Ind. Code § 8-21-9-24
The proceeds of the bonds of each issue shall be used solely for the payment of the cost of the airport facility or airport facilities for which the bonds have been issued, and shall be disbursed in the manner and under the restrictions, if any, as may be provided in the resolution authorizing the issuance of the bonds or in a trust agreement securing the issue. If the proceeds of the bonds of any issue, by error of estimates or otherwise, are less than the cost, additional bonds may in like manner be issued, subject to IC 8-9.5-5-8(6) (repealed), to provide the amount of the deficit, and, unless otherwise provided in the commissioner's executive order authorizing the issuance of the bonds or in the trust agreement securing the issue, are deemed to be of the same issue and entitled to payment from the same fund without preference or priority of the bonds first issued. If the proceeds of the bonds of any issue shall exceed the cost of the airport facility or airport facilities for which the bonds have been issued, the surplus shall be deposited to the credit of the sinking fund for the bonds. Prior to the preparation of definitive bonds, the department may, subject to IC 8-9.5-5-8(6) (repealed), issue interim receipts or temporary bonds, with or without coupons, exchangeable for definitive bonds when the bonds have been executed and are available for delivery. The department may also provide for the replacement of any bonds which shall become mutilated or shall be destroyed or lost.
IC 8-21-9-24