[Federal Register Volume 63, Number 133 (Monday, July 13, 1998)]
[Proposed Rules]
[Pages 37746-37754]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-18552]



[[Page 37745]]

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Part VII





Department of Transportation





_______________________________________________________________________



Federal Aviation Administration



_______________________________________________________________________



14 CFR Parts 27 and 29



Rotorcraft Load Combination Safety Requirements; Proposed Rule

  Federal Register / Vol. 63, No. 133 / Monday, July 13, 1998 / 
Proposed Rules  

[[Page 37746]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Parts 27 and 29

[Docket No. 29277; Notice No.98-6]
RIN 2120-AG59


Rotorcraft Load Combination Safety Requirements

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking.

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SUMMARY: This document proposes the amendment of the airworthiness 
standards for rotorcraft load combination (RLC) certification. This 
proposal would revise the safety requirements for RLC's to address 
advances in technology and to provide an increased level of safety in 
the carriage of humans. These proposed amendments would provide an 
improvement in the safety standards for RLC certification and lead to a 
harmonized international standard.

DATES: Comments must be submitted on or before October 13, 1998.

ADDRESSES: Comments on this proposed rule may be delivered or mailed in 
triplicate to: Federal Aviation Administration (FAA), Office of the 
Chief Counsel, Attn: Rules Docket (AGC-200), Docket No. 29277, Room 
915G, 800 Independence Avenue, SW., Washington, DC 20591. Comments 
delivered must be marked Docket No. 29277. Comments may also be sent 
electronically to the following internet address: 9-nprm-
[email protected]. Comments may be examined in Room 915G on weekdays 
between 8:30 a.m. and 5:00 p.m., except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Mr. Mike Mathias, Rotorcraft 
Directorate, Aircraft Certification Service, Regulations Group, FAA, 
Fort Worth, Texas 76193-0111, telephone (817) 222-5123.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to submit written data, views, or 
arguments on this proposed rule. Comments relating to the 
environmental, energy, federalism, or economic impact that might result 
from adopting the proposals in this notice are also invited. 
Substantive comments should be accompanied by cost estimates. Comments 
should identify the regulatory docket number and should be submitted in 
triplicate to the Rules Docket address specified above.
    All comments received on or before the closing date for comments 
specified will be considered by the Administrator before taking action 
on this proposed rulemaking. Late-filed comments will be considered to 
the extent practicable. The proposals contained in this notice may be 
changed in light of the comments received.
    All comments received, as well as a report summarizing each 
substantive public contact with FAA personnel on this rulemaking, will 
be filed in the docket. The docket is available for public inspection 
before and after the comment closing date.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must include a preaddressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket No. 29277.'' The postcard will be date stamped and returned 
to the commenter.

Availability of NPRM's

    An electronic copy of this document may be downloaded using a modem 
and suitable communications software from the FAA regulations section 
of the Fedworld electronic bulletin board service (telephone: 703-321-
3339), the Federal Register's electronic bulletin board service 
(telephone: 202-512-1661), or the FAA's Aviation Rulemaking Advisory 
Committee Bulletin Board service (telephone: 800-322-2722 or (202) 267-
5948).
    Internet users may reach the FAA's web page at http://www.faa.gov/
avr/arm/nprm/nprm.htm or the Federal Register's web page at http://
www.access.gpo.gov/su_docs/aces/aces140.html for access to recently 
published rulemaking documents.
    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Office of Rulemaking, ARM-1, 800 Independence Avenue, SW., 
Washington DC 20591, or by calling (202) 267-9680. Communications must 
identify the notice number of this NPRM.
    Persons interested in being placed on a mailing list for future 
NPRM's should request a copy of Advisory Circular No. 11-2A, Notice of 
Proposed Rulemaking Distribution System, which describes the 
application procedures.

History

    For many years the design standards for external load attaching 
means for normal and transport category rotorcraft were contained in 
Subpart D, Airworthiness Requirements of 14 CFR part 133 (part 133), 
Rotorcraft External Load Operations. However, these design standards 
more appropriately belonged under parts 27 and 29. Amendments 27-11 (41 
FR 55469, December 20, 1976) and 29-12 (41 FR 55454, December 20, 1976) 
added new Secs. 27.865 and 29.865 and moved some of these design 
standards from the operational rules of part 133 to the certification 
rules of parts 27 and 29.
    Rotorcraft-load combination classes (RLC) are defined in 14 CFR 
1.1. Part 133 prohibits the carrying of humans, except for crewmembers, 
external to the aircraft under all existing RLC's (A, B, or C). 
However, on April 5, 1978, Exemption No. 2534 was granted to permit 
carrying harbor pilots external to the rotorcraft using a hoist and 
sling.
    Because of the proven public utility of the operations conducted 
with Exemption No. 2534, in January 1987, after notice and a public 
meeting, Amendment 133-9 (51 FR 40707, November 7, 1986) was adopted. 
Amendment 133-9 established provisions for a new Class D RLC for 
transporting external loads other than Classes A, B, or C. Class D may 
apply to either human or nonhuman external cargo operations; however, 
under Amendment 133-9, Sec. 133.45(e) specifies that only certain 
Transport Category A rotorcraft can be used for RLC Class D external 
load operations. Also, Amendment 133-9 added Sec. 133.35 to establish 
specific limitations and the necessary safety requirements for routine 
external load transportation under Class D.

