Four people including three crew were injured after an Air New Zealand flight hit turbulence, 40 minutes into a trip from Vietnam to Auckland.
Passengers on flight NZ268 from Ho Chi Minh City on Sunday described the experience as a "flight from hell".
One passenger said the aircraft dropped 100ft.
"It came on so fast. 20 seconds of bumps then a drop off then five seconds later up we went followed by a 100 foot fall," Vince Newbold said.
Another passenger, Emma Te Paa, said crew were thrown to the ceiling. She posted on Facebook that the plane was first delayed by two hours because of an issue with the brakes.
Then the "flight from hell" took off with everything going well until the plane struck turbulence an hour into the trip.
"As the air hostess hands me my tray we hit some really bad turbulence, the plane drops and all my food flies all over the floor and me," Ms Te Paa said.
"Everyone is screaming and we have no idea what is going on.
"A few minutes pass and the crew calling for a doctor over the loud speaker, two crew members had suffered critical injuries, the turbulence had thrown them up to the ceiling, another was injured."
Ms Te Paa said the plane had to return to Ho Chi Minh City to get them to the nearest hospital.
Mr Newbold said as the plane hit turbulence "things went flying".
"Two cabin crew are injured with head injuries and a doctor on board said we need to land ASAP," he wrote in an email.
A decision was made to return to Vietnam, as Darwin was deemed too far away for urgent treatment.
He described it as "spooky" and better than any roller coaster he had even been on.
A spokeswoman for Air New Zealand said the four on board suffered minor injuries.
The aircraft landed safely and without further incident in Vietnam about 8.20am on Sunday. (NZ time).
The injured were assessed and treated by medical staff.
The plane took off again this morning and was due to arrive in Auckland in the evening.
"We thank customers for their patience," the spokeswoman said.
