Sec. 11. (a) As long as any of the revenue bonds issued under section 16 of this chapter are outstanding, the municipality may not mortgage, pledge, otherwise encumber, sell, or dispose of any part of the property of a parking facility, except that it may sell or dispose of:
(1) equipment that is worn out and is to be replaced; or
(2) property that is no longer useful or profitable in the operation of the facility.
(b) The proceeds of a sale under subsection (a) shall be deposited in the fund or account for the payment of the principal of and interest on the revenue bonds.