Aviation Rulemaking Advisory Committee (ARAC) involvement

    In 1991 the FAA requested that ARAC study the need to revise the 
regulations on RLC in light of advancements in technology and 
operational procedures and to develop regulatory recommendations. The 
ARAC was established on February 5, 1991 (56 FR 2190, January 22, 
1991), to assist the FAA in the rulemaking process by providing advice 
from the private sector on major regulatory issues affecting aviation 
safety. The ARAC includes representatives of manufacturers, air 
carriers, general aviation, industry associations, labor groups, 
universities, and the general public. The ARAC's formation has given 
the FAA additional opportunities to solicit information directly from 
significantly affected parties who meet and exchange ideas about 
proposed and existing rules that should be either created, revised, or 
eliminated.
    On November 27, 1992, following an announcement in the Federal 
Register (56 FR 63546, December 4, 1991), the ARAC charged The External 
Load

[[Page 37747]]

Working Group with making a recommendation to the ARAC concerning 
whether new or revised airworthiness standards are appropriate for 
Class D rotorcraft external loads, as follows: ``Should parts 27 or 29 
be amended to incorporate Class D external load attaching means, to 
complement Amendment 133-9, which authorizes the transport of 
passengers external to the rotorcraft, with certain conditions and 
limitations?''
    The working group, chaired by a representative from McDonnell 
Douglas Helicopter Systems, included technical specialists 
knowledgeable in both military and civil external load operations, in 
external load and emergency rescue equipment design and manufacturing, 
and in both FAA and industry external load design and operational 
requirements. This broad participation is consistent with FAA policy to 
have all known interested parties involved as early as practicable in 
the rulemaking process.
    The working group reviewed unpublished data regarding external 
loads safety issues developed by the FAA as the starting point for 
their discussions. After reviewing the unpublished data, the working 
group determined that it was necessary to do further research and to 
include consideration of more diverse design configurations and 
operating procedures.
    The working group reviewed current methods that the military and 
other nations' airworthiness authorities use to certificate aircraft 
conducting external load operations. The group also evaluated current 
operational practices with aircraft certificated in all categories and 
public aircraft operations involving human and nonhuman external loads. 
The working group researched available military and domestic safety 
standards and guidance, the accident and incident history of external 
load operations conducted under current certification standards, and 
the specific safety requirements necessary for human and nonhuman 
external load operations in each RLC class.

Technical Research

    The following material was researched by the ARAC working group and 
contributed significantly to formulating these proposals. Copies may be 
found in Rules Docket No. 29277.
    1. United States Army Material Command (USA, AMC) Pamphlet No. 706-
203, ``Engineering Design Handbook Helicopter Engineering, Part Three, 
Qualification Assurance,'' Headquarters United States Army Material 
Command, Washington, D.C. 20315.
    2. USAAVSCOM TR 89-D-22A, ``Aircraft Crash Survival Design Guide; 
Volume IV--Aircraft Seats, Restraints, Litters, and Cockpit/Cabin 
Delethalization.''
    3. MIL-STD-882B, ``Military Standard-System Safety Program 
Requirements,'' March 30, 1984.
    4. MIL-STD-1472D, ``Military Standard-Human Engineering Design 
Criteria for Military Systems, Equipment, and Facilities,'' March 14, 
1989.
    5. British Civil Airworthiness Requirements 29, Issue 1, December 
17, 1986.
    6. Advisory Circular 133-1A, ``Rotorcraft External-Load Operations 
in Accordance with part 133,'' October 16, 1979.
    7. ``Rotorcraft Use in Disaster Relief and Mass Casualty Incidents-
Case Studies,'' DOT/FAA/RD-90/10, June 1990.
    8. ``Guidelines for Integrating Helicopter Assets into Emergency 
Planning,'' DOT/FAA/RD-90/11, July 1991.
    9. FAA Order 8700.1, ``General Aviation Operations Inspector's 
Handbook'' Chapter 96, Change 8, March 1, 1992.
    The research centered on the following:
    (1) Current methods used by the military to qualify external loads;
    (2) Current methods used by the world's airworthiness authorities 
for certification of external loads;
    (3) Current practice in restricted category and public use 
operations regarding human and nonhuman external load operations;
    (4) Load retention and release devices that exist and are 
certifiable;
    (5) Current military and domestic safety standards and guidance;
    (6) Accident and incident history of external load operations that 
relate to the current certification standards; and
    (7) Specific certification safety requirements that are necessary 
for human versus nonhuman external load operations.

