KEY POINTS:
Drivers have long known that slowing down on the highway gives more kilometres to the litre, now Air New Zealand has that found adding a few minutes to its journeys is also saving money.
The airline has saved about $30 million in fuel costs in the past 18 months partly by slowing its planes down.
Captain David Morgan, general manager airline operations, said it saved on fuel costs and also met the airline's "green" aims.
It is a trend being imitated by overseas airlines.
Southwest Airlines in the US started flying slower about two months ago, and believes it will save US$42 million ($59 million) in fuel this year by extending each flight by one to three minutes.
Captain Morgan said some long-haul Air New Zealand flights had been slowed by up to 20 minutes, but there was a limit.
"We are not going to subject people to 12-hour flights across the Tasman."
