Notwithstanding any other provision of this chapter, the Secretary is authorized to insure loans made to cover the operating losses of certain projects that have existing project mortgages insured by the Secretary. Insurance under this subsection shall be in the Secretary’s discretion and upon such terms and conditions as the Secretary may prescribe, and shall be provided in accordance with the provisions of this subsection. For purposes of this subsection, the term “operating loss” means the amount by which the sum of the taxes, interest on the mortgage debt, mortgage insurance premiums, hazard insurance premiums, and the expense of maintenance and operation of the project covered by the mortgage, exceeds the income of the project.