"The captain met and debriefed customers in the terminal. They will now be transported by road to Wellington to continue their journeys," the spokesman said.
"Pilots followed standard operating procedures and requested emergency services be on standby for the landing."
People gather at Palmerston North airport as a flight is in trouble. Photo / Cameron Death
Cameron Death, who was waiting at Palmerston North airport for a flight, said there was "a lot of smoke" when the plane landed.
Passengers were immediately evacuated off the back of the plane and werestanding out on the runway, he said.
Death said ambulances and fire engines were out on the tarmac but nothing appeared to be happening to the plane.
People had gathered at the airport to watch.
Emergency services at the scene. Photo / Cameron Death
Earlier, he said everyone was cleared off an Air New Zealand flight due to leave for Christchurch.
He said the passengers were told that because of the emergency with the other plane, they needed them off the runway.
Fire Service shift manager Mike Wanoa said earlier emergency services were on site in case the heavy aircraft had problems when landing.
"The situation is that we have had a report of an aircraft with a problem and at the present time we are at the airport waiting for the aircraft," he said.
"There's a problem with unsafe landing gear."
The aircraft will remain on the runway until it has been inspected by engineers.
Customers booked to travel on the cancelled services can call the Air New Zealand Contact Centre on 0800 737 000 to rebook on an alternative service.
In light of the circumstances the airline is also offering full fare refunds, regardless of the fare type purchased.
If travel is not urgent or customers wish to request a fare refund there is no need to do so today as call centre demand may be higher than normal resulting in longer wait times.
