; and (B) such experience includes at least one full tour of duty in a joint duty assignment (as defined in section 664(d) of this title) as a general officer. (4) The President may waive paragraph (3) in the case of an officer if the President determines such action is necessary in the national interest. (b) Grade The Chief of Staff of the Space Force, while so serving, has the grade of general without vacating the permanent grade of the officer. (c) Relationship to the Secretary of the Air Force Except as otherwise prescribed by law and subject to section 9013(f) of this title, the Chief of Staff of the Space Force performs the duties of such position under the authority, direction, and control of the Secretary of the Air Force and is directly responsible to the Secretary. (d) Duties Subject to the authority, direction, and control of the Secretary of the Air Force, the Chief of Staff of the Space Force shall— (1) preside over the Space Staff; (2) transmit the plans and recommendations of the Space Staff to the Secretary of the Air Force and advise the Secretary with regard to such plans and recommendations; (3) after approval of the plans or recommendations of the Space Staff by the Secretary of the Air Force, act as the agent of the Secretary in carrying them into effect; (4) exercise supervision, consistent with the authority assigned to commanders of unified or specified combatant commands under chapter 6 of this title, over such of the members and organizations of the Space Force and the Air Force as the Secretary of the Air Force determines; (5) perform the duties prescribed for the Chief of Staff by sections 171 and 2547 of this title and other provisions of law