[Code of Federal Regulations]
[Title 14, Volume 1]
[Revised as of January 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 14CFR23.49]

[Page 179]
 
                     TITLE 14--AERONAUTICS AND SPACE
 
CHAPTER I--FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION
 
PART 23--AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER 
CATEGORY AIRPLANES--Table of Contents
 
                            Subpart B--Flight
 
Sec. 23.49  Stalling period.

    (a) VSO and VS1 are the stalling speeds or the 
minimum steady flight speeds, in knots (CAS), at which the airplane is 
controllable with--
    (1) For reciprocating engine-powered airplanes, the engine(s) 
idling, the throttle(s) closed or at not more than the power necessary 
for zero thrust at a speed not more than 110 percent of the stalling 
speed;
    (2) For turbine engine-powered airplanes, the propulsive thrust not 
greater than zero at the stalling speed, or, if the resultant thrust has 
no appreciable effect on the stalling speed, with engine(s) idling and 
throttle(s) closed;
    (3) The propeller(s) in the takeoff position;
    (4) The airplane in the condition existing in the test, in which 
VSO and VS1 are being used;
    (5) The center of gravity in the position that results in the 
highest value of VSO and VS1; and
    (6) The weight used when VSO and VS1 are being 
used as a factor to determine compliance with a required performance 
standard.
    (b) VSO and VS1 must be determined by flight 
tests, using the procedure and meeting the flight characteristics 
specified in Sec. 23.201.
    (c) Except as provided in paragraph (d) of this section, 
VSO and VS1 at maximum weight must not exceed 61 
knots for--
    (1) Single-engine airplanes; and
    (2) Multiengine airplanes of 6,000 pounds or less maximum weight 
that cannot meet the minimum rate of climb specified in Sec. 23.67(a) 
(1) with the critical engine inoperative.
    (d) All single-engine airplanes, and those multiengine airplanes of 
6,000 pounds or less maximum weight with a VSO of more than 
61 knots that do not meet the requirements of Sec. 23.67(a)(1), must 
comply with Sec. 23.562(d).

[Doc. No. 27807, 61 FR 5184, Feb. 9, 1996]