Statement of the Issues

    Although rotorcraft external load operations are routinely 
conducted in a safe manner under the existing safety standards, several 
preventable accidents and incidents have occurred during the preceding 
decade. For example, several preventable inadvertent releases of humans 
being carried external to the rotorcraft have occurred due to the lack 
of specific safety standards for quick-release systems (QRS). 
Additionally, the equipment employed in external load operations has 
changed significantly since the existing safety standards were 
promulgated. Examples of these equipment changes are more diverse, 
maneuverable, and powerful rotorcraft designs, new QRS designs, new 
personnel carrying device systems (PCDS) designs, and new methods of 
rigging external loads to the rotorcraft.
    Because of the need for both modernization and a higher level of 
safety, this proposal would address safety requirements for human 
external cargo (HEC) and nonhuman external cargo (NHEC); update load-
to-vertical-angle certification requirements; add reliability and 
durability requirements for external load retention and release systems 
and devices; and add electromagnetic interference and lightning 
protection requirements because these items are not specifically 
addressed in the existing regulations.
    In addition, this proposal would amend part 29 by adding new 
certification requirements that are compatible with the operating 
requirements of current part 133 for RLC Class D external loads. This 
proposal would provide a clearly specified certification safety 
standard for RLC Class D external loads in part 29. The change to part 
29 would respond to increasing public demand for specific RLC Class D 
provisions that meet operational needs through standardized 
certification criteria.
    Studies and analyses of service difficulty reports and the 
introduction of modern external load equipment and operational 
practices have shown a need for updating the regulations to (1) 
significantly decrease the potential for future accidents and 
incidents; (2) ensure that external cargo load carrying devices, their 
release mechanisms, their load carrying systems, and their flight 
performance, reflect modern operational needs; and (3) provide updated 
standards that can be harmonized with the Joint Airworthiness 
Regulations (JAR).

Current Requirements

    Currently, Secs. 27.865 and 29.865 contain identical provisions and 
apply only to RLC Class A, B, and C loads at the gross weights and 
associated load factors common for relatively heavy NHEC loads. Primary 
and secondary quick-release devices are required; however, specific 
safety features and test and reliability requirements for the entire 
QRS are not specified. In-flight handling qualities and release (i.e., 
jettisonability) characteristics of NHEC and HEC are not currently 
addressed.

[[Page 37748]]

    Part 29 Transport Category A rotorcraft are eligible under part 133 
for Class D RLC operations. However, part 29 design standards do not 
exist for certification of Class D RLC's.

FAA Evaluation of ARAC Recommendation

    After reviewing the External Load Working Group's work product and 
the ARAC recommendations, the FAA has determined that parts 27 and 29 
should be revised to establish an increased margin of safety in 
rotorcraft external load operations. These revisions are necessary to 
implement modern safety standards that accommodate current and 
anticipated operational RLC applications and procedures and provide 
separate levels of safety for NHEC and HEC RLC's. These new safety 
standards are more fully described in the General Discussion of 
Proposals section. These changes to parts 27 and 29 include the 
addition of: (1) increased load factors for HEC; (2) increased QRS 
safety standards for both NHEC and HEC; (3) new PCDS standards for HEC; 
(4) new flight-handling characteristic standards for both NHEC and HEC; 
(5) increased fatigue substantiation standards for both NHEC and HEC; 
and (6) to part 29 only, the RLC Class D standard. These improvements 
to the safety standards should prevent many accidents and incidents. 
The proposal would provide identical, improved external load standards 
for rotorcraft certificated under parts 27 and 29 and would provide RLC 
Class D certification standards under part 29.

General Discussion of Proposals

    These proposals would provide essentially identical external load 
standards in parts 27 and 29. In addition, both the part 27 and 29 
proposals would provide certification standards for all RLC's that are 
compatible with the operational requirements in part 133.

Proposed Amendments to Secs. 27.25(c) and 29.25(c)

    The proposed amendments to Secs. 27.25 and 29.25 would limit the 
availability of increased gross weights to those RLC's that involve the 
carriage of nonhuman loads. For applications for certification with 
human loads, the applicant would be limited by subparagraph (c)(1) to 
the maximum weight established in Sec. 27.25(a). The changes would be a 
new limitation to reflect the distinction being made between those 
operations involving the carrying of humans externally for which a 
higher level of safety is needed.

