527 

Federal Aviation Administration, DOT 

§ 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. 

(c) For rotorcraft-load combinations 

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] 

M

ISCELLANEOUS

 

§ 27.871

Leveling marks. 

There must be reference marks for 

leveling the rotorcraft on the ground. 

§ 27.873

Ballast provisions. 

Ballast provisions must be designed 

and constructed to prevent inadvertent 
shifting of ballast in flight. 

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