Air Chathams, which began Whanganui to Auckland flights in August, is continuing to push for a Chatham Islands runway expansion, despite its rising costs.
The airline, set up in 1984 for charter and scheduled services, introduced a service between Whanganui and Auckland in August after the route was abandoned by Air New Zealand.
General manager Duane Emeny said last year that a Boeing 737 service to the Chatham Islands was also on the cards, though that depended on whether a planned runway expansion went ahead.
The Chatham Islands Enterprise Trust was helping drive the project, which a government study initially billed at $35 million.
Mr Emeny said further investigation showed costs for the project, which would also allow increased travel within the Chathams, were likely to be higher.
He said the passenger jet option was the preferred economy of scale, but there would still be more flights if the runway expansion did not go ahead.
"There are more modern turbo prop aircraft which are more fuel efficient so operating costs lower but the capital costs are high - the equivalent of buying a Boeing 737.
"Our preference is a larger aircraft so we can grow the market," Mr Emeny said.
He said in the meantime the plan was to keep building on Whanganui and Whakatane services and introduce products such as a frequent flyer programme.
Mr Emeny said loadings on the Whanganui service had been about the target rate of 70 percent.