Proposed Amendments to Secs. 27.865 and 29.865

    Because the proposed amendments would address more than just the 
attachment means for external loads, the undesignated center headings 
and the section titles of proposed Secs. 27.865 and 29.865 would be 
changed from ``External Load Attaching Means'' to ``External Loads.''

Proposed Amendments to Secs. 27.865(a) and 29.865(a)

    The addition of new human external cargo certification requirements 
(HEC) and additional requirements for nonhuman external cargo (NHEC) 
certification results in modification of Secs. 27.865(a) and 29.865(a). 
The most significant modification is a change in the current load 
factor specification to distinguish between and provide the required 
additional level of safety for HEC.
    Current Secs. 27.865(a) and 29.865(a) require the use of a 2.5g 
vertical limit load factor or a lesser value (derived from current 
Secs. 27.337 through 27.341 or 29.337 through 29.341) at the maximum 
external load value for which certification is requested. This 2.5g 
limit load factor would be retained for NHEC applications in the 
proposals.
    However, for HEC applications that are typically lower gross weight 
configurations, proposed Secs. 27.865(a) and 29.865(a) contain a higher 
vertical limit load factor to be applied to the external load 
attachment and the entire attached PCDS. The higher vertical limit load 
factor is specified by these proposals as either the analytically 
derived maximum vertical limit load factor for the proposed operating 
envelope or a vertical limit load factor of 3.5 (derived from 
Secs. 27.337 and 29.337). However, in no case would these proposals 
allow the maximum vertical limit load factor for HEC to be less than 
2.5. Linear interpolation between minimum and maximum vertical design 
load factors and standard operating gross weight is one simple, 
acceptable means to determine design limit load factors.
    Proposed Secs. 27.865(a) and 29.865(a) would also require the limit 
static load for any RLC, either HEC or NHEC, to be determined and 
applied in both the vertical direction, and for jettisonable external 
loads in any direction, making the maximum angle that can be achieved 
in service (but not less than 30 deg.) with the vertical axis of the 
rotorcraft. The term ``maximum angle that can be achieved in service'' 
means the largest angle expected to occur during normal operation. This 
term is added to the vertical angle requirement to ensure that sidepull 
(or other) configurations used for jettisonable RLC applications, such 
as wire stringing, that typically involve angles greater than the 
current 30 deg., would be addressed at the time of certification. The 
current 30 deg. angle requirement was established based on the rule-of-
thumb design limit for winch or hoist applications typical when the 
rule was promulgated and applications using larger angles were 
unforeseen. The proposed rule would not change the 30 deg. angle 
limitation for winch or hoist applications. The existing rule does not 
specifically address RLC applications such as sidepull configurations. 
These proposed section changes would more closely match the needed 
safety standards to the type of RLC operations in the industry.

Proposed Amendments to Secs. 27.865(b) and 29.865(b)

    The terms ``quick-release system,'' ``primary quick release 
subsystem,'' and ``backup quick release subsystem'' are substituted 
throughout proposed Secs. 27.865(b) and 29.865(b) for the current 
terminology of quick-release device, primary quick-release device, and 
mechanical backup quick-release device to require certification of the 
entire QRS, not just the quick-release devices. The proposals would 
also require that the primary and backup QRS be isolated from one 
another to ensure fail safety.
    Also to facilitate harmonization with the Joint Aviation 
Authorities (JAA), the FAA proposes to delete the current references to 
RLC Classes B and C from Secs. 27.865(b) and 29.865(b). These 
references are not necessary to the proposed new Secs. 27.865(b) and 
29.865(b) because the design distinctions necessary to provide the 
required level of safety would be made during certification without a 
need to refer to the operations based RLC classes. These distinctions 
are made by specifying whether or not an external load is jettisonable 
or non-jettisonable and whether or not an external load is human or 
non-human.

Proposed Amendments to Secs. 27.865(b)(1) and 29.865(b)(1)

    Proposed Secs. 27.865(b)(1) and 29.865(b)(1) would allow the 
primary quick release control to be mounted either on a primary control 
or in any equivalently accessible location. This proposed change is 
intended to liberalize design options and allow a more realistic 
workload distribution among larger dedicated crews while maintaining 
the same level-of-safety.

[[Page 37749]]

The proposals would allow the control to be operated by a crewmember 
without necessarily being reachable by the pilot. The rotorcraft's 
approved operating procedures must address the responsibilities and 
procedures for the control of the QRS.

Proposed Amendments to Secs. 27.865(b)(2) and 29.865(b)(2)

    Proposed Secs. 27.865(b)(2) and 29.865(b)(2) would change the 
current requirement that the backup control for the quick-release 
device be only a manual mechanical control. These proposals would 
require that a backup quick release subsystem of an approved design be 
readily available to the pilot or other crewmember.

