41 CFR § 301-10.262 - How will my agency authorize travel on Government aircraft?
Your agency will authorize your travel on Government aircraft as follows:
(a) Required use travelers. Your agency's senior legal official or his/her principal deputy must authorize your required-use travel on a trip-by-trip basis, in advance, in writing, and in compliance with the agency's written policies describing the special circumstances under which the agency will require a traveler to use Government aircraft, unless—
(1) You are an agency head and the President has determined that all your travel (or your travel in specified categories) qualifies as required-use travel; or
(2) You are not an agency head, and your agency head has determined in writing that all of your travel, or your travel in specified categories, qualifies as required-use travel. Such written explanation must state the specific basis for the determination.
In an emergency situation, prior verbal approval for required-use travel with an after-the-fact written authorization is permitted.
(b) Senior Federal officials. If you are a senior Federal official, your agency's senior legal official or his/her principal deputy must authorize all your travel on Government aircraft in advance and in writing, except for required use travel authorized under paragraphs (a)(1) and (a)(2) of this section. In an emergency situation, prior verbal approval with an after-the-fact written authorization by your agency's senior legal official is permitted. Senior Federal officials who are crewmembers or qualified non-crewmembers on a flight in which they are also traveling (i.e., being transported from point to point) are considered travelers and must be authorized to travel on Government aircraft according to this paragraph.
(c) Non-Federal travelers. If you are a non-Federal traveler, the senior legal official or his/her principal deputy in the agency sponsoring your travel must authorize you to fly on Government aircraft in advance and in writing. In an emergency situation, prior verbal approval with an after-the-fact written authorization by your sponsoring agency's senior legal official is permitted.
(d) All other Federal travelers. Your designated travel-approving official (or anyone to whom he/she delegates this authority), who must be at least one organizational level above you, must authorize your travel on Government aircraft, in advance and in writing. Prior verbal approval with an after-the-fact written authorization by your agency's designated travel approving official is permitted in an emergency situation. If you hold a blanket travel authorization for official travel that authorizes travel on Government aircraft, it must define the circumstances that must be met for using Government aircraft and must comply with this regulation and any additional agency policies. Travel on Government aircraft that does not meet the circumstances specified in the blanket travel authorization must be authorized on a trip-by-trip basis in accordance with this regulation and other applicable agency policies. Check with your designated travel approving official for information on your agency's policy.