Incident at Vicinity of 47N/50W (TCAS alert, Conflict - loss of separation)
2005-03-11: The US Airways Airbus 330 (USA98) was at FL350 and the British Airways Boeing 777 (BAW188) was at FL370 operating same direction (eastbound) on same route with longitudinal spacing of less than one (1) NM. USA98 cleared to climb to FL360 and was observed passing FL35.7 when BAW188 reported a TCAS RA and climbed to FL380. Approximately two (2) minutes later BAW188 was in descent to FL370 when USA98 received TCAS RA to descend. USA98 descended to FL350 and subsequently returned to FL360 crossing 47N50W. No other traffic. Light to moderate turbulence reported in area where TCAS were activated. Controller had earlier issued SIGMET A1 advisories to all aircraft.
2005-03-15: TSB Update A05A0033: USA98, an Airbus 330 (FL350) and BAW188, a Boeing 767-200 (FL370), were eastbound on the same routing with longitudinal spacing of less than one mile. USA98 was cleared to climb to FL360, and was observed to be passing FL35.7 when BAW188 reported a TCAS RA. BAW188 climbed to FL380. About two minutes later BAW188 was descending back to FL370 when USA98 received a TCAS RA to descend. USA98 descended to FL350, and subsequently returned to FL360 crossing 47N50W. There was no loss of separation, and no other traffic was affected. Light to moderate turbulence was reported in the area where the TCAS alerts occurred. The controller had earlier issued a related SIGMET advisory to all aircraft.
|Occurred At||- 04:10|
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