[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: 14CFR33.68]

[Page 746]
 
                     TITLE 14--AERONAUTICS AND SPACE
 
CHAPTER I--FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION
 
PART 33--AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES--Table of Contents
 
      Subpart E--Design and Construction; Turbine Aircraft Engines
 
Sec. 33.68  Induction system icing.

    Each engine, with all icing protection systems operating, must--
    (a) Operate throughout its flight power range (including idling) 
without the accumulation of ice on the engine components that adversely 
affects engine operation or that causes a serious loss of power or 
thrust in continuous maximum and intermittent maximum icing conditions 
as defined in appendix C of Part 25 of this chapter; and
    (b) Idle for 30 minutes on the ground, with the available air bleed 
for icing protection at its critical condition, without adverse effect, 
in an atmosphere that is at a temperature between 15 deg. and 30  deg.F 
(between -9 deg. and -1  deg.C) and has a liquid water content not less 
than 0.3 grams per cubic meter in the form of drops having a mean 
effective diameter not less than 20 microns, followed by a momentary 
operation at takeoff power or thrust. During the 30 minutes of idle 
operation the engine may be run up periodically to a moderate power or 
thrust setting in a manner acceptable to the Administrator.

[Amdt. 33-6, 39 FR 35466, Oct. 1, 1974, as amended by Amdt. 33-10, 49 FR 
6852, Feb. 23, 1984]