A looming strike will impact FIFO workers and holiday makers, unless pilots reach an agreement with Qantas.
More than 200 pilots in Western Australia are battling the airline for a pay rise, and say if they don't get it by Wednesday they're prepared to walk off the job.
The pilots work for Network Aviation, which is a subsidiary company wholly owned by Qantas.
They fly through Western Australia domestically, so there are concerns the strikes could impact FIFO workers and school holiday travellers.
Qantas has brought in backup pilots from the east coast, but has already cancelled 50 per cent of flights for Wednesday in anticipation of the strike.
"Customers who won't be able to travel on Wednesday because of the work stoppages are being contacted to discuss alternative travel options," Qantas said in a statement.
"Customers can request a full refund if they no longer wish to fly."
The Australian Federal of Air Pilots said some of its members were being paid below what was legally allowed. The old pay agreement ran out three years ago.
