[Code of Federal Regulations] [Title 40, Volume 18] [Revised as of July 1, 2003] From the U.S. Government Printing Office via GPO Access [CITE: 40CFR87.81] [Page 12] TITLE 40--PROTECTION OF ENVIRONMENT CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PART 87--CONTROL OF AIR POLLUTION FROM AIRCRAFT AND AIRCRAFT ENGINES--Table of Contents Subpart H--Test Procedures for Engine Smoke Emissions (Aircraft Gas Turbine Engines) Sec. 87.81 Fuel specifications. Fuel having specifications as provided in Sec. 87.61 shall be used in smoke emission testing.