(where N is the number of engines installed and VSo
is expressed in knots) at an altitude of at least 1,000 feet above the
highest ground or obstruction within 10 miles of each side of the intended
track. However, for the purposes of this paragraph the rate of climb for
airplanes certificated under part 4a of the Civil Air Regulations is 0.026
(b) In place of the requirements of paragraph (a) of this section, a
person may, under an approved procedure, operate a reciprocating engine
powered airplane, at an all-engines-operating altitude that allows the
airplane to continue, after an engine failure, to an alternate airport
where a landing can be made in accordance with §121.187, allowing for
normal consumption of fuel and oil. After the assumed failure, the flight
path must clear the ground and any obstruction within five miles on each
side of the intended track by at least 2,000 feet.
(c) If an approved procedure under paragraph (b) of this section is
used, the certificate holder shall comply with the following:
(1) The rate of climb (as prescribed in the Airplane Flight Manual for
the appropriate weight and altitude) used in calculating the airplane's
flight path shall be diminished by an amount, in feet per minute, equal to
(when N is the number of engines installed and VSo
is expressed in knots) for airplanes certificated under part 25 of this
chapter and by 0.026 Vso2 for airplanes certificated under
part 4a of the Civil Air Regulations.
(2) The all-engines-operating altitude shall be sufficient so that in
the event the critical engine becomes inoperative at any point along the
route, the flight will be able to proceed to a predetermined alternate
airport by use of this procedure. In determining the takeoff weight, the
airplane is assumed to pass over the critical obstruction following engine
failure at a point no closer to the critical obstruction than the nearest
approved radio navigational fix, unless the Administrator approves a
procedure established on a different basis upon finding that adequate
operational safeguards exist.
(3) The airplane must meet the provisions of paragraph (a) of this
section at 1,000 feet above the airport used as an alternate in this
(4) The procedure must include an approved method of accounting for
winds and temperatures that would otherwise adversely affect the flight
(5) In complying with this procedure fuel jettisoning is allowed if the
certificate holder shows that it has an adequate training program, that
proper instructions are given to the flight crew, and all other
precautions are taken to insure a safe procedure.
(6) The certificate holder shall specify in the dispatch or flight
release an alternate airport that meets the requirements of §121.625.
(d) This section does not apply to large nontransport category
airplanes operated under §121.173(c).
[Doc. No. 6258, 29 FR 19198, Dec. 31, 1964; 30 FR 130, Jan. 7,
1965, as amended by Amdt. 121-251, 60 FR 65928, Dec. 20, 1995]