501
Federal Aviation Administration, DOT
§ 135.375
upon finding that adequate operational
safeguards exist.
(3) The airplane must meet the provi-
sions of paragraph (a) of this section at
1,000 feet above the airport used as an
alternate in this procedure.
(4) The procedure must include an ap-
proved method of accounting for winds
and temperatures that would otherwise
adversely affect the flight path.
(5) In complying with this procedure,
fuel jettisoning is allowed if the certifi-
cate holder shows that it has an ade-
quate training program, that proper in-
structions are given to the flight crew,
and all other precautions are taken to
ensure a safe procedure.
(6) The certificate holder and the
pilot in command shall jointly elect an
alternate airport for which the appro-
priate weather reports or forecasts, or
any combination of them, indicate that
weather conditions will be at or above
the alternate weather minimum speci-
fied in the certificate holder’s oper-
ations specifications for that airport
when the flight arrives.
[Doc. No. 16097, 43 FR 46783, Oct. 10, 1978, as
amended by Amdt. 135–110, 72 FR 31685, June
7, 2007]
§ 135.373 Part 25 transport category
airplanes with four or more en-
gines: Reciprocating engine pow-
ered: En route limitations: Two en-
gines inoperative.
(a) No person may operate an air-
plane certificated under part 25 and
having four or more engines unless—
(1) There is no place along the in-
tended track that is more than 90 min-
utes (with all engines operating at
cruising power) from an airport that
meets § 135.377; or
(2) It is operated at a weight allowing
the airplane, with the two critical en-
gines inoperative, to climb at 0.013 Vs
o
2
feet per minute (that is, the number of
feet per minute obtained by multi-
plying the number of knots squared by
0.013) at an altitude of 1,000 feet above
the highest ground or obstruction
within 10 miles on each side of the in-
tended track, or at an altitude of 5,000
feet, whichever is higher.
(b) For the purposes of paragraph
(a)(2) of this section, it is assumed
that—
(1) The two engines fail at the point
that is most critical with respect to
the takeoff weight;
(2) Consumption of fuel and oil is nor-
mal with all engines operating up to
the point where the two engines fail
with two engines operating beyond
that point;
(3) Where the engines are assumed to
fail at an altitude above the prescribed
minimum altitude, compliance with
the prescribed rate of climb at the pre-
scribed minimum altitude need not be
shown during the descent from the
cruising altitude to the prescribed min-
imum altitude, if those requirements
can be met once the prescribed min-
imum altitude is reached, and assum-
ing descent to be along a net flight
path and the rate of descent to be 0.013
Vs
o
2 greater than the rate in the ap-
proved performance data; and
(4) If fuel jettisoning is provided, the
airplane’s weight at the point where
the two engines fail is considered to be
not less than that which would include
enough fuel to proceed to an airport
meeting § 135.377 and to arrive at an al-
titude of at least 1,000 feet directly
over that airport.
§ 135.375 Large transport category air-
planes: Reciprocating engine pow-
ered: Landing limitations: Destina-
tion airports.
(a) Except as provided in paragraph
(b) of this section, no person operating
a reciprocating engine powered large
transport category airplane may take
off that airplane, unless its weight on
arrival, allowing for normal consump-
tion of fuel and oil in flight, would
allow a full stop landing at the in-
tended destination within 60 percent of
the effective length of each runway de-
scribed below from a point 50 feet di-
rectly above the intersection of the ob-
struction clearance plane and the run-
way. For the purposes of determining
the allowable landing weight at the
destination airport the following is as-
sumed:
(1) The airplane is landed on the most
favorable runway and in the most fa-
vorable direction in still air.
(2) The airplane is landed on the most
suitable runway considering the prob-
able wind velocity and direction (fore-
cast for the expected time of arrival),
