9S947 - Incident: Southern B772 at New York on Nov 15th 2020

A Southern Air Boeing 777-200 freighter, registration N702GT performing flight 9S-947 from New York JFK,NY (USA) to Seoul (South Korea), was climbing out of JFK's runway 22R climbing through about 5000 feet when the crew contacted departure advising they were climbing to 5000 feet. They were cleared to climb to 11000 feet, the aircraft continued climb, the pilot monitoring read back the clearance to climb to 11000 feet when he shouted, obviously to the pilot flying but with radio microphone open: "Stall! Stall! Stall! Stall! Stall!", then added "Standby" (obviously directed at ATC). The speed over ground had decayed from about 273 knots to 256 knots while climbing above 5000 feet, the aircraft began to descend from 5150 feet and stabilized about 200 feet lower. In the meantime the controller received several requests from other aircraft and just replied "Standby" to the other aircraft. The controller queried whether they were ready to climb now, the crew again replied "Standby". About 90 seconds after the stall calls the speed had recovered to 277 knots over ground and was accelerating, the crew indicated they were ready to climb again, everything was good again and were cleared to continue their climb. The controller also resumed normal service to all aircraft. The B772 continued their flight to Seoul where the aircraft landed safely about 14.5 hours later.