CFR > Title 14 - Aeronautics and Space > CHAPTER I—FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION > SUBCHAPTER B—PROCEDURAL RULES (parts 11 to 17) > PART 13—INVESTIGATIVE AND ENFORCEMENT PROCEDURES > SUBPART D—Rules of Practice for FAA Hearings (§13.31 to §13.63) > 13.31—Applicability.