14 CFR §119.55

1. (a)The Administrator may authorize a certificate holder that is authorized to conduct supplemental or on-demand operations to deviate from the applicable requirements of this part, part 117, part 121, or part 135 of this chapter in order to perform operations under a U.S. military contract.
2. (b)A certificate holder that has a contract with the U.S. Department of Defense's Air Mobility Command (AMC) must submit a request for deviation authority to AMC. AMC will review the requests, then forward the carriers' consolidated requests, along with AMC's recommendations, to the FAA for review and action.
3. (c)The Administrator may authorize a deviation to perform operations under a U.S. military contract under the following conditions—
   1. (1)The Department of Defense certifies to the Administrator that the operation is essential to the national defense;
   2. (2)The Department of Defense further certifies that the certificate holder cannot perform the operation without deviation authority;
   3. (3)The certificate holder will perform the operation under a contract or subcontract for the benefit of a U.S. armed service; and
   4. (4)The Administrator finds that the deviation is based on grounds other than economic advantage either to the certificate holder or to the United States.
4. (d)In the case where the Administrator authorizes a deviation under this section, the Administrator will issue an appropriate amendment to the certificate holder's operations specifications.
5. (e)The Administrator may, at any time, terminate any grant of deviation authority issued under this section.