The Secretary of Defense may establish a program (in this section referred to as the “travel program”) to provide transportation on Department of Defense aircraft on a space-available basis to the categories of individuals eligible under subsection (c).

If the Secretary makes a determination to establish the travel program, the Secretary shall prescribe regulations for the operation of the travel program not later than one year after the date on which the determination was made. The regulations shall take effect on that date or such earlier date as the Secretary shall specify in the regulations.

The Secretary of Defense shall operate the travel program in a budget-neutral manner.

No additional funds may be used, or flight hours performed, for the purpose of providing transportation under the travel program.

Members of the armed forces on active duty.

Members of the Selected Reserve who hold a valid Uniformed Services Identification and Privilege Card.

Retired members of a regular or reserve component of the armed forces, including retired members of reserve components who, but for being under the eligibility age applicable under section 12731 of this title, would be eligible for retired pay under chapter 1223 of this title.

Subject to subsection (f), veterans with a permanent service-connected disability rated as total.

Such categories of dependents of individuals described in paragraphs (1) through (3) as the Secretary shall specify in the regulations under subsection (a), under such conditions and circumstances as the Secretary shall specify in such regulations.

Such other categories of individuals as the Secretary, in the discretion of the Secretary, considers appropriate.

in the sole discretion of the Secretary, establish an order of priority for transportation under the travel program for categories of eligible individuals that is based on considerations of military necessity, humanitarian concerns, and enhancement of morale;

give priority in consideration of transportation under the travel program to the demands of members of the armed forces in the regular components and in the reserve components on active duty and to the need to provide such members, and their dependents, a means of respite from such demands; and

implement policies aimed at ensuring cost control (as required by subsection (b)) and the safety, security, and efficient processing of travelers, including limiting the benefit under the travel program to one or more categories of otherwise eligible individuals if considered necessary by the Secretary.

Notwithstanding subsection (d)(1), in establishing space-available transportation priorities under the travel program, the Secretary of Defense shall provide transportation for an individual described in paragraph (2), and a single dependent of the individual if needed to accompany the individual, at a priority level in the same category as the priority level for an unaccompanied dependent over the age of 18 traveling on environmental and morale leave.

If an individual described in subsection (c)(3) is a retired member of a reserve component who is ineligible for retired pay under chapter 1223 of this title by reason of being under the eligibility age applicable under section 12731 of this title, paragraph (1) applies to the individual only if the individual is also enrolled in the TRICARE program for certain members of the Retired Reserve authorized under section 1076e of this title.

The requirement to provide transportation on Department of Defense aircraft on a space-available basis on the priority basis described in paragraph (1) to individuals covered by this subsection applies whether or not the travel program is established under this section.

In this subsection, the terms “primary care provider” and “specialty care provider” refer to a medical or dental professional who provides health care services under chapter 55 of this title.

Travel may not be provided under this section to a veteran eligible for travel pursuant to subsection (c)(4) in priority over any member eligible for travel under subsection (c)(1) or any dependent of such a member eligible for travel under this section.

The authority in subsection (c)(4) may not be construed as affecting or in any way imposing on the Department of Defense, any armed force, or any commercial company with which they contract an obligation or expectation that they will retrofit or alter, in any way, military aircraft or commercial aircraft, or related equipment or facilities, used or leased by the Department or such armed force to accommodate passengers provided travel under such authority on account of disability.

The authority in subsection (c)(4) may not be construed as preempting the authority of a flight commander to determine who boards the aircraft and any other matters in connection with safe operation of the aircraft.