Proposed Amendments to Secs. 27.865(b)(3)(i) and 29.865(b)(3)(i)

    Because of adverse service history and the need to specifically 
distinguish the levels of safety for HEC and NHEC, proposed 
Secs. 27.865(b)(3)(i) and 29.865(b)(3)(i) would require that both the 
primary and backup quick release subsystems be reliable, durable, and 
functional. Reliability would be demonstrated by use of design features 
and by use of failure modes and effects analysis. Both reliability and 
durability would be demonstrated by use of repetitive functional tests. 
These proposed reliability and durability criteria would apply only to 
newly modified or type certificated helicopters equipped with external 
load attachment provisions or devices or both.

Proposed Amendments to Secs. 27.865(b)(3)(ii) and 29.865(b)(3)(ii)

    Proposed Secs. 27.865(b)(3)(ii) and 29.865(b)(3)(ii) would require 
protection of the quick-release subsystems against potential internal 
and external sources of electromagnetic interference (EMI) and 
lightning. The new requirements are necessary to prevent inadvertent 
jettison of NHEC and HEC from sources such as stray electromagnetic 
signals, static electricity, and lightning strikes. Proposed field 
intensity levels are 200 volts per meter for applicable portions of QRS 
used for HEC and 20 volts per meter for applicable portions of QRS used 
for NHEC. The purpose of the requirements is for those applicable 
portions of the QRS to withstand these field intensity levels without 
inadvertent load release.

Proposed Amendments to Secs. 27.865(b)(3)(iii) and 29.865(b)(3)(iii)

    Proposed Secs. 27.865(b)(3)(iii) and 29.865(b)(3)(iii) would 
require that the quick-release subsystems be protected against failures 
that could occur as a result of an electrical or mechanical malfunction 
of other rotorcraft components.

Proposed Amendments to Secs. 27.865(c) and 29.865(c).

    This proposal would redesignate existing Secs. 27.865(c) and 
29.865(c) as Secs. 27.865(e) and 29.865(e), respectively. New 
Secs. 27.865(c) and 29.865(c) are proposed to separately address the 
safety requirements for HEC carriage. The new requirements would ensure 
that the HEC certification requirements are clearly and properly 
identified.

Proposed Amendments Secs. 27.865(c)(1) and 29.865(c)(1)

    Proposed Secs. 27.865(c)(1) and 29.865(c)(1) would require that the 
HEC load release primary and backup controls meet the requirements of 
Secs. 27.865(b) and 29.865(b), respectively, and that both controls be 
designed to require dual actuation (i.e., require two distinct actions) 
for load release. This is necessary to mitigate inadvertent HEC 
release.

Proposed Amendments to Secs. 27.865(c)(2) and 29.865(c)(2)

    Proposed Secs. 27.865(c)(2) and 29.865(c)(2) would require that the 
applicant demonstrate that the PCDS is reliable in accordance with the 
HEC provisions of Secs. 27.865(b)(3)(i) and 29.865(b)(3)(i), 
respectively; has the structural capability required under 
Secs. 27.865(a) and 29.865(a), respectively; and has the essential 
personnel safety provisions (based on the design configuration of the 
PCDS) to minimize hazards to occupants carried external to the 
rotorcraft.

Proposed Amendments to Secs. 27.865(c)(3) and 29.865(c)(3)

    Proposed Secs. 27.865(c)(3) and 29.865(c)(3) would require that all 
necessary placards and markings be provided and be properly located to 
facilitate their proper use and, for the PCDS, to clearly specify the 
ingress and egress instructions.

Proposed Amendments to Secs. 27.865(c)(4) and 29.865(c)(4)

    Proposed Secs. 27.865(c)(4) and 29.865(c)(4) would require that an 
intercom system or other approved equipment be installed to ensure 
proper communication among crewmembers and occupants during an 
emergency. For simple rescue systems that do not have intercom systems 
mandated by operating regulations, voice signals or hand signals to 
PCDS occupants may be acceptable. In more complex systems, it is 
intended that more sophisticated communication systems, such as 
intercoms, be provided.

Proposed Amendments to Secs. 27.865(c)(5) and 29.865(c)(5)

    Proposed Secs. 27.865(c)(5) and 29.865(c)(5) would require that all 
flight limitations and procedures for HEC operations be identified and 
incorporated in the flight manual.

Proposed Amendment to Sec. 29.865(c)(6)

    To be compatible with part 133.45(e), proposed Sec. 29.865(c)(6) 
would require, for HEC operations that require the use of Category A 
rotorcraft only (Class D RLC), that one-engine-inoperative hover 
performance capability information based on a dynamic engine failure 
(simulated engine failure in an actual test rotorcraft) be provided in 
the flight manual for the operating weights, altitudes, and 
temperatures for which external load approval is requested.

