“Rapid change” in g-force and altitude drop caused injuries in Singapore Airlines' flight SQ321

“Rapid change in gravitational force” combined with a 54 metre altitude drop resulted in injuries suffered onboard flight SQ321, an investigation by the Singaporean Ministry of Transport (MOT) and its Transport Safety Investigation Bureau (TSIB) revealed. The MOT said: ""This likely resulted in the occupants who were not belted up to become airborne. The vertical acceleration changed from negative 1.5G to positive 1.5G within 4 seconds. This likely resulted in the occupants who were airborne to fall back down. ""The rapid changes in [g-force] over the 4.6 seconds duration resulted in an altitude drop of 178ft, from 37,362ft to 37,184ft. This sequence of events likely caused the injuries to the crew and passengers."" One passenger died from a suspected heart attack, while several other passengers and crew were injured on the flight, operating on a 777-300ER, after it was hit by severe turbulence. Flight SQ321 had been flying from London Heathrow to Singapore, carrying 211 passengers and 18 crew onboard. The report also said a pilot was heard calling out during the flight that the fasten seatbelt sign had been switched on. “SIA is fully cooperating with the relevant authorities in the ongoing investigations into this incident,"" the airline said in a statement. ""The safety and well-being of our passengers and staff are our top priorities. ""We are committed to supporting our passengers and crew members who were on board SQ321 on that day, as well as their families and loved ones. This includes covering their medical and hospital expenses, as well as any additional assistance they may need. ""We deeply appreciate the invaluable assistance provided by the governments of Singapore and Thailand, as well as our many partners and the medical teams in both countries and around the world. We are also humbled by and grateful for the encouragement from our passengers and members of the public."" The investigation into flight SQ321 is still underway.