446 

14 CFR Ch. I (1–1–24 Edition) 

§ 135.147 

However, pilot flight training may be 
conducted during the proving tests. 

(d) Validation testing is required to 

determine that a certificate holder is 
capable of conducting operations safely 
and in compliance with applicable reg-
ulatory standards. Validation tests are 
required for the following authoriza-
tions: 

(1) The addition of an aircraft for 

which two pilots are required for oper-
ations under VFR or a turbojet air-
plane, if that aircraft or an aircraft of 
the same make or similar design has 
not been previously proved or validated 
in operations under this part. 

(2) Operations outside U.S. airspace. 
(3) Class II navigation authoriza-

tions. 

(4) Special performance or oper-

ational authorizations. 

(e) Validation tests must be accom-

plished by test methods acceptable to 
the Administrator. Actual flights may 
not be required when an applicant can 
demonstrate competence and compli-
ance with appropriate regulations 
without conducting a flight. 

(f) Proving tests and validation tests 

may be conducted simultaneously 
when appropriate. 

(g) The Administrator may authorize 

deviations from this section if the Ad-
ministrator finds that special cir-
cumstances make full compliance with 
this section unnecessary. 

[Doc. No. FAA–2001–10047, 68 FR 54586, Sept. 
17, 2003] 

§ 135.147 Dual controls required. 

No person may operate an aircraft in 

operations requiring two pilots unless 
it is equipped with functioning dual 
controls. However, if the aircraft type 
certification operating limitations do 
not require two pilots, a throwover 
control wheel may be used in place of 
two control wheels. 

§ 135.149 Equipment requirements: 

General. 

No person may operate an aircraft 

unless it is equipped with— 

(a) A sensitive altimeter that is ad-

justable for barometric pressure; 

(b) Heating or deicing equipment for 

each carburetor or, for a pressure car-
buretor, an alternate air source; 

(c) For turbojet airplanes, in addition 

to two gyroscopic bank-and-pitch indi-
cators (artificial horizons) for use at 
the pilot stations, a third indicator 
that is installed in accordance with the 
instrument requirements prescribed in 
§ 121.305(j) of this chapter. 

(d) [Reserved] 
(e) For turbine powered aircraft, any 

other equipment as the Administrator 
may require. 

[Doc. No. 16097, 43 FR 46783, Oct. 10, 1978, as 
amended at Amdt. 135–1, 44 FR 26737, May 7, 
1979; Amdt. 135–34, 54 FR 43926, Oct. 27, 1989; 
Amdt. 135–38, 55 FR 43310, Oct. 26, 1990] 

§ 135.150 Public address and crew-

member interphone systems. 

No person may operate an aircraft 

having a passenger seating configura-
tion, excluding any pilot seat, of more 
than 19 unless it is equipped with— 

(a) A public address system which— 
(1) Is capable of operation inde-

pendent of the crewmember interphone 
system required by paragraph (b) of 
this section, except for handsets, head-
sets, microphones, selector switches, 
and signaling devices; 

(2) Is approved in accordance with 

§ 21.305 of this chapter; 

(3) Is accessible for immediate use 

from each of two flight crewmember 
stations in the pilot compartment; 

(4) For each required floor-level pas-

senger emergency exit which has an ad-
jacent flight attendant seat, has a 
microphone which is readily accessible 
to the seated flight attendant, except 
that one microphone may serve more 
than one exit, provided the proximity 
of the exits allows unassisted verbal 
communication between seated flight 
attendants; 

(5) Is capable of operation within 10 

seconds by a flight attendant at each of 
those stations in the passenger com-
partment from which its use is acces-
sible; 

(6) Is audible at all passenger seats, 

lavatories, and flight attendant seats 
and work stations; and 

(7) For transport category airplanes 

manufactured on or after November 27, 
1990, meets the requirements of § 25.1423 
of this chapter. 

(b) A crewmember interphone system 

which—