Narrative:

[We were] given takeoff clearance approximately 30/35 seconds after a heavy B747. [We] delayed takeoff for approximately 30 more seconds. Wind report was 280/7. Rough ride after takeoff 300 ft to 1;300 ft. [We] reported event to egll tower. I thought egll provided a 1 minute minimum delay interval between heavy aircraft. They didn't. [They] should consider longer delays when winds are calm or straight down the runway.

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Original NASA ASRS Text

Title: B777-200 pilot reported encountering wake turbulence after takeoff from EGLL in trail of a B747. Pilot commented he felt separation standards were not followed by ATC.

Narrative: [We were] given takeoff clearance approximately 30/35 seconds after a heavy B747. [We] delayed takeoff for approximately 30 more seconds. Wind report was 280/7. Rough ride after takeoff 300 FT to 1;300 FT. [We] reported event to EGLL Tower. I thought EGLL provided a 1 minute minimum delay interval between heavy aircraft. They didn't. [They] should consider longer delays when winds are calm or straight down the runway.

Data retrieved from NASA's ASRS site 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.