Defence Minister David Johnston has justified chartering a luxury RAAF jet to fly MPs from Perth to Canberra by saying the practice allowed WA Federal politicians more "family time".
But the minister insisted it would cost taxpayers even more if MPs took commercial flights instead.
Senator Johnston ordered an RAAF 737 Boeing business jet to fly empty to Perth on Sunday to take three ministers, several MPs, their wives and children to Canberra for today's opening of Parliament.
Although 26 passengers were on the manifest, there were several empty seats because of last-minute cancellations, including from MPs Dennis Jensen and Steve Irons and Mr Irons' wife Cheryle.
In fuel costs alone, the flight cost taxpayers $30,000, including the empty Canberra-Perth leg.
One-way business class tickets to Canberra cost about $2000 from Perth using Qantas, though Transport Workers Union national secretary Tony Sheldon pointed out that if MPs went economy on Virgin, their fares would be as low as $255.
"There's even a complimentary meal onboard," he said.
Chartering a Boeing 737 would cost at least $15,000 an hour, according to industry estimates.
Originally scheduled to leave at 2pm on Sunday, it eventually flew out of Perth at 4pm, about 25 minutes after the last direct commercial flight to Canberra, QF718, departed.
Special Minister of State Michael Ronaldson, who oversees MPs' entitlements, yesterday referred questions about the flight to Senator Johnston.
Senator Johnston said the Perth-Canberra VIP flight on the Sunday before a parliamentary sitting week was common under Labor.
"It's used for all WA members so that on Sunday afternoon Gary Gray, Stephen Smith, myself and others would go to Canberra on the VIP, giving us a few extra hours of family time," he told Seven News.