Sydney Morning Herald extract
Passenger Nicole Kearns, 33, who was flying with her one-year-old son, said she thought she detected the pilots throttling off to slow the engines while the plane was still climbing.
The captain then made his address just minutes into the flight, as the coastline was still in view.
"We were on ascent then the announcement came over that we'd have to turn around," she said. "
Ms Kearns, an experienced parachutist of 300 jumps, said that she felt no impact, or any unusual noise from the plane during take-off.
"I didn't hear anything or feel anything unusual," she said.
The plane turned and landed about 15 minutes later without incident, and was tailed by a ground vehicle with flashing lights as it taxied back to the terminal.
Passengers were kept on board for about 10 minutes while the plane was inspected on the ground, Ms Kearns said.
She said she believed the crew were still strapped in their seats when the incident occurred and were "extra courteous" to passengers when they were disembarked for replacement flights.