Proposed Amendments Secs. 27.865(d) and 29.865(d).

    Proposed new Secs. 27.865(d) and 29.865(d) would require that 
critically configured jettisonable external loads (class and type) must 
be shown to be both transportable and releasable without hazard to the 
rotorcraft during normal flight conditions. In addition, these external 
loads must be shown to be releasable without hazard to the rotorcraft 
during emergency flight conditions. Compliance with the proposed 
requirements can be accomplished by using a combination of analysis, 
ground tests, and flight tests. This is necessary to ensure that the 
extremities of the operating range are thoroughly explored without 
unnecessary risk and cost. The new provisions would mitigate HEC 
transport problems such as entanglements with the rotorcraft in flight 
and will provide a mandatory flight test validation of the QRS. Current 
Secs. 27.865(d) and 29.865(d) would be revised and redesignated as 
Secs. 27.865(f) and 29.865(f), respectively.

Proposed Amendments to Secs. 27.865(e) and 29.865(e)

    Current Secs. 27.865(c) and 29.865(c) would be revised and 
redesignated as Secs. 27.865(e) and 29.865(e), respectively. The 
proposals would amend these sections by adding a requirement to install 
a placard next to the external load attaching means that specifies any 
operational limitations in addition to the maximum authorized external 
load weight that can be attached.

[[Page 37750]]

Proposed Amendments to Secs. 27.865(f) and 29.865(f)

    Sections 27.865(d) and 29.865(d) would be revised and redesignated 
as Secs. 27.865(f) and 29.865(f), respectively. These paragraphs would 
require that for NHEC, all critical structural elements such as those 
in the external load attachment and carrying system whose failure would 
result in a hazard to the rotorcraft (not just the cargo hook) have a 
fatigue analysis in accordance with Secs. 27.571 and 29.571, as 
applicable. The proposals would also require that for HEC, the entire 
QRS and PCDS and their attachments to the rotorcraft have a fatigue 
analysis in accordance with Secs. 27.571 or 29.571, as applicable.

Paperwork Reduction Act

    In accordance with the Paperwork Reduction Act of 1995 (44 U.S.C. 
Sec. 3507(d)), there are no requirements for information collection 
associated with this final rule.

International Compatibility

    The FAA has reviewed corresponding International Civil Aviation 
Organization international standards and recommended practices and 
Joint Aviation Authorities regulations, where they exist, and has 
identified no differences in these proposed amendments and the foreign 
regulations.

Regulatory Evaluation Summary

    Changes to federal regulations must undergo several economic 
analyses. First, Executive Order 12866 directs that each Federal agency 
shall propose or adopt a regulation only upon a reasoned determination 
that the benefits of the intended regulation justify its costs. Second, 
the Regulatory Flexibility Act of 1980 requires agencies to analyze the 
economic impact of regulatory changes on small entities. Third, the 
Office of Management and Budget directs agencies to assess the effects 
of regulatory changes on international trade. Fourth, the Unfunded 
Mandates Reform Act of 1995 (Pub. L. 104-4) requires agencies to 
prepare a written assessment of the costs, benefits and other effects 
of proposed or final rules that include a Federal mandate likely to 
result in the expenditure by State, local or tribal governments, in the 
aggregate, or by the private sector, of $100 million or more annually 
(adjusted for inflation). In conducting these analyses, which are 
summarized as follows (and available in the docket), the FAA has 
determined that this NPRM is not a ``significant regulatory action'' 
under section 3(f) of Executive Order 12866 and therefore was not 
reviewed by the Office of Management and Budget. This NPRM is not 
considered significant under Department of Transportation's Policies 
and Procedures (44 FR 11034, February 26, 1979). In addition, for the 
reasons stated under the ``Trade Impact Statement'' and the 
``Regulatory Flexibility Determination,'' the FAA certifies that this 
NPRM will not have a significant economic impact on a substantial 
number of small entities and would not result in the expenditure by 
State, local or tribal governments, in the aggregate, or by the private 
sector, of $100 million or more annually.
    The FAA invites the public to provide comments (and related data) 
on the assumptions made in this evaluation. All comments received will 
be considered in the final regulatory evaluation.

