IT costs taxpayers £86 every time a passenger uses the Cardiff to Anglesey air service, new figures have shown.
The cost of a fare, meanwhile, starts from £19 with the maximum cost just over £50.
The service is currently subsidised to the tune of £1.2 million per year. Passenger numbers are down 43 per cent from their 2008/9 peak.
AMs on the National Assembly's public accounts committee have been delving into the finances of the Welsh Government-backed operation.
Committee chairman, AM Darren Millar, said: "The subject matter is of significant public interest and, no matter what the future arrangements may be, we hope that our findings and recommendations will assist in securing value for money for taxpayers."
The recommendations include the Welsh Government using an independent source to verify data on passenger numbers, an explicit requirement in any future tender for a comprehensive marketing programme to be undertaken by the successful bidder, and information to be collated on the reasons for passenger travel.
The service is currently operated by Links Air, with Citywing dealing with ticketing arrangements and marketing.
Committee member Aled Roberts AM said: "The Welsh Liberal Democrats would scrap this wasteful and polluting subsidy. This costly venture does little to address the real problems of public transport links between north and south."