Setting up Otago Air would involve floating a company to lease a plane and pilots, giving the city direct services to Australian cities, promoting the city and attracting tourism.
Funding would require 1000 people investing $1000 each for start-up capital of $1 million, an investment that could be returned in the form of air fares.
''If you are going to dream, dream big,'' he said.
''Nothing will happen if someone doesn't start the ball rolling,'' he said, adding he would put up the first $1000.
Former Kiwi Air chief executive Ewan Wilson, now a Hamilton city councillor, said the idea was not out of the question.
Kiwi Air collapsed after intense competition and Cr Wilson was later convicted of fraud.
He said yesterday the model he used could work.
That meant starting up a ''virtual airline'', as Kiwi Air did.
The company would lease planes and pilots from a nearby high-frequency airline with the necessary infrastructure and capacity.
''You then negotiate with them to operate your service, with your brand.''
That model meant less capital was required, and less time, because issues such as regulatory approval were the leasing airline's responsibility.
There was a cost, as that airline would take a profit.
But Cr Wilson said it could be done with a start-up cost of about $2 million.
As well, there was nothing to stop other cities left out of the international flight loop, such as Palmerston North and Hamilton, ''embracing'' the idea.
Regular flights might ''irritate'' existing carriers but might also prompt them to reinstate services.
''In a broader sense, that might not be so bad.''
Asked to respond to Mr Doherty's idea, Dunedin Mayor Dave Cull said Air New Zealand had said it had limited planes and pilots, and there was insufficient demand in Dunedin to push the city as a priority.
''That's the reality of it.''
However, the idea was ''not completely silly''.
Mr Cull said the Dunedin to Auckland route was the major problem for the city, because the schedule made it difficult to do business there in one day.
The high cost of the Dunedin to Christchurch route was ''Air New Zealand being quite cynical''. In a situation where there was no competition, ''they screw us'', Mr Cull said.
Mr Doherty said last night he was ''absolutely'' serious in a promise to put up the first $1000, and chair an inaugural meeting on the idea.
Air New Zealand did not respond to questions on the issues yesterday.