94 

14 CFR Ch. I (1–1–24 Edition) 

§ 121.155 

§ 121.155 [Reserved] 

§ 121.157 Aircraft certification and 

equipment requirements. 

(a) 

Airplanes certificated before July 1, 

1942. 

No certificate holder may operate 

an airplane that was type certificated 
before July 1, 1942, unless— 

(1) That airplane meets the require-

ments of § 121.173(c), or 

(2) That airplane and all other air-

planes of the same or related type oper-
ated by that certificate holder meet 
the performance requirements of sec-
tions 4a.737–T through 4a.750–T of the 
Civil Air Regulations as in effect on 
January 31, 1965; or §§ 25.45 through 
25.75 and § 121.173(a), (b), (d), and (e) of 
this title. 

(b) 

Airplanes certificated after June 30, 

1942. 

Except as provided in paragraphs 

(c), (d), (e), and (f) of this section, no 
certificate holder may operate an air-
plane that was type certificated after 
June 30, 1942, unless it is certificated as 
a transport category airplane and 
meets the requirements of § 121.173(a), 
(b), (d), and (e). 

(c) 

C–46 type airplanes: passenger-car-

rying operations. 

No certificate holder 

may operate a C–46 airplane in pas-
senger-carrying operations unless that 
airplane is operated in accordance with 
the operating limitations for transport 
category airplanes and meets the re-
quirements of paragraph (b) of this sec-
tion or meets the requirements of part 
4b, as in effect July 20, 1950, and the re-
quirements of § 121.173 (a), (b), (d) and 
(e), except that— 

(1) The requirements of sections 4b.0 

through 4b.19 as in effect May 18, 1954, 
must be complied with; 

(2) The birdproof windshield require-

ments of section 4b.352 need not be 
complied with; 

(3) The provisions of sections 4b.480 

through 4b.490 (except sections 
4b.484(a)(1) and 4b.487(e)), as in effect 
May 16, 1953, must be complied with; 
and 

(4) The provisions of paragraph 

4b.484(a)(1), as in effect July 20, 1950, 
must be complied with. 

In determining the takeoff path in ac-
cordance with section 4b.116 and the 
one-engine inoperative climb in accord-
ance with section 4b.120 (a) and (b), the 
propeller of the inoperative engine may 

be assumed to be feathered if the air-
plane is equipped with either an ap-
proved means for automatically indi-
cating when the particular engine has 
failed or an approved means for auto-
matically feathering the propeller of 
the inoperative engine. The Adminis-
trator may authorize deviations from 
compliance with the requirements of 
sections 4b.130 through 4b.190 and sub-
parts C, D, E, and F of part 4b (as des-
ignated in this paragraph) if he finds 
that (considering the effect of design 
changes) compliance is extremely dif-
ficult to accomplish and that service 
experience with the C–46 airplane justi-
fies the deviation. 

(d) 

C–46 type airplanes: cargo oper-

ations. 

No certificate holder may use a 

nontransport category C–46 type air-
plane in cargo operations unless— 

(1) It is certificated at a maximum 

gross weight that is not greater than 
48,000 pounds; 

(2) It meets the requirements of 

§§ 121.199 through 121.205 using the per-
formance data in appendix C to this 
part; 

(3) Before each flight, each engine 

contains at least 25 gallons of oil; and 

(4) After December 31, 1964— 
(i) It is powered by a type and model 

engine as set forth in appendix C of 
this part, when certificated at a max-
imum gross takeoff weight greater 
than 45,000 pounds; and 

(ii) It complies with the special air-

worthiness requirement set forth in 
§§ 121.213 through 121.287 of this part or 
in appendix C of this part. 

(e) 

Commuter category airplanes. 

Ex-

cept as provided in paragraph (f) of this 
section, no certificate holder may oper-
ate under this part a nontransport cat-
egory airplane type certificated after 
December 31, 1964, and before March 30, 
1995, unless it meets the applicable re-
quirements of § 121.173 (a), (b), (d), and 
(e), and was type certificated in the 
commuter category. 

(f) 

Other nontransport category air-

planes. 

No certificate holder may oper-

ate under this part a nontransport cat-
egory airplane type certificated after 
December 31, 1964, unless it meets the 
applicable requirements of § 121.173 (a), 
(b), (d), and (e), was manufactured be-
fore March 20, 1997, and meets one of 
the following: