Incident at GANDER INTL NL (CYQX) (Weather - clear air turbulence (CAT)/turbulence, Conflict - potential, ATM - other)
2003-01-22: TSB Update - 2003/01/21 - A03A0001: BAW219, a British Airways B747-400 was en route from London to Denver at FL360 crossing 61N/040W at 1911 UTC, estimating 60N/050W at 1946 UTC. ICE643, and Icelandair B757-200 was en route from Keflavik to Washington at FL350 crossing 61N/040W at 1907, estimating 59N/050W at 1945 UTC. At 1923 UTC, the flight crew of BAW219 requested a lower altitude due to turbulence; however, Gander was unable to issue a clearance due to traffic. The crew then informed Gander that they had ICE643 on TCAS at 40 nm ahead and that the aircraft (ICE643) was indicating climbing and descending as much as 200 feet. BAW219 then descended to FL310 without a clearance and, upon reaching that altitude, was issued a revised clearance to maintain FL310. The aircraft exited Canadian airspace without further incident.
2003-01-06: A British Airways B747 was enroute from Heathrow to Denver at Flight Level 360 estimating 60N 50W at 1945Z. An Icelandair B757 at Flight Level 350 enroute from Keflavik to Baltimore-Washington was by 61N 40W at 1907Z and estimating 59N 50W at 1945Z. The B747 requested a lower altitude due to reported turbulence, and was told this was unable due to traffic. The British Airways B747 advised he was watching the B757 on TCAS 40NM ahead and that the B757 was showing it was gaining and losing upwards to 200 ft. The British Airways B747 descended without clearance to Flight Level 310 and was then issued a new Oceanic clearance at that level.
|Occurred At||- 19:23|
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