In November the Chronicle got confirmation from the airline that its 50-seater aircraft would be gradually introduced but that the bigger planes will mean a cut in the number of flights out of Wanganui.
The Beech planes that look after much of its regional network are being phased out on Air NZ's regional routes.
Air New Zealand currently operates four return trips every weekday between Wanganui and Auckland, with three return trips on a Saturday and four on a Sunday. But from February 2016, there will be three return services between the two ports on weekdays, two on Saturdays and two on Sundays because these services will be exclusively operated by larger 50-seat aircraft.
Christopher Luxon, Air New Zealand's chief executive, said the changes should bring cheaper air fares.
"By moving from a 19-seat aircraft to a 50-seat one, we expect to be able to reduce the average airfare by 15 per cent because of the better economies of scale achieved from distributing fixed operating cost across 50 passengers, rather than just 19," Mr Luxon said.
Last week the airline announced it would be adding more than 650,000 domestic seats in the 2016 financial year.
More flights and changing from Boeing 737s to more modern larger A320 aircraft, are behind the growth.
Most of the additional seats will be deployed on three key domestic routes - Auckland to Christchurch, Queenstown and Wellington. There will also be more capacity between Christchurch and Queenstown.
Cam Wallace, Air NZ's chief sales and commercial officer, said the number of seats available into and out of some regions is now set to increase by around 30 per cent compared with this financial year.
He said the Wanganui to Auckland capacity will increase by 35 per cent in the 2016 financial year.
