The aviation tracking site FlightRadar24 says, based on its data, that the turbulence on Singapore Airlines flight SQ321 occurred over Myanmar at approximately 7:49 a.m. UTC (3:49 a.m. ET). This lines up with a statement from the airline stating that the plane, “encountered sudden extreme turbulence over the Irrawaddy Basin [a river in Myanmar] at 37,000 feet, about 10 hours after departure.”FlightRadar24 said in a blog post that, according to its data, at that time, ”the flight encountered a rapid change in vertical rate, consistent with a sudden turbulence event.”The data…