title-14-part-27-sec27-1309

547

Federal Aviation Administration, DOT

§ 27.1309

(1) Provide a warning to the

flightcrew when approximately 10 min-
utes of usable fuel remains in the tank;
and

(2) Be independent of the normal fuel

quantity indicating system.

(m) Means to indicate to the

flightcrew the failure of any fuel pump
installed to show compliance with
§ 27.955.

(n) A means to indicate the gas tem-

perature for each turbine engine.

(o) A means to enable the pilot to de-

termine the torque of each turbine en-
gine, if a torque limitation is estab-
lished for that engine under § 27.1521(e).

(p) For each turbine engine, an indi-

cator to indicate the functioning of the
powerplant ice protection system.

(q) An indicator for the fuel filter re-

quired by § 27.997 to indicate the occur-
rence of contamination of the filter at
the degree established by the applicant
in compliance with § 27.955.

(r) For each turbine engine, a warn-

ing means for the oil strainer or filter
required by § 27.1019, if it has no bypass,
to warn the pilot of the occurrence of
contamination of the strainer or filter
before it reaches the capacity estab-
lished in accordance with § 27.1019(a)(2).

(s) An indicator to indicate the func-

tioning of any selectable or control-
lable heater used to prevent ice clog-
ging of fuel system components.

(t) For rotorcraft for which a 30-sec-

ond/2-minute OEI power rating is re-
quested, a means must be provided to
alert the pilot when the engine is at
the 30-second and the 2-minute OEI
power levels, when the event begins,
and when the time interval expires.

(u) For each turbine engine utilizing

30-second/2-minute OEI power, a device
or system must be provided for use by
ground personnel which—

(1) Automatically records each usage

and duration of power at the 30-second
and 2-minute OEI levels;

(2) Permits retrieval of the recorded

data;

(3) Can be reset only by ground main-

tenance personnel; and

(4) Has a means to verify proper oper-

ation of the system or device.

(v) Warning or caution devices to sig-

nal to the flight crew when ferromag-

netic particles are detected by the chip
detector required by § 27.1337(e).

[Doc. No. 5074, 29 FR 15695, Nov. 24, 1964, as
amended by Amdt. 27–9, 39 FR 35462, Oct. 1,
1974; Amdt. 27–23, 53 FR 34214, Sept. 2, 1988;
Amdt. 27–29, 59 FR 47767, Sept. 16, 1994; Amdt.
27–37, 64 FR 45095, Aug. 18, 1999; 64 FR 47563,
Aug. 31, 1999; Amdt. 27–51, 88 FR 8737, Feb. 10,
2023]

§ 27.1307

Miscellaneous equipment.

The following is the required mis-

cellaneous equipment:

(a) An approved seat for each occu-

pant.

(b) An approved safety belt for each

occupant.

energy, where electrical energy is nec-
essary for operation of the rotorcraft.

(e) Electrical protective devices.

§ 27.1309

Equipment, systems, and in-

stallations.

The equipment, systems, and instal-

lations whose functioning is required
by this subchapter must be designed
and installed to ensure that they per-
form their intended functions under
any foreseeable operating condition.
For any item of equipment or system
whose failure has not been specifically
addressed by another requirement in
this chapter, the following require-
ments also apply:

(a) The design of each item of equip-

ment, system, and installation must be
analyzed separately and in relation to
other rotorcraft systems and installa-
tions to determine and identify any
failure that would affect the capability
of the rotorcraft or the ability of the
crew to perform their duties in all op-
erating conditions.

(b) Each item of equipment, system,

and installation must be designed and
installed so that:

(1) The occurrence of any cata-

strophic failure condition is extremely
improbable;

(2) The occurrence of any major fail-

ure condition is no more than improb-
able; and

(3) For the occurrence of any other

failure condition between major and
catastrophic, the probability of the
failure condition must be inversely
proportional to its consequences.

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548

14 CFR Ch. I (1–1–24 Edition)

§ 27.1316

event of a failure must be provided
when an unsafe system operating con-
dition exists and to enable them to
take corrective action. Systems, con-
trols, and associated monitoring and
crew alerting means must be designed
to minimize crew errors that could cre-
ate additional hazards.

(d) Compliance with the require-

ments of this section must be shown by
analysis and, where necessary, by
ground, flight, or simulator tests. The
analysis must account for:

(1) Possible modes of failure, includ-

ing malfunctions and misleading data
and input from external sources;

(2) The effect of multiple failures and

latent failures;

(3) The resulting effects on the rotor-

craft and occupants, considering the
stage of flight and operating condi-
tions; and

(4) The crew alerting cues and the

corrective action required.

[Amdt. 27–51, 88 FR 8737, Feb. 10, 2023]

§ 27.1316

Electrical and electronic sys-

tem lightning protection.

(a) Each electrical and electronic

system that performs a function, for
which failure would prevent the contin-
ued safe flight and landing of the rotor-
craft, must be designed and installed so
that—

(1) The function is not adversely af-

fected during and after the time the
rotorcraft is exposed to lightning; and

(2) The system automatically recov-

ers normal operation of that function
in a timely manner after the rotorcraft
is exposed to lightning.

(b) For rotorcraft approved for in-

strument flight rules operation, each
electrical and electronic system that
performs a function, for which failure
would reduce the capability of the
rotorcraft or the ability of the
flightcrew to respond to an adverse op-
erating condition, must be designed
and installed so that the function re-
covers normal operation in a timely
manner after the rotorcraft is exposed
to lightning.

[Doc. No. FAA–2010–0224, Amdt. 27–46, 76 FR
33135, June 8, 2011]

§ 27.1317

High-intensity Radiated

Fields (HIRF) Protection.

(a) Except as provided in paragraph

(d) of this section, each electrical and
electronic system that performs a func-
tion whose failure would prevent the
continued safe flight and landing of the
rotorcraft must be designed and in-
stalled so that—

(1) The function is not adversely af-

fected during and after the time the
rotorcraft is exposed to HIRF environ-
ment I, as described in appendix D to
this part;

(2) The system automatically recov-

ers normal operation of that function,
in a timely manner, after the rotor-
craft is exposed to HIRF environment
I, as described in appendix D to this
part, unless this conflicts with other
operational or functional requirements
of that system;

(3) The system is not adversely af-

fected during and after the time the
rotorcraft is exposed to HIRF environ-
ment II, as described in appendix D to
this part; and

(4) Each function required during op-

eration under visual flight rules is not
adversely affected during and after the
time the rotorcraft is exposed to HIRF
environment III, as described in appen-
dix D to this part.

(b) Each electrical and electronic

system that performs a function whose
failure would significantly reduce the
capability of the rotorcraft or the abil-
ity of the flightcrew to respond to an
adverse operating condition must be
designed and installed so the system is
not adversely affected when the equip-
ment providing these functions is ex-
posed to equipment HIRF test level 1
or 2, as described in appendix D to this
part.

tem that performs a function whose
failure would reduce the capability of
the rotorcraft or the ability of the
flightcrew to respond to an adverse op-
erating condition, must be designed
and installed so the system is not ad-
versely affected when the equipment
providing these functions is exposed to
equipment HIRF test level 3, as de-
scribed in appendix D to this part.

(d) Before December 1, 2012, an elec-

trical or electronic system that per-
forms a function whose failure would