492 (3) after action on those policies and regulations by the Secretary, act as the agent of the Secretary in carrying them into effect, (g) I n addition to the functions and duties performed by it for the Department of the Army, the National Guard Bureau shall perform similar functions and duties for the Department of the Air Force, and shall be the channel of communication between the Department of the Air Force and the States and Territories, Puerto Rico, the Canal Zone, and the District of Columbia on all matters affecting the Air National Guard. § 8034. Chief of Staff: appointment; duties (a) The Chief of Staff shall be appointed by the President, by and with the advice and consent of the Senate, from the general officers of the Air Force. H e serves during the pleasure of the President, but not for more than four years unless reappointed by the President, by and with the advice and consent of the Senate. (b) The Chief of Staff, while so serving, has the grade of general without vacating his regular or reserve grade, and is counted as one of the officers authorized to serve in a grade above lieutenant general under section 8066 of this title. (c) Except as otherwise prescribed by law and subject to section 8012 (c) and (d) of this title, the Chief of Staff performs his duties under the direction of the Secretary of the Air Force, and is directly responsible to the Secretary for the efficiency of the Air Force, its preparedness for military operations, and plans therefor. (d) The Chief of Staff shall— (1) preside over the Air Staff; (2) send the plans and recommendations of the Air Staff to the Secretary, and advise him with regard thereto; (3) after approval of the plans or recommendations of the Air Staff by the Secretary, act as the agent of the Secretary in carrying them into effect; (4) exercise command over the air defense command, the strategic air command, the tactical air command, and such other major commands as may be established under section 8074(c) of this title; (5) supervise all other members and organizations of the Air Force; (6) perform the duties prescribed for him by sections 141 and , 171 of this title and other provisions of law; and (7) perform such other military duties, not otherwise assigned by law, as are assigned to him by the President. §8035. Vice Chief of Staff; Deputy Chiefs of Staff: succession to duties of Chief of Staff and Vice Chief of Staff (a) The Vice Chief of Staff and the Deputy Chiefs of Staff shall be general officers detailed to those positions. (b) If the Chief of Staff is absent or disabled or if that office is vacant, the officer who is highest on the following list and who is not absent or disabled shall, unless otherwise directed by the President, perform the duties of the Chief of Staff until a successor is appointed or the absence or disability ceases: (1) The Vice Chief of Staff.