Iowa State University President Steven Leath apologized Monday for using school airplanes for personal flight training and out-of-state medical appointments, announcing he has paid back costs of dozens of flights and would be more careful going forward.

Leath's remorse and decision to reimburse the university more than $19,000 for 55 questionable flights appeared to save his job leading Iowa's largest public university. Leath also pledged to sell the university's Cirrus SR-22 airplane, which he purchased for $498,000 with private donations in 2014 and used extensively for flight training and some trips to his North Carolina home.

The Board of Regents, which governs the school, met for 90 minutes in closed session to consider whether to retain Leath. Afterward, Board President Bruce Rastetter said he was disappointed and that "we can and must do better." But he commended Leath for taking responsibility, saying his corrective actions "eliminate any questions about the personal benefit that he may have received by using the university aircraft."

"The president deserves our continued trust and support," Rastetter said.

An audit released Monday found the university and its private foundation spent millions buying and flying planes during Leath's five-year tenure.

Leath, a pilot, announced that he paid back the university for 52 local flights related to the training, proficiency and certification required for him to be covered under the university's aviation insurance policy. He said he thought it would benefit the university to have him be able to fly himself, but can now see how it would be considered a "personal benefit."

He said he also refunded costs for two trips to Rochester, Minnesota, for medical appointments at Mayo Clinic. He said he took a university plane to save time, but the audit questioned whether the flights were appropriate and said the board should seek a refund if not.

Leath said he also paid back some costs of a 2014 trip in which a plane twice landed in Horseheads, New York, to pick up and drop off his brother and sister-in-law on the way to and from an Iowa State NCAA tournament basketball game. Leath said the stops didn't add costs, but it was inappropriate to invite his brother along. The audit found the plane didn't need to stop to refuel there on the way home, as Leath initially claimed.

Leath apologized for problems detailed in the audit, which found the annual budget of the university's flight services department shot up 125 percent to $880,000 during his tenure.

"I recognized that I used the university planes more frequently than was absolutely necessary, and should have been more transparent about some of the use," Leath said, vowing to be a "better, more conscientious president."

Leath previously said the university was considering shutting down the flight services department, which employs three pilots. In addition to buying the Cirrus for $498,000, the university's foundation spent $3.4 million to acquire and upgrade a larger King Air in 2014 used for athletic recruiting and fundraising.

The audit revealed the university spent $35,000 for Leath to take charter flights on private planes, including two flights home from business trips when commercial flights were cancelled.

The board's chief auditor, Todd Stewart, said some of Leath's flights fall into a gray area where it's not clear whether they would be allowed by university policy. He said the university should approve a policy spelling out clearly when it is appropriate to use a university plane or private charter.

Before Monday, Leath had already reimbursed $17,500 for damage resulting from a hard landing in the Cirrus, and $4,600 for four trips to North Carolina that had major personal components to them. Leath has argued that those trips were justified because he performed some university meetings during each. But the audit found that one meeting was cancelled for an August trip to North Carolina.

The board ordered the audit in October after The Associated Press revealed that Leath made the hard landing in Illinois while flying home from a North Carolina vacation. Leath didn't inform the university's risk management office about the landing as required by policy, and that office wasn't involved in the decision to pay for repairs rather than file an insurance claim, Stewart said.