When turbulence strikes, it's better when it happens before mealtime.

Instagram photos by a passenger on a recent Singapore Airlines flight SQ308 from Singapore to London show a chaotic mess after his flight hit a rough patch and lost altitude, sending meals flying. The passenger's coffee, he said, ended up on the ceiling.

The passengers were warned to expect a bit of turbulence, Alan Cross told ABC News. It was announced the breakfast service would be temporarily suspended and the fasten seat belt sign came on.

About a minute later, the captain came on with a rather urgent-sounding order for all flight attendants to immediately take their seats, Cross said.

"I remember thinking that that his tone was a bit odd," he said.

Cross described the turbulence that quickly followed as "like being in an elevator with a cut cable or free-falling from some amusement park ride."

Everything that wasn't tied down, including a few people, hit the ceiling, he said.

Cross said the flight attendants quickly came through the cabin to check for injuries and then began cleaning up the mess. The flight continued as normal for the next 10 hours, but the flight was met at Heathrow by paramedics. The passengers were given boxes of chocolates as they deplaned.

Singapore Airlines did not respond to ABC News' request for comment.

But the airline did tell Australia News, "Eleven passengers and one crew member sustained minor injuries when the aircraft experienced a sudden loss of altitude and were attended to by medical personnel on arrival at Heathrow Airport. Seat-belt signs were on at the time and meal services had already been suspended."

Cross said, "The cabin crew was amazing in the aftermath, as were fellow passengers who helped everyone around them then in a calm and efficient clean-up."

"And the chocolates were a nice touch from the airline. That's why Singapore will remain my favorite carrier in the world."

Cross didn't sustain any injuries in-flight. He only ended up with a bit of his neighbor's sausage down the back of his shirt.