'Sheer terror': Passengers describe turbulence-hit plane that plummeted and put 20 in intensive care

Passengers on the Singapore Airlines flight that plummeted after hitting severe turbulence have described the “sheer terror” of the aircraft shuddering, loose items flying and people wrenched so badly that 20 remain in intensive care. One passanger says that “I arrived back in the airport and I couldn’t stop vomiting. I couldn’t walk, it was pretty bad." It's still not clear what caused the turbulence that sent the Boeing 777 carrying 211 passengers and 18 crew members on a 6,000-foot descent in about three minutes. Aviation investigators have arrived in Thailand and U.S. technical advisers will join them.