Air New Zealand says a Boeing 737 plane forced to make an emergency landing in Wellington is expected to be back in service on Thursday morning.
The airline says a rubbery odour was smelled in the aircraft during a flight from Auckland to Christchurch on Wednesday.
Fire fighters were put on stand-by, but Flight NZ 535 landed safely at 3.35pm.
Air New Zealand says engineers found a fault with a rubber seal on an air conditioning pack.
The units are heated which produced the smell in the cabin. The seal has been replaced.