAVE US A HDG OFF AIRWAYS FOR TFC. AFTER APPROX 15 MINS, BOTH PLTS NOTICED WE WERE SIGNIFICANTLY S OF COURSE -- NECESSARY TO MAKE OUR ATLANTIC XING ENTRY POINT. CAPT (PNF) QUERIED CTR ABOUT HDG. TOLD TO REMAIN ON HDG BY CTR. MOMENTS LATER, RECEIVED TCASII RA AND RESPONDED TO CLB. TFC BEHIND AND UNDER US CLBING TOWARD US. PNF DECLARED TO CTR THAT WE WERE RESPONDING TO TCASII. THIS WAS NEW CTLR WHO SEEMED CONFUSED AS TO WHO WE WERE, THEN GAVE US TURN TO OUR ATLANTIC ENTRY POINT, TOLD US TFC WAS MIL FIGHTER COMING TO INTERCEPT AND CHK US OUT AND GAVE US FREQ THAT WE SHOULD BE ON. WE HAD CLBED TO FL320 DURING OUR RA, TRYING TO AVOID THE TFC WARNING. IT SEEMS THAT THE FIRST LONDON CTLR EITHER MISSED HANDING US OFF, OR GOT OUR FLT NUMBER CONFUSED WITH SIMILAR ONE OF SAME CARRIER AND WE WANDERED INTO MIL AIRSPACE. WHEN CTLRS CHANGED, NEW ONE HADN'T ANY IDEA WHERE WE WERE, THOUGHT WE'D BEEN SWITCHED. POSSIBLE FACTORS: VERY BUSY FIRST CTLR. SIMILAR CALL SIGNS. CTLR CHANGE WITH POSSIBLE INFO (ABOUT US) MISSING DURING THE XFER. AGGRESSIVE FIGHTER INTERCEPT CAUSING RA AND RESPONSE. I'M CERTAIN THAT WE DIDN'T MISS THE FREQ XFER IF THERE WAS ONE SINCE WE WERE BOTH VERY AWARE OF BEING SO FAR S OF INTENDED TRACK AND PNF QUERIED 2 TIMES ABOUT REMAINING ON THAT ASSIGNED HDG.

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.