The Barnett Government has made no provision for extra early morning and late night train services when the new $2,2 billion airport rail line opens in 2020.
First trains typically begin at 5.30am and last trains depart at midnight, so rail services would not be available for many airline passengers with early departures or late arrivals.
Most flights that service fly-in, fly-out mining destinations leave Perth before 7am.
Transport Minister Dean Nalder said yesterday that the Government believed about 10 per cent of projected boardings at the airport station - 6100 a day when it opens in 2020 - would be FIFO workers.
Announcing at the weekend that the project would be tunnelled for its entire 8km, Mr Barnett said: "In particular this will be a boon for WA's thousands of fly-in, fly-out workers who will no longer have to drive to the airport and leave cars parked there for weeks on end."
Mr Nalder said Perth Airport's third runway would be completed by 2019, which would "change the window times" for FIFO flights.
"There is a need for us to review," he said of train service times. "We may need to look at commencing the services up to an hour earlier. Our analysis and patronage hasn't included that."
As political debate over the capital cost of the project continued to rage in Parliament, the Government revealed the line and its three stations would cost $37 million a year to run, offset by $14 million of revenue from fares, parking fees and advertising.
Opposition Leader Mark McGowan said the Government had to be more transparent.
"We just want to know how they arrived at the figure of $2.2 billion and we want to know how they decided on the route," he said. "The Premier should be able to answer those questions."