A busy Air New Zealand service to the Cook Islands has turned back for Auckland two hours into its journey.

The Dreamliner service NZ946, which had departed for Rarotonga Airport, reported the divert back to New Zealand on Wednesday morning around 11am.

After departing Auckland late around 9.40am, the plane made the divert when it was around two-thirds of the way through the 3000km trip.

Arrivals boards at Rarotonga Airport still showed the service as being “on time”.

The Herald understands the diversion was not weather-related, and relates to a matter separate from the delay on the tarmac while the flight was departing Auckland Airport.

A spokesperson for the airline said the redirect was due to a deflated tyre detected en route to Rarotonga.

Captain David Morgan chief operational integrity and safety officer for the airline said the flight “was redirected back to Auckland this afternoon due to low tyre pressure.”

This tyre change was to be conducted by Air New Zealand engineers who were waiting for the plane’s return to Auckland.

Air New Zealand hoped passengers and the aircraft would continue on to Rarotonga later this afternoon.

“We apologise for the inconvenience and appreciate our customers patience,” said captain Morgan.

The 25 minute delay before departure was to offload bags, belonging to a passenger who failed to turn up for the flight.

NZ946 was rerouted back to Auckland this morning after being unable to land at Rarotonga. Photo / Flight Radar

What happens if your plane gets a flat tyre?

A Boeing 787 Dreamliner has eight tyres for service. While flights move very little on their tyres, there are key parts of their journey: takeoff and landing.

A single Michelin Air X tyre for a Beoing narrow-body plane can cost upwards of $7,000 according to Airways magazine.

It is standard procedure for emergency services to be on standby for planes diverting due to low tyre pressure.

NZ946 is expected to land before 3pm.