The NDP's Deron Bilous said the charges include near-empty private flights, deadhead flights and short-haul excursions when there were plentiful commercial options.
Bilous said the bills speak to the core of Prentice's cornerstone campaign promise to clean up the extravagant spending of former premier Alison Redford.
"He is talking and boasting about how he is going to be very, very responsible with flights and he prefers commercial flights," Bilous told a legislature news conference Wednesday.
"OK, Mr. Prentice, that's what you say, yet the proof is actually quite the opposite."
Bilous said the documents show that, in one case, Prentice had a plane flown empty from Ottawa to Toronto so that he could fly back to Ottawa alone.
In another case, Prentice flew himself and two staff to Norway for almost $42,000, when commercial flights were about half that amount.
Prentice, in a news release, did not address the specific flights or the $400,000 global cost, but said he followed the rules.
"I only used government aircraft in order to carry out my official duties, and only when commercial alternatives were not available at the time that I had to travel to complete those official duties," he said.
"The federal government has very clear and stringent rules about use of government aircraft.
"It is only permitted when there is no commercial alternative at the time of travel and when proposed travel has been approved by the Prime Minister’s Office and deemed necessary in order to carry out official government business.
"During my time in Ottawa, I always followed these rules implicitly.”
Prentice is one of three candidates vying to replace Redford as Progressive Conservative leader and premier.
The 57-year-old is the former Conservative MP for Calgary Centre North.
He served in Prime Minister Stephen Harper's cabinet in three portfolios: Indian and Northern Affairs, Industry and Environment.
He left cabinet in November 2010 to take a job as an executive with the CIBC.
Redford resigned as premier in March amid revelations of exorbitant and wasteful spending on herself and inner circle, including $45,000 in flights to take her and an assistant to South Africa for Nelson Mandela's funeral.
It was also revealed Redford used government planes for personal and party political trips, and for shuttling family and friends around.
Alberta's auditor general is reviewing the use of the government fleet to see if it brings value for money.
Prentice has said regardless of the auditor general's findings, he and his government members would use commercial options where available, particularly in the busy Edmonton-Calgary corridor.
He would also look at other options for politicians to reach remote areas, such as chartering private planes rather than owning them.
He also said he will cancel the current practice that allows family members of government legislature members to fly on government aircraft.
The government fleet consists of three Beechcraft King Air planes and a 30-seat Dash 8. It provides employment for 23 people, including 13 pilots, at a cost of $4.6 million a year.
Former Alberta cabinet ministers Ric McIver and Thomas Lukaszuk are also campaigning for the top job.
McIver has said he'll wait for the auditor general's report before deciding on flight policy.
Lukaszuk has yet to announce a policy but has said he rarely used government aircraft when he was in cabinet.
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