Aircraft refuellers at Melbourne Airport have begun a 24-hour strike but there has so far been no disruption to flights.
The refuellers, contracted to the Rivet Group, say they're struggling under increasing workloads and additional responsibilities, while pay and conditions are going backwards.
They have called a strike until 4am on Thursday, which is expected to mainly affect Qantas as well as freight companies Australia Air Express and DHL.
Qantas said flights today would operate as usual and that they were working with Melbourne Airport to minimise any disruption for passengers.
Transport Workers Union (TWU) assistant secretary Mem Suleyman said negotiations with the Rivet Group had so far failed.
"Throughout the process we've tried to reach a fair compromise, something that could help workers get through the cost of living crisis, but unfortunately through the process we've been disappointed," he said.
The union is calling on Qantas to step in and put pressure on the Rivet Group to improve pay and conditions for workers.
The TWU said workers had not had a pay rise in three years, while Qantas recently recorded a $1 billion half-year profit.
"We're asking them to intervene and talk to their contractor and engage in discussions with the workers, the workers that are refuelling their aircraft and let's get on with getting the public to their destinations," Mr Suleyman said.
Qantas said it had taken measures to ensure flights would operate as normal today, including flying a spare, fully fuelled A380 from Sydney to Melbourne to be used to fill up other aircraft.
The airline said aircraft flying into Melbourne would carry extra fuel to minimise the amount of refuelling at the airport.
Qantas said it did not have a direct contract with the Rivet Group, but had a fuelling contract with ExxonMobil, which subcontracts the refuelling of aircraft to Rivet.