The operator of Sydney's ferries has denied a new vessel was in the path of a cruise ship in Sydney Harbour when it suffered a steering failure.
Three catamaran ferries have been withdrawn from service following the incident that occurred when the Fairlight vessel was travelling from Manly to Circular Quay just before 5pm on Monday.
Transdev managing director Loretta Lynch told ABC Radio Sydney there was no risk to passengers.
"The master immediately slowed the ferry and switched to backup steering, which really only takes a few seconds, regained full control of the vessel, and made sure what the issue was," she said.
"He assessed that it was best to return the vessel to the wharf. He dropped off the passengers."
Ms Lynch disputed media reports that the Fairlight had been in the intended path of a cruise ship leaving Sydney Harbour.
"At all times, that ferry was well out of the path of other vessels, and it was never at any risk."
Ms Lynch said the vessels had been pulled from service as a precaution while the cause of the steering problem was investigated.
It is the second steering problem to hit the new Emerald Class fleet within days, with the Clontarf experiencing a failure on Sunday.
Ms Lynch maintained it was a rare event since the three new ferries began operating in November last year.
"In a week, it is two incidences, but since they've been in service, there have been very, very few. And in fact, there's only been three of this sort," she said.
Maritime Union of Australia deputy secretary Paul Garrett said there was "no such thing as a safe steering failure".
"Sooner rather than later, good luck will run out, and it'll fail in a close space quarters situation, and there'll either be a collision with the wharf or another vessel," Mr Garrett said.
He called for an independent safety investigation into issues with the second-generation Emerald Class ferries with questions also about their ability to handle large swells.
Transdev said the ferries had been cleared to operate within the Sydney Heads.
"There is no risk outside of very large swells [and] no ferry will go through the bigger swells," Ms Lynch said.
The union wants the four old Freshwater-class ferries to be returned to service immediately.
The NSW Opposition has committed to bringing back the iconic Manly ferries on weekdays if it wins the next election in March.
Ms Lynch said the 40-year-old ferries, two of which are used on weekends and public holidays, still had a place on the Harbour, but commuters were enjoying the change.
"Our new vessels have been a huge hit with the commuters who are really enjoying that fast and frequent service," she said.
Two services between Circular Quay and Manly were cancelled on Monday as a result of the steering problem, but services are now operating close to the timetable.
Ms Lynch apologised for the inconvenience caused to passengers.