Europe’s much-vaunted single aviation market remains an incomplete initiative, costing airlines €37 billion ($41 billion) per year in terms of disunity in legislation and application of regulations, according to an independent air transport research group.

Half of this figure – some €17.4 billion – could be saved by implementing an updated regulatory framework for the Single European Sky programme, says a study from a University of Bergamo specialist centre.

Other savings potentially arise from taxation, airport charge, and border-control changes.

The International Centre for Competitiveness Studies in the Aviation Industry has conducted the analysis, Cost of Non-Europe in Aviation, for the industry group Airlines for Europe, A4E, which is holding its annual aviation summit in Brussels this week.

A4E says the European Union’s ‘open skies’ competitive arena and reduction of air fares remain crucial achievements, after the single aviation market emerged in 1992, but the absence of a seamless airspace structure and revised regulatory framework is still costing airlines substantial sums.

The €17.4 billion figure is more than treble the €5 billion saving estimate put forward by the European Commission in 2013, says A4E managing director Thomas Reynaert.

“[Full Single European Sky] implementation would allow airlines to put these funds to better use, for example investing them in new aircraft technologies or sustainable aviation fuels,” he says.

The ICCSAI study looked at known bottlenecks in the current system as well as new areas that have not been previously quantified.

Improvements across five key areas would strengthen the competitiveness of Europe’s aviation sector over the long term, it finds.

While patching the airspace inefficiencies which fall under the Single European Sky is the primary cost concern, another €16.7 billion could be saved by abolishing “unilateral” aviation taxes which distort the market, says A4E.

More effective regulation and better enforcement of the European Union’s directive on airport charges could provide €2 billion in savings annually, it adds, while inefficiencies in border controls, inadequate staffing, passenger delays, and inconsistency in customs rules implementation are costing over €1 billion.

“Aviation is easily impacted by disruptions in the value chain and therefore requires a holistic approach,” says Reynaert.

“We call on the European Commission to take the necessary steps to finally and fully complete the single market for aviation in Europe to unlock these savings for airlines and travellers alike.”

A4E leaders attending the Brussels summit insisted that such measures were crucial to ensuring the success of environmental efforts in the industry.

”Failing is simply not an option,” says A4E chairman and Air France-KLM chief Benjamin Smith.

A4E carriers are to invest €169 billion in aircraft technologies which, on average, are 25% cleaner and less noisy than their predecessors, the group claims.

British Airways and Iberia parent IAG’s chief, Willie Walsh, told the summit that the Boeing 737-200s he had flown decades ago were effectively following the same flightpaths that currently exist, and that little had changed in the last 40 years.

“Quite honestly, that is a scandal,” he says.

“Airlines are doing their share. But in some areas, like air traffic management, we need action from other parts of the industry and EU leaders in order to succeed. Modernisation of European airspace is both urgent and long overdue.”

Walsh says some 25 million tonnes of carbon emissions per year could be cut through a redesign of airspace and creation of an integrated system of flightpaths, adding: “Creation of a Single European Sky has been debated for 20 years – we cannot afford to wait any longer.”