The US airlines' new era of profitablity offers a new basis for sustainability. What will unions do?

All of the large US airlines delivered profits in 2014, with many achieving a return on invested capital well in excess of 10% including Delta Air Lines' 20.7% return and Alaska Air Group's 18.6% ROIC.

It is a far cry from a decade ago when Delta and Northwest were on the verge of entering Chapter 11 reorganisation and United was about to mark its third year of bankruptcy protection.

At that time, ROIC was not even on the radar of airline executive teams that were struggling to ensure the short term survival of their respective entities.

A big issue in this new environment is how labour will view the new profitability - and how the different airline managements are responding. CAPA's Americas Aviation Summit, Las Vegas, 27/28 April, includes a powerful panel looking at the role of pilots in the airline business.