339
Federal Aviation Administration, DOT
§ 25.1305
(4) A gyroscopic rate-of-turn indi-
cator combined with an integral slip-
skid indicator (turn-and-bank indi-
cator) except that only a slip-skid indi-
cator is required on large airplanes
with a third attitude instrument sys-
tem useable through flight attitudes of
360
°
of pitch and roll and installed in
accordance with § 121.305(k) of this
title.
(5) A bank and pitch indicator (gyro-
scopically stabilized).
(6) A direction indicator (gyroscop-
ically stabilized, magnetic or non-
magnetic).
(c) The following flight and naviga-
tion instruments are required as pre-
scribed in this paragraph:
(1) A speed warning device is required
for turbine engine powered airplanes
and for airplanes with V
MO
/M
MO
greater
than 0.8 V
DF
/M
DF
or 0.8 V
D
/M
D
. The
speed warning device must give effec-
tive aural warning (differing distinc-
tively from aural warnings used for
other purposes) to the pilots, whenever
the speed exceeds V
MO
plus 6 knots or
M
MO
+ 0.01. The upper limit of the pro-
duction tolerance for the warning de-
vice may not exceed the prescribed
warning speed.
(2) A machmeter is required at each
pilot station for airplanes with com-
pressibility limitations not otherwise
indicated to the pilot by the airspeed
indicating system required under para-
graph (b)(1) of this section.
[Amdt. 25–23, 35 FR 5678, Apr. 8, 1970, as
amended by Amdt. 25–24, 35 FR 7108, May 6,
1970; Amdt. 25–38, 41 FR 55467, Dec. 20, 1976;
Amdt. 25–90, 62 FR 13253, Mar. 19, 1997]
§ 25.1305
Powerplant instruments.
The following are required power-
plant instruments:
(a)
For all airplanes. (1) A fuel pres-
sure warning means for each engine, or
a master warning means for all engines
with provision for isolating the indi-
vidual warning means from the master
warning means.
(2) A fuel quantity indicator for each
fuel tank.
(3) An oil quantity indicator for each
oil tank.
(4) An oil pressure indicator for each
independent pressure oil system of
each engine.
(5) An oil pressure warning means for
each engine, or a master warning
means for all engines with provision
for isolating the individual warning
means from the master warning means.
(6) An oil temperature indicator for
each engine.
(7) Fire-warning devices that provide
visual and audible warning.
(8) An augmentation liquid quantity
indicator (appropriate for the manner
in which the liquid is to be used in op-
eration) for each tank.
(b)
For reciprocating engine-powered
airplanes. In addition to the powerplant
instruments required by paragraph (a)
of this section, the following power-
plant instruments are required:
(1) A carburetor air temperature indi-
cator for each engine.
(2) A cylinder head temperature indi-
cator for each air-cooled engine.
(3) A manifold pressure indicator for
each engine.
(4) A fuel pressure indicator (to indi-
cate the pressure at which the fuel is
supplied) for each engine.
(5) A fuel flowmeter, or fuel mixture
indicator, for each engine without an
automatic altitude mixture control.
(6) A tachometer for each engine.
(7) A device that indicates, to the
flight crew (during flight), any change
in the power output, for each engine
with—
(i) An automatic propeller feathering
system, whose operation is initiated by
a power output measuring system; or
(ii) A total engine piston displace-
ment of 2,000 cubic inches or more.
(8) A means to indicate to the pilot
when the propeller is in reverse pitch,
for each reversing propeller.
(c)
For turbine engine-powered air-
planes. In addition to the powerplant
instruments required by paragraph (a)
of this section, the following power-
plant instruments are required:
(1) A gas temperature indicator for
each engine.
(2) A fuel flowmeter indicator for
each engine.
(3) A tachometer (to indicate the
speed of the rotors with established
limiting speeds) for each engine.
(4) A means to indicate, to the flight
crew, the operation of each engine
starter that can be operated continu-
ously but that is neither designed for
VerDate Sep<11>2014
09:06 Jun 28, 2024
Jkt 262046
PO 00000
Frm 00349
Fmt 8010
Sfmt 8010
Y:\SGML\262046.XXX
262046
jspears on DSK121TN23PROD with CFR
340
14 CFR Ch. I (1–1–24 Edition)
§ 25.1307
continuous operation nor designed to
prevent hazard if it failed.
