[Code of Federal Regulations]
[Title 14, Volume 1]
[Revised as of January 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 14CFR33.37]

[Page 740]
 
                     TITLE 14--AERONAUTICS AND SPACE
 
CHAPTER I--FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION
 
PART 33--AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES--Table of Contents
 
   Subpart C--Design and Construction; Reciprocating Aircraft Engines
 
Sec. 33.37  Ignition system.

    Each spark ignition engine must have a dual ignition system with at 
least two spark plugs for each cylinder and two separate electric 
circuits with separate sources of electrical energy, or have an ignition 
system of equivalent in-flight reliability.