I was tracking the above aircraft (Virgin Atlantic 30 August 2013 Boston to Heathrow) last night as my daughter was returning home from Boston and noticed at 3.16 am the speed dropped significantly for one minute and then returned to normal!
03:15 52.7667 -50.9000 67° East 540 621 39,000
03:16 52.8500 -50.4833 72° East 290 334 39,000
03:17 52.9000 -50.2500 70° East 510 587 39,000
Does anyone know why this would happen? The altitude remained the same.
Thanks in advance