Costs and Benefits

Costs
    The costs of the proposed rule, which would be borne by 
manufacturers and operators, are evaluated for the time period 
extending from its implementation date through the operating lives of 
75 rotorcraft assumed to be produced under four new type certificates 
(involving 15-year production runs of 5 rotorcraft per year total under 
all four new type certificates) and placed into part 133 service. Over 
the course of this evaluation period, incremental costs would total 
approximately $388,500 (1996 dollars), or $203,000 discounted to 
present value (using an interest rate of seven percent and letting 
``present'' be the date of initial type certification application). Of 
the $388,500 total cost, $156,000 is attributable to incremental 
design, analysis, test, and other certification costs, $30,000 to 
incremental production costs (75 rotorcraft at $400 each), and $202,500 
to incremental weight penalty fuel costs ($180 per year per rotorcraft 
over 15-year operating lives of 75 rotorcraft). On a per-rotorcraft 
basis, costs would average approximately $5,200, or $2,700 discounted. 
These incremental costs would be offset to some extent by potential 
cost savings associated with the harmonization of these proposals with 
the JAA and eventual creation of identical JAA airworthiness standards, 
streamlining of certification approvals for part 133 operators, and 
some relaxed requirements for parts 27 and 29 manufacturers (see 
Benefits section, below).
Benefits
    To estimate the safety benefits of the proposed rule, the FAA 
reviewed records of accidents involving part 133 operators that 
occurred between mid-1983 and mid-1994 that could have been prevented 
or the losses reduced if the proposed changes were in effect. During 
the 11-year period, there were 17 such accidents involving fatal and/or 
non-fatal injuries, or damage to equipment, or both. Eight of the 
accidents resulted in harm to persons (either inside or outside of the 
rotorcraft), totaling eight fatalities and two serious injuries. 
Fifteen of the 17 accidents involved either substantial damage (seven) 
or destruction of the rotorcraft (eight).
    To provide a basis for comparing the safety benefits and costs of 
rulemaking actions, the FAA currently uses a minimum statistical value 
of $2.7 million for a fatality avoided and $518,000 for a serious 
injury avoided. Applying these standards to the casualty losses 
summarized above and making allowances for the costs of rotorcraft 
damage, the total cost of the 17 accidents was approximately $27.2 
million.
    The FAA estimates that the proposed rule could prevent at least 50 
percent of the type of accidents summarized above. Applying it 
retrospectively would yield dollar benefits of approximately $13.6 
million (one-half of $27.2 million). Over the 11-year accident 
evaluation period, the part 133 fleet averaged approximately 300 active 
rotorcraft. Therefore, the benefits would average approximately $4,100 
per year per rotorcraft ($13.6 million/11 years/300 operating part 133 
rotorcraft per year). Applying this per-rotorcraft safety benefit to 
the cumulative number of complying rotorcraft results in total safety 
benefits of $4.6 million (or $1.3 million discounted to present value). 
On a per-rotorcraft basis, these benefits would average approximately 
$61,500, or $17,300 discounted.
    In addition to improving safety, the proposed rule would provide 
some cost-relief in certain respects. New production rotorcraft would 
be delivered with standardized procedures for external load operations, 
and could result in a small savings to part 133 operators. Further, 
changes to current regulations that relate to the primary and backup 
quick-release devices would reduce production costs for parts 27 and 29 
rotorcraft manufacturers. The changes would also increase harmonization 
and commonality between U.S. and European airworthiness standards. 
Harmonization would eliminate unnecessary differences in airworthiness 
requirements, thus reducing manufacturers' certification costs.

[[Page 37751]]

Comparison of Costs and Benefits
    The proposed rule would generate benefits in the form of increased 
safety and cost relief (see preceding paragraph--the potential cost 
relief has not been included in the cost/benefit calculation). On a 
per-rotorcraft basis, the life-cycle safety benefits would average 
approximately $17,300 (discounted) and the costs would average 
approximately $2,700 (discounted), yielding a benefit-to-cost ratio of 
6.4 to 1. On this basis alone, the proposed rule is cost-beneficial; 
additional quantified efficiency and harmonization benefits would 
increase this ratio.

