101 

Federal Aviation Administration, DOT 

§ 121.191 

§ 121.189 Airplanes: Turbine engine 

powered: Takeoff limitations. 

(a) No person operating a turbine en-

gine powered airplane may take off 
that airplane at a weight greater than 
that listed in the Airplane Flight Man-
ual for the elevation of the airport and 
for the ambient temperature existing 
at takeoff. 

(b) No person operating a turbine en-

gine powered airplane certificated after 
August 26, 1957, but before August 30, 
1959 (SR422, 422A), may take off that 
airplane at a weight greater than that 
listed in the Airplane Flight Manual 
for the minimum distances required for 
takeoff. In the case of an airplane cer-
tificated after September 30, 1958 
(SR422A, 422B), the takeoff distance 
may include a clearway distance but 
the clearway distance included may 
not be greater than 

1

⁄

2

of the takeoff 

run. 

(c) No person operating a turbine en-

gine powered airplane certificated after 
August 29, 1959 (SR422B), may take off 
that airplane at a weight greater than 
that listed in the Airplane Flight Man-
ual at which compliance with the fol-
lowing may be shown: 

(1) The accelerate-stop distance must 

not exceed the length of the runway 
plus the length of any stopway. 

(2) The takeoff distance must not ex-

ceed the length of the runway plus the 
length of any clearway except that the 
length of any clearway included must 
not be greater than one-half the length 
of the runway. 

(3) The takeoff run must not be 

greater than the length of the runway. 

(d) No person operating a turbine en-

gine powered airplane may take off 
that airplane at a weight greater than 
that listed in the Airplane Flight Man-
ual— 

(1) In the case of an airplane certifi-

cated after August 26, 1957, but before 
October 1, 1958 (SR422), that allows a 
takeoff path that clears all obstacles 
either by at least (35 + 0.01D) feet 
vertically (D is the distance along the 
intended flight path from the end of 
the runway in feet), or by at least 200 
feet horizontally within the airport 
boundaries and by at least 300 feet 
horizontally after passing the bound-
aries; or 

(2) In the case of an airplane certifi-

cated after September 30, 1958 (SR 
422A, 422B), that allows a net takeoff 
flight path that clears all obstacles ei-
ther by a height of at least 35 feet 
vertically, or by at least 200 feet hori-
zontally within the airport boundaries 
and by at least 300 feet horizontally 
after passing the boundaries. 

(e) In determining maximum 

weights, minimum distances, and flight 
paths under paragraphs (a) through (d) 
of this section, correction must be 
made for the runway to be used, the 
elevation of the airport, the effective 
runway gradient, the ambient tempera-
ture and wind component at the time 
of takeoff, and, if operating limitations 
exist for the minimum distances re-
quired for takeoff from wet runways, 
the runway surface condition (dry or 
wet). Wet runway distances associated 
with grooved or porous friction course 
runways, if provided in the Airplane 
Flight Manual, may be used only for 
runways that are grooved or treated 
with a porous friction course (PFC) 
overlay, and that the operator deter-
mines are designed, constructed, and 
maintained in a manner acceptable to 
the Administrator. 

(f) For the purposes of this section, it 

is assumed that the airplane is not 
banked before reaching a height of 50 
feet, as shown by the takeoff path or 
net takeoff flight path data (as appro-
priate) in the Airplane Flight Manual, 
and thereafter that the maximum bank 
is not more than 15 degrees. 

(g) For the purposes of this section 

the terms, 

takeoff distance, takeoff run, 

net takeoff flight path 

and 

takeoff path 

have the same meanings as set forth in 
the rules under which the airplane was 
certificated. 

[Doc. No. 6258, 29 FR 19198, Dec. 31, 1964, as 
amended by Amdt. 121–268, 63 FR 8321, Feb. 
18, 1998] 

§ 121.191 Airplanes: Turbine engine 

powered: En route limitations: One 

engine inoperative. 

