Michael Humberd stepped down Friday, less than three weeks after a 49 News investigation found how your tax dollars are being used by the airport. We uncovered that hundreds of thousands of dollars of your money aren't spent on anything. They serve only as a cushion to the airport checkbook.

Airport officials are being tight-lipped about Humberd's resignation. Humberd didn't explain why he was stepping down and the board members won't say why. By law, they're not required to.

Topeka's airport board held several closed-door meetings to discuss Micahel Humberd's job performance. They met in secret Dec. 18, 2007 and again twice last week before Humberd submitted a verbal resignation.

"It was a personnel matter and our meetings were discussions with him," said Sam Carkhuff, Metropolitan Topeka Airport Authority board member. "He decided that he wanted to resign from the board and we accepted it."

Carkhuff wouldn't comment on whether there were any questionable things Humberd was doing or if there was anything Humberd could've done better.

Humberd ducked our questions about why a portion of your property taxes went up nearly 30 percent in support of Topeka's airports. It was the first increase in nearly 10 years. Eventually Humberd told us the money was needed to pad the airport's checking account.

After Humberd resigned, we went to his house to ask him about it. There were people inside, but no one came to the door.

Now the board members will try to put Humberd behind them and focus on finding his replacement. Then eventually, Carkhuff said he hopes the board can find a way to save taxpayers money.

"The goal really is to get us off the tax rolls, if we can," said Carkhuff. "I don't know if that will ever happen, but that's our goal. We want to be self-sufficient and we're always working toward that."

It could take six months for the board to hire Humberd's replacement, Carkhuff said. The board will begin the process at its monthly board meeting Tuesday afternoon.