SQ321 severe turbulence: What is G-force?

Early findings into the extreme turbulence on Singapore Airlines flight SQ321 have been released. It showed that quick and sudden uncommanded altitude changes likely caused injuries. There were also rapid changes to gravitational or G-forces. Nadirah Zaidi explains what is a G-force, and what passengers might have felt during the turbulence. Independent aviation analyst Alvin Lie also shares more about the interim findings and what’s next for investigators.