Etihad Airways is once again flexing its muscles, extending its existing deal with in-flight entertainment provider Global Eagle Entertainment (GEE) to five of its Etihad Airways Partners.

The airlines who will start showing content from Nasdaq-listed GEE on flights are Jet Airways, Airberlin, Alitalia, Air Seychelles and Air Serbia.

GEE's statement says it will "provide an enhanced and consistent passenger experience while also generating cost efficiencies across participating carriers."

"Cost efficencies" are one operational benefit of the partner group - details about the specifics of the GEE deal are thin on the ground but it would be surprising if "economies of scale" were not in play, particularly as Etihad has used GEE for the past decade or so.

Etihad Airways Partners is more than just an alliance with codeshares - Etihad has an equity stake in each of the carriers and has been building up the network for a number of years.

The group is seen by many international aviation ownership law geeks as an effective way for Etihad to own stakes in airlines while outright ownership remains off-limits.

This close working relationship between Etihad and its partners stepped up a gear last month with the announcement that Etihad and the partner airlines have jointly raised US$700 million. CAPA has just published a detailed look at the theory and practice of the Etihad Airways Partners in light of the combined raise.

Its analysis says that Etihad Airways Partners is "looking and feeling more and more like a consolidated group of companies under common ownership and control".

The CEOs of the partner carriers met late last month in Rome to shoot the breeze on the opportunities available. A press release ran through some of options discussed and noted that "the airlines also collaborate on the sourcing of IT platforms."

Enter stage left, Sabre.

Etihad is one of Sabre's biggest airline customers - when the ten-year deal with Sabre Airline Solutions was announced in 2011 it was valued at one billion dollars. Since then, Sabre has built up its own commercial arrangements with the partners - Airberlin for example is migrating to SabreSonic next year with Alitalia and Air Seychelles making similar announcements this year.

Whether or not Sabre and Etihad are working towards getting all the partner airlines onto the same platform is unclear, but it would make sense if Etihad wants to be at the centre of its own global airline conglomerate.

And with Emirates continuing to expand and invest, individually and via its partners, it would make sense for Sabre as well.