ASEAN's goal of achieving a single aviation market, or 'Open Sky', via liberalisation of regional air transportation by the end of this year, faces a number of major obstacles, according to an expert.
These include non-acceptance by key member states, an incomplete agenda, and the need for further relaxations in terms of market access and ownership and control rules.
"Failure by ASEAN nations' to forge a truly single [aviation] market and a common negotiating [position] would cause risk disadvantaging airlines from larger markets such as China," Alan Khee-Jin Tan, an aviation scholar at the National University of Singapore's Faculty of Law, said recently at an open-sky conference in Bangkok.
He said that despite the problems currently being faced, all member states would in time get down to meaningful discussions on developing a truly single aviation market, and also build a common direction for negotiating with other countries.
This would be entirely in line with the broader ambition of achieving the ASEAN Economic Community, which is also scheduled to be implemented at the end of this year, he said.
Tran Dong Phuong, ASEAN's director of finance, industry and infrastructure, told the conference that all nations in the region were approaching "fifth-freedom" agreement, including emerging Myanmar, Laos and Cambodia.
The regional grouping's fifth freedom is the right to fly between two foreign countries on a flight originating or ending in one's own country.
Some members are now talking about the next step, an open sky - the seventh freedom - which would allow an airline to operate anywhere in the region, while crew and staff would also be able to work in any country throughout ASEAN.
According to Tan, the reality however is that progress is likely to be slow, as big players like Indonesia continue to hold out on relatively modest issues like third- and fourth-freedom passenger rights, and even air-freight services.
The huge difference in airline sizes and competitiveness within the region is clear for all to see, he added, citing smaller countries such as Singapore and Malaysia.
"Further liberalisation [domestic operations and ownership and control rules, for the seventh freedom] seems even more distant," he added.
However, the academic said there were several factors that could continue the momentum for change beyond 2015.
There is the confidence of Indonesian carriers such as Garuda and Lion Air as they expand their services, and increase their competitiveness and passenger numbers.
There may come a time that they will seek further liberalisation and argue against limited rights that hinder their expansion overseas, he explained.
This in fact happened recently when Indonesian carriers wanted to expand operations to Singapore, but came up against their government, which had to renegotiate bilateral capacity, he said.
Another factor is the pressure from provincial governments, tourism authorities and the business community for granting direct aviation access to regional cities, which has already been seen in the Philippines - and to a lesser extent in Indonesia.