[Code of Federal Regulations]

[Title 14, Volume 1]

[Revised as of January 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 14CFR25.111]



[Page 353-354]

 

                     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. 25.111  Takeoff path.



    (a) The takeoff path extends from a standing start to a point in the 

takeoff at which the airplane is 1,500 feet above the takeoff surface, 

or at which the transition from the takeoff to the en route 

configuration is completed and VFTO is reached, whichever 

point is higher. In addition--

    (1) The takeoff path must be based on the procedures prescribed in 

Sec. 25.101(f);



[[Page 354]]



    (2) The airplane must be accelerated on the ground to VEF, at which 

point the critical engine must be made inoperative and remain 

inoperative for the rest of the takeoff; and

    (3) After reaching VEF, the airplane must be accelerated to 

V2.

    (b) During the acceleration to speed V2, the nose gear 

may be raised off the ground at a speed not less than VR. However, 

landing gear retraction may not be begun until the airplane is airborne.

    (c) During the takeoff path determination in accordance with 

paragraphs (a) and (b) of this section--

    (1) The slope of the airborne part of the takeoff path must be 

positive at each point;

    (2) The airplane must reach V2 before it is 35 feet above the 

takeoff surface and must continue at a speed as close as practical to, 

but not less than V2, until it is 400 feet above the takeoff surface;

    (3) At each point along the takeoff path, starting at the point at 

which the airplane reaches 400 feet above the takeoff surface, the 

available gradient of climb may not be less than--

    (i) 1.2 percent for two-engine airplanes;

    (ii) 1.5 percent for three-engine airplanes; and

    (iii) 1.7 percent for four-engine airplanes; and

    (4) Except for gear retraction and automatic propeller feathering, 

the airplane configuration may not be changed, and no change in power or 

thrust that requires action by the pilot may be made, until the airplane 

is 400 feet above the takeoff surface.

    (d) The takeoff path must be determined by a continuous demonstrated 

takeoff or by synthesis from segments. If the takeoff path is determined 

by the segmental method--

    (1) The segments must be clearly defined and must be related to the 

distinct changes in the configuration, power or thrust, and speed;

    (2) The weight of the airplane, the configuration, and the power or 

thrust must be constant throughout each segment and must correspond to 

the most critical condition prevailing in the segment;

    (3) The flight path must be based on the airplane's performance 

without ground effect; and

    (4) The takeoff path data must be checked by continuous demonstrated 

takeoffs up to the point at which the airplane is out of ground effect 

and its speed is stabilized, to ensure that the path is conservative 

relative to the continous path.



The airplane is considered to be out of the ground effect when it 

reaches a height equal to its wing span.

    (e) For airplanes equipped with standby power rocket engines, the 

takeoff path may be determined in accordance with section II of appendix 

E.



[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as amended by Amdt. 25-6, 30 

FR 8468, July 2, 1965; Amdt. 25-42, 43 FR 2321, Jan. 16, 1978; Amdt. 25-

54, 45 FR 60172, Sept. 11, 1980; Amdt. 25-72, 55 FR 29774, July 20, 

1990; Amdt. 25-94, 63 FR 8848, Feb. 23, 1998; Amdt. 25-108, 67 FR 70826, 

Nov. 26, 2002; Amdt. 25-115, 69 FR 40527, July 2, 2004]