http://www.apd.army.mil/. Please look under the Official Publications Section for "New Releases". The publication number is Army Directive 2005-001 dated 07 January 2005.
This document implements specified policies and procedures provided by the Joint Travel Regulations and Joint Federal Travel Regulations (JTR/JFTR), and DoD 4500.56, DoD Policy on the Use of Government Aircraft and Air Travel (1997). Of particular note are the recent changes to the JTR, Chapter 2, Section C2204, Commercial Air Transportation. These changes raise the level of approval of premium class travel and strengthen the description of circumstances when premium class travel may be used to more clearly show it is an exceptional circumstance and not a common practice.