Qantas' decision to ground the entire Qantas fleet is "holding a knife to the nation's throat" and CEO Alan Joyce has "gone mad", the Australian and International Pilots Association (AIPA) says.
AIPA vice president Richard Woodward said the move was "premeditated, unnecessary and grossly irresponsible".
"Alan Joyce is holding a knife to the nation's throat," Captain Woodward said.
"No-one predicted this, because no one thought Alan Joyce was completely mad.
"This is a stunning overreaction. It is straight-up blackmail.
"I knew he was trying to kill Qantas, but I didn't know he wanted to do it this quickly.
"This is a grave and serious situation and the board should move to sack Mr Joyce immediately. This is the saddest day of my 25 years with Qantas."
He said AIPA's industrial action has been limited to making brief, positive in-flight announcements and wearing red ties.
"In response to this, Mr Joyce has now locked out every pilot working for Qantas. This is nothing short of crazy behaviour," he said.
"Mr Joyce is stranding thousands of Qantas passengers all across the globe so he can engage in his mad game of one-upmanship. All so he can pursue his delusion that Qantas should be an Asian airline, instead of an Australian one.
"We believe this action is unlawful and we are currently seeking legal advice.
" He has locked out short-haul 737 pilots who aren't even involved in any action at all.
Mr Woodward said this action would have been planned months in advance.
"Let's be clear about this: Mr Joyce would have planned to strand thousands of Qantas passengers all across the globe months ago," he said.
"To ground your entire fleet, when doing so is completely unnecessary, is not the act of a sane and reasonable person.
"He has snatched his ill-deserved millions on Friday and grounded the airline on Saturday. It's just tragic and unnecessary."