(a) No person operating a turbine en-

gine powered airplane may take off 
that airplane at a weight, allowing for 
normal consumption of fuel and oil, 
that is greater than that which (under 
the approved, one engine inoperative, 
en route net flight path data in the 

102 

14 CFR Ch. I (1–1–24 Edition) 

§ 121.193 

Airplane Flight Manual for that air-
plane) will allow compliance with para-
graph (a) (1) or (2) of this section, based 
on the ambient temperatures expected 
en route: 

(1) There is a positive slope at an al-

titude of at least 1,000 feet above all 
terrain and obstructions within five 
statute miles on each side of the in-
tended track, and, in addition, if that 
airplane was certificated after August 
29, 1959 (SR 422B) there is a positive 
slope at 1,500 feet above the airport 
where the airplane is assumed to land 
after an engine fails. 

(2) The net flight path allows the air-

plane to continue flight from the cruis-
ing altitude to an airport where a land-
ing can be made under § 121.197, clear-
ing all terrain and obstructions within 
five statute miles of the intended track 
by at least 2,000 feet vertically and 
with a positive slope at 1,000 feet above 
the airport where the airplane lands 
after an engine fails, or, if that air-
plane was certificated after September 
30, 1958 (SR 422A, 422B), with a positive 
slope at 1,500 feet above the airport 
where the airplane lands after an en-
gine fails. 

(b) For the purposes of paragraph 

(a)(2) of this section, it is assumed 
that— 

(1) The engine fails at the most crit-

ical point en route; 

(2) The airplane passes over the crit-

ical obstruction, after engine failure at 
a point that is no closer to the obstruc-
tion than the nearest approved radio 
navigation fix, unless the Adminis-
trator authorizes a different procedure 
based on adequate operational safe-
guards; 

(3) An approved method is used to 

allow for adverse winds: 

(4) Fuel jettisoning will be allowed if 

the certificate holder shows that the 
crew is properly instructed, that the 
training program is adequate, and that 
all other precautions are taken to in-
sure a safe procedure; 

(5) The alternate airport is specified 

in the dispatch or flight release and 
meets the prescribed weather mini-
mums; and 

(6) The consumption of fuel and oil 

after engine failure is the same as the 
consumption that is allowed for in the 

approved net flight path data in the 
Airplane Flight Manual. 

[Doc. No. 6258, 29 FR 19198, Dec. 31, 1964; 30 
FR 130, Jan. 7, 1965, as amended by Amdt. 
121–143, 43 FR 22641, May 25, 1978] 

§ 121.193 Airplanes: Turbine engine 

powered: En route limitations: Two 

engines inoperative. 

(a) 

Airplanes certificated after August 

26, 1957, but before October 1, 1958 

(SR 

422). No person may operate a turbine 
engine powered airplane along an in-
tended route unless he complies with 
either of the following: 

(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 the requirements of § 121.197. 

(2) Its weight, according to the two- 

engine-inoperative, en route, net flight 
path data in the Airplane Flight Man-
ual, allows the airplane to fly from the 
point where the two engines are as-
sumed to fail simultaneously to an air-
port that meets the requirements of 
§ 121.197, with a net flight path (consid-
ering the ambient temperature antici-
pated along the track) having a posi-
tive slope at an altitude of at least 
1,000 feet above all terrain and obstruc-
tions within five miles on each side of 
the intended track, or at an altitude of 
5,000 feet, whichever is higher. 

For the purposes of paragraph (a)(2) of 
this section, it is assumed that the two 
engines fail at the most critical point 
en route, that if fuel jettisoning is pro-
vided, the airplane’s weight at the 
point where the engines fail includes 
enough fuel to continue to the airport 
and to arrive at an altitude of at least 
1,000 feet directly over the airport, and 
that the fuel and oil consumption after 
engine failure is the same as the con-
sumption allowed for in the net flight 
path data in the Airplane Flight Man-
ual. 

(b) 

Aircraft certificated after September 

30, 1958, but before August 30, 1959 

(SR 

422A). No person may operate a turbine 
engine powered airplane along an in-
tended route unless he complies with 
either of the following: 

(1) There is no place along the in-

tended track that is more than 90 min-
utes (with all engines operating at