[Code of Federal Regulations] [Title 14, Volume 2] [Revised as of January 1, 2006] From the U.S. Government Printing Office via GPO Access [CITE: 14CFR121.159] [Page 435] TITLE 14--AERONAUTICS AND SPACE CHAPTER I--FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PART 121_OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS--Table of Contents Subpart H_Aircraft Requirements Sec. 121.159 Single-engine airplanes prohibited. No certificate holder may operate a single-engine airplane under this part. [Doc. No. 28154, 60 FR 65927, Dec. 20, 1995]