Regulatory Flexibility Determination

    The Regulatory Flexibility Act of 1980 (RFA) establishes ``as a 
principle of regulatory issuance that agencies shall endeavor, 
consistent with the objective of the rule and of applicable statutes, 
to fit regulatory and informational requirements to the scale of the 
business, organizations, and governmental jurisdictions subject to 
regulation.'' To achieve that principle, the Act requires agencies to 
solicit and consider flexible regulatory proposals and to explain the 
rationale for their actions. The Act covers a wide-range of small 
entities, including small businesses, not-for-profit organizations and 
small governmental jurisdictions.
    Agencies must perform a review to determine whether a proposed or 
final rule will have a significant economic impact on a substantial 
number of small entities. If the determination is that it will, the 
agency must prepare a regulatory flexibility analysis as described in 
the Act.
    However, if an agency determines that a proposed or final rule is 
not expected to have a significant economic impact on a substantial 
number of small entities, section 605(b) of the 1980 act provides that 
the head of the agency may so certify and an RFA is not required. The 
certification must include a statement providing the factual basis for 
this determination, and the reasoning should be clear.
    The entities that would be affected by the proposed rule consist of 
rotorcraft manufacturers (included in Standard Industrial 
Classification (SIC 3721, Aircraft and Aircraft Parts Manufacturers) 
and external load operators (SIC 4512, 4513, 4522). Manufacturers would 
incur additional development, certification, and production costs. In 
addition to indirectly incurring all or part of these costs in the form 
of higher rotorcraft acquisition costs, operators would incur increased 
fuel costs resulting from weight penalties. Although the certification 
costs (non-recurring) would be either fully absorbed by the 
manufacturer(s), passed on in-total to operator(s) (purchasers), or 
more likely, absorbed in some proportion by both, the FAA in this 
analysis adopts a conservative approach and allocates total 
certification costs to each category in assessing significant economic 
impact. Incremental per-unit production costs, however, are assumed to 
be fully passed on to purchasers (operators).
    For manufacturers, a small entity is one with 1,500 or fewer 
employees. Only five rotorcraft manufacturers have 1,500 or fewer 
employees and therefore qualify as small entities. However, three of 
these are not currently producing new type-certificated rotorcraft, and 
a fourth does not produce rotorcraft used for external loads. The fifth 
small manufacturer produces specialized smaller rotorcraft, a minority 
of which are configured for external load operations; this producer 
does not compete with the larger manufacturers. Annualized 
certification costs imposed by the proposed rule are estimated to be 
$3,800 per manufacturer for each certification and is not considered 
significant within the meaning of the RFA.
    There are numerous external load operators. The FAA has not 
determined how many of these are small operators and if a substantial 
number would potentially be impacted by the proposal. However, most 
external load operations involve specialized activities such as 
logging, offshore oil drilling, or emergency rescue operations, the 
demand for which is highly price-inelastic; the operators can readily 
pass on the incremental costs to their customers. Notwithstanding, the 
maximum annualized cost per rotorcraft would most likely not be greater 
than $314 (includes manufacturers' certification and production costs 
passed on to the purchaser and increased fuel costs, but excludes 
potential offsetting cost-savings). This amount probably equates to 
less than the cost of two hours' operating time (representing a de 
minimus portion of annual revenues) and is not considered significant 
within the meaning of the RFA. In addition, no small manufacturer or 
small operator would bear a disproportionate cost burden nor have a 
greater likelihood of failing in business compared to larger entities.
    Based on the findings delineated above and consistent with the 
objectives and requirements of the RFA as amended, the FAA certifies 
that this proposed rule would not have a significant economic impact on 
a substantial number of small entities. The FAA invites comments on 
this finding (and the underlying assumptions) during the public comment 
period following publication of the subject NPRM.

International Trade Impact Assessment

    Consistent with the Administration's belief in the general 
superiority, desirability, and efficacy of free trade, it is the policy 
of the Administrator to remove or diminish, to the extent feasible, 
barriers to international trade, including both barriers affecting the 
export of American goods and services to foreign countries and those 
affecting the import of foreign goods and services into the United 
States.
    In accordance with that policy, the FAA is committed to develop as 
much as possible its aviation standards and practices in harmony with 
its trading partners. Significant cost savings can result from this, 
both to United States' companies doing business in foreign markets, and 
foreign companies doing business in the United States.
    This proposed rule is a direct action to respond to this policy by 
increasing the harmonization of the U.S. Federal Aviation Regulations 
with the European Joint Aviation Requirements. The result would be a 
positive step toward removing impediments to international trade.

Federalism Implications

    The regulations proposed herein will not have substantial direct 
effects on the states, on the relationship between the national 
government and the states, or on the distribution of power and 
responsibilities among the various levels of government. Therefore, in 
accordance with Executive Order 12612, it is determined that this 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.

Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (the Act), 
enacted as Pub. L. 104-4 on March 22, 1995, requires each Federal 
agency, to the extent permitted by law, to prepare a written assessment 
of the effects of any Federal mandate in a proposed or final agency 
rule that may result in the expenditure by State, local, and tribal 
governments, in the aggregate, or by the private sector, of $100 
million or more (adjusted annually for inflation) in any one year. 
Section 204(a) of the Act, 2 U.S.C. 1534(a), requires the Federal 
agency to develop an effective process to permit timely input by 
elected

[[Page 37752]]

officers (or their designees) of State, local, and tribal governments 
on a proposed ``significant intergovernmental mandate.'' A 
``significant intergovernmental mandate'' under the Act is any 
provision in a Federal agency regulation that will impose an 
enforceable duty upon State, local, and tribal governments, in the 
aggregate, of $100 million (adjusted annually for inflation) in any one 
year. Section 203 of the Act, 2 U.S.C. 1533, which supplements section 
204(a), provides that before establishing any regulatory requirements 
that might significantly or uniquely affect small