N.H. Rev. Stat. § 12-G:19

Any bonds issued pursuant to RSA 12-G:17-28 may be issued pursuant to lines of credit or other banking arrangements under such terms and conditions not inconsistent with this chapter, and under such agreements with the purchasers or makers thereof, as the board may determine to be in the best interests of the authority. In addition to other security provided herein or otherwise by law, bonds issued by the authority pursuant to RSA 12-G:17-28 may be secured, in whole or in part, by insurance or by letters or lines of credit or other credit facilities issued to the authority by any bank, trust company, or other financial institution, within or without the state, and the authority may make any pledge, mortgage, assignment, or security interest in respect of its airport property and revenues other than division revenues as security for the reimbursement by the authority to the issuers of such letters or lines of credit, insurance, or credit facilities or any payments made thereunder.