A 30-year Qantas veteran currently undergoing radiotherapy for cancer is among a group of workers taking the airline to the Federal Court today to try and reverse its decision to deny sick leave during stand down.

Air New Zealand and Qantas are the two most reputable businesses in Australia, according to the latest release of a long-standing survey.

Qantas shares spiked within minutes of Virgin Australia entering voluntary administration on Tuesday morning -- but have subsequently slumped after interest grew in acquiring its rival.

Virgin Australia has had a particularly turbulent couple of days, from initially demanding a federal government bail-out, to state government hostility over the location of their HQ, to collapsing into voluntary administration.