title-14-part-27-sec27-865

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14 CFR Ch. I (1–1–24 Edition)

§ 27.861

Fire protection of structure,

controls, and other parts.

Each part of the structure, controls,

rotor mechanism, and other parts es-
sential to a controlled landing that
would be affected by powerplant fires
must be fireproof or protected so they
can perform their essential functions
for at least 5 minutes under any fore-
seeable powerplant fire conditions.

[Amdt. 27–26, 55 FR 8001, Mar. 6, 1990]

§ 27.863

Flammable fluid fire protec-

tion.

(a) In each area where flammable

fluids or vapors might escape by leak-
age of a fluid system, there must be
means to minimize the probability of
ignition of the fluids and vapors, and
the resultant hazards if ignition does
occur.

(b) Compliance with paragraph (a) of

this section must be shown by analysis
or tests, and the following factors must
be considered:

(1) Possible sources and paths of fluid

leakage, and means of detecting leak-
age.

(2) Flammability characteristics of

fluids, including effects of any combus-
tible or absorbing materials.

(3) Possible ignition sources, includ-

ing electrical faults, overheating of
equipment, and malfunctioning of pro-
tective devices.

(4) Means available for controlling or

extinguishing a fire, such as stopping
flow of fluids, shutting down equip-
ment, fireproof containment, or use of
extinguishing agents.

(5) Ability of rotorcraft components

that are critical to safety of flight to
withstand fire and heat.

quired to prevent or counteract a fluid
fire (e.g. equipment shutdown or actu-
ation of a fire extinguisher) quick act-
ing means must be provided to alert
the crew.

(d) Each area where flammable fluids

or vapors might escape by leakage of a
fluid system must be identified and de-
fined.

(Secs. 313(a), 601, 603, 604, Federal Aviation
Act of 1958 (49 U.S.C. 1354(a), 1421, 1423, 1424),
sec. 6(c), Dept. of Transportation Act (49
U.S.C. 1655(c)))

[Amdt. 27–16, 43 FR 50599, Oct. 30, 1978]

XTERNAL

OADS

§ 27.865

External loads.

(a) It must be shown by analysis,

test, or both, that the rotorcraft exter-
nal load attaching means for rotor-
craft-load combinations to be used for
nonhuman external cargo applications
can withstand a limit static load equal
to 2.5, or some lower load factor ap-
proved under §§ 27.337 through 27.341,
multiplied by the maximum external
load for which authorization is re-
quested. It must be shown by analysis,
test, or both that the rotorcraft exter-
nal load attaching means and cor-
responding personnel carrying device
system for rotorcraft-load combina-
tions to be used for human external
cargo applications can withstand a
limit static load equal to 3.5 or some
lower load factor, not less than 2.5, ap-
proved under §§ 27.337 through 27.341,
multiplied by the maximum external
load for which authorization is re-
quested. The load for any rotorcraft-
load combination class, for any exter-
nal cargo type, must be applied in the
vertical direction. For jettisonable ex-
ternal loads of any applicable external
cargo type, the load must also be ap-
plied in any direction making the max-
imum angle with the vertical that can
be achieved in service but not less than
30

. However, the 30

angle may be re-

duced to a lesser angle if—

(1) An operating limitation is estab-

lished limiting external load oper-
ations to such angles for which compli-
ance with this paragraph has been
shown; or

(2) It is shown that the lesser angle

can not be exceeded in service.

(b) The external load attaching

means, for jettisonable rotorcraft-load
combinations, must include a quick-re-
lease system to enable the pilot to re-
lease the external load quickly during
flight. The quick-release system must
consist of a primary quick release sub-
system and a backup quick release sub-
system that are isolated from one an-
other. The quick-release system, and
the means by which it is controlled,
must comply with the following:

(1) A control for the primary quick

release subsystem must be installed ei-
ther on one of the pilot’s primary con-
trols or in an equivalently accessible

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§ 27.873

location and must be designed and lo-
cated so that it may be operated by ei-
ther the pilot or a crewmember with-
out hazardously limiting the ability to
control the rotorcraft during an emer-
gency situation.

(2) A control for the backup quick re-

lease subsystem, readily accessible to
either the pilot or another crew-
member, must be provided.

(3) Both the primary and backup

quick release subsystems must—

(i) Be reliable, durable, and function

properly with all external loads up to
and including the maximum external
limit load for which authorization is
requested.

(ii) Be protected against electro-

magnetic interference (EMI) from ex-
ternal and internal sources and against
lightning to prevent inadvertent load
release.

(A) The minimum level of protection

required for jettisonable rotorcraft-
load combinations used for nonhuman
external cargo is a radio frequency
field strength of 20 volts per meter.

(B) The minimum level of protection

required for jettisonable rotorcraft-
load combinations used for human ex-
ternal cargo is a radio frequency field
strength of 200 volts per meter.

(iii) Be protected against any failure

that could be induced by a failure mode
of any other electrical or mechanical
rotorcraft system.

to be used for human external cargo
applications, the rotorcraft must—

(1) For jettisonable external loads,

have a quick-release system that meets
the requirements of paragraph (b) of
this section and that—

(i) Provides a dual actuation device

for the primary quick release sub-
system, and

(ii) Provides a separate dual actu-

ation device for the backup quick re-
lease subsystem;

(2) Have a reliable, approved per-

sonnel carrying device system that has
the structural capability and personnel
safety features essential for external
occupant safety;

(3) Have placards and markings at all

appropriate locations that clearly state
the essential system operating instruc-
tions and, for the personnel carrying

device system, the ingress and egress
instructions;

(4) Have equipment to allow direct

intercommunication among required
crewmembers and external occupants;
and

(5) Have the appropriate limitations

and procedures incorporated in the
flight manual for conducting human
external cargo operations.

(d) The critically configured jettison-

able external loads must be shown by a
combination of analysis, ground tests,
and flight tests to be both transport-
able and releasable throughout the ap-
proved operational envelope without
hazard to the rotorcraft during normal
flight conditions. In addition, these ex-
ternal loads must be shown to be re-
leasable without hazard to the rotor-
craft during emergency flight condi-
tions.

(e) A placard or marking must be in-

stalled next to the external-load at-
taching means clearly stating any
operational limitations and the max-
imum authorized external load as dem-
onstrated under § 27.25 and this section.

(f) The fatigue evaluation of § 27.571

of this part does not apply to rotor-
craft-load combinations to be used for
nonhuman external cargo except for
the failure of critical structural ele-
ments that would result in a hazard to
the rotorcraft. For rotorcraft-load
combinations to be used for human ex-
ternal cargo, the fatigue evaluation of
§ 27.571 of this part applies to the entire
quick release and personnel carrying
device structural systems and their at-
tachments.

[Amdt. 27–11, 41 FR 55469, Dec. 20, 1976, as
amended by Amdt. 27–26, 55 FR 8001, Mar. 6,
1990; Amdt. 27–36, 64 FR 43019, Aug. 6, 1999]

ISCELLANEOUS

§ 27.871

Leveling marks.

There must be reference marks for

leveling the rotorcraft on the ground.