(5) An indicator to indicate the func-
tioning of the powerplant ice protec-
tion system for each engine.
(6) An indicator for the fuel strainer
or filter required by § 25.997 to indicate
the occurrence of contamination of the
strainer or filter before it reaches the
capacity established in accordance
with § 25.997(d).
(7) A warning means for the oil
strainer or filter required by § 25.1019, if
it has no bypass, to warn the pilot of
the occurrence of contamination of the
strainer or filter screen before it
reaches the capacity established in ac-
cordance with § 25.1019(a)(2).
(8) An indicator to indicate the prop-
er functioning of any heater used to
prevent ice clogging of fuel system
components.
(d)
For turbojet engine powered air-
planes. In addition to the powerplant
instruments required by paragraphs (a)
and (c) of this section, the following
powerplant instruments are required:
(1) An indicator to indicate thrust, or
a parameter that is directly related to
thrust, to the pilot. The indication
must be based on the direct measure-
ment of thrust or of parameters that
are directly related to thrust. The indi-
cator must indicate a change in thrust
resulting from any engine malfunction,
damage, or deterioration.
(2) A position indicating means to in-
dicate to the flightcrew when the
thrust reversing device—
(i) Is not in the selected position, and
(ii) Is in the reverse thrust position,
for each engine using a thrust revers-
ing device.
(3) An indicator to indicate rotor sys-
tem unbalance.
(e)
For turbopropeller-powered air-
planes. In addition to the powerplant
instruments required by paragraphs (a)
and (c) of this section, the following
powerplant instruments are required:
(1) A torque indicator for each en-
gine.
(2) Position indicating means to indi-
cate to the flight crew when the pro-
peller blade angle is below the flight
low pitch position, for each propeller.
(f) For airplanes equipped with fluid
systems (other than fuel) for thrust or
power augmentation, an approved
means must be provided to indicate the
proper functioning of that system to
the flight crew.
[Amdt. 25–23, 35 FR 5678, Apr. 8, 1970, as
amended by Amdt. 25–35, 39 FR 1831, Jan. 15,
1974; Amdt. 25–36, 39 FR 35461, Oct. 1, 1974;
Amdt. 25–38, 41 FR 55467, Dec. 20, 1976; Amdt.
25–54, 45 FR 60173, Sept. 11, 1980; Amdt. 25–72,
55 FR 29785, July 20, 1990; Amdt. 25–115, 69 FR
40527, July 2, 2004]
§ 25.1307
Miscellaneous equipment.
The following is required miscella-
neous equipment:
(a) [Reserved]
(b) Two or more independent sources
of electrical energy.
(c) Electrical protective devices, as
prescribed in this part.
(d) Two systems for two-way radio
communications, with controls for
each accessible from each pilot station,
designed and installed so that failure of
one system will not preclude operation
of the other system. The use of a com-
mon antenna system is acceptable if
adequate reliability is shown.
(e) Two systems for radio navigation,
with controls for each accessible from
each pilot station, designed and in-
stalled so that failure of one system
will not preclude operation of the other
system. The use of a common antenna
system is acceptable if adequate reli-
ability is shown.
[Amdt. 25–23, 35 FR 5678, Apr. 8, 1970, as
amended by Amdt. 25–46, 43 FR 50598, Oct. 30,
1978; Amdt. 25–54, 45 FR 60173, Sept. 11, 1980;
Amdt. 25–72, 55 FR 29785, July 20, 1990]
§ 25.1309
Equipment, systems, and in-
stallations.
(a) The equipment, systems, and in-
stallations whose functioning is re-
quired by this subchapter, must be de-
signed to ensure that they perform
their intended functions under any
foreseeable operating condition.
(b) The airplane systems and associ-
ated components, considered sepa-
rately and in relation to other systems,
must be designed so that—
(1) The occurrence of any failure con-
dition which would prevent the contin-
ued safe flight and landing of the air-
plane is extremely improbable, and
(2) The occurrence of any other fail-
ure conditions which would reduce the
capability of the airplane or the ability
VerDate Sep<11>2014
09:06 Jun 28, 2024
Jkt 262046
PO 00000
Frm 00350
Fmt 8010
Sfmt 8010
Y:\SGML\262046.XXX
262046
jspears on DSK121TN23PROD with CFR