5 U.S.C. § 5709
Air evacuation patients: furnished subsistence
Notwithstanding any other provision of law, and under regulations prescribed under section 5707 of this title , an employee and his dependents may be furnished subsistence without charge while being evacuated as a patient by military aircraft of the United States.
(Added Pub. L. 91–481, § 1(1) , Oct. 21, 1970 , 84 Stat. 1081 .)