[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: 14CFR25.121]
[Page 349-350]
TITLE 14--AERONAUTICS AND SPACE
CHAPTER I--FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION
PART 25--AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES--Table of Contents
Subpart B--Flight
Sec. 25.121 Climb: One-engine-inoperative.
(a) Takeoff; landing gear extended. In the critical takeoff
configuration existing along the flight path (between the points at
which the airplane reaches VLOF and at which the landing gear
is fully retracted) and in the configuration used in Sec. 25.111 but
without ground effect, the steady gradient of climb must be positive for
two-engine airplanes, and not less than 0.3 percent for three-engine
airplanes or 0.5 percent for four-engine airplanes, at VLOF
and with--
(1) The critical engine inoperative and the remaining engines at the
power or thrust available when retraction of the landing gear is begun
in accordance
[[Page 350]]
with Sec. 25.111 unless there is a more critical power operating
condition existing later along the flight path but before the point at
which the landing gear is fully retracted; and
(2) The weight equal to the weight existing when retraction of the
landing gear is begun, determined under Sec. 25.111.
(b) Takeoff; landing gear retracted. In the takeoff configuration
existing at the point of the flight path at which the landing gear is
fully retracted, and in the configuration used in Sec. 25.111 but
without ground effect, the steady gradient of climb may not be less than
2.4 percent for two-engine airplanes, 2.7 percent for three-engine
airplanes, and 3.0 percent for four-engine airplanes, at V2
and with--
(1) The critical engine inoperative, the remaining engines at the
takeoff power or thrust available at the time the landing gear is fully
retracted, determined under Sec. 25.111, unless there is a more critical
power operating condition existing later along the flight path but
before the point where the airplane reaches a height of 400 feet above
the takeoff surface; and
(2) The weight equal to the weight existing when the airplane's
landing gear is fully retracted, determined under Sec. 25.111.
(c) Final takeoff. In the en route configuration at the end of the
takeoff path determined in accordance with Sec. 25.111, the steady
gradient of climb may not be less than 1.2 percent for two-engine
airplanes, 1.5 percent for three-engine airplanes and 1.7 percent for
four-engine airplanes, at VFTO and with
(1) The critical engine inoperative and the remaining engines at the
available maximum continuous power or thrust; and
(2) The weight equal to the weight existing at the end of the
takeoff path, determined under Sec. 25.111.
(d) Approach. In a configuration corresponding to the normal all-
engines-operating procedure in which VSR for this
configuration does not exceed 110 percent of the VSR for the
related all-engines-operating landing configuration, the steady gradient
of climb may not be less than 2.1 percent for two-engine airplanes, 2.4
percent for three-engine airplanes, and 2.7 percent for four engine
airplanes, with
(1) The critical engine inoperative, the remaining engines at the
go-around power or thrust setting;
(2) The maximum landing weight;
(3) A climb speed established in connection with normal landing
procedures, but not more than 1.4 VSR; and
(4) Landing gear retracted.
[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as amended by Amdt. 25-84,
60 FR 30749, June 9, 1995; Amdt. 25-108, 67 FR 70826, Nov. 26, 2002]