; and (2) the sustainable aviation fuel is refined or produced in the United States. (b) Blended fuel If the Secretary of Defense purchases sustainable aviation fuel that is blended with conventional jet fuel, the percentage of sustainable aviation fuel in such blend will be counted towards the percentage described in subsection (a). (c) Certification Before making a purchase under subsection (a), the Secretary of Defense or the Secretary concerned (as defined in section 101(a)(9) of title 10, United States Code) shall certify that the sustainable aviation fuel is suitable for use in aircrafts of the Department of Defense. (d) Waiver (1) In general Subject to the requirements of paragraph (2), the Secretary of Defense may waive the requirement under subsection (a) for reasons of national security, including the lack of available, qualifying sustainable aviation fuel. (2) Notice Not later than 30 days after issuing a waiver under this subsection, the Secretary shall submit to the congressional defense committees (as defined in section 101(a)(16) of title 10, United States Code) notice of the waiver. Any such notice shall include each of the following: (A) The rationale of the Secretary for issuing the waiver. (B) A certification that the waiver is in the national security interest of the United States. (e) Definitions The terms fully burdened cost and operational purposes have the meanings given such terms, respectively, in section 2922h of title 10, United States Code. 7. Federal aviation administration research (a) In general Section 911(a) of the FAA Modernization and Reform Act of 2012 ( 49 U.S.C. 44504 note) is amended— (1) by striking assist in the development and inserting the following: (1) assist in the development ; (2) by striking and other and inserting , other ; (3) by striking the period and inserting , and sustainable fuel that can be used without the need to blend with any other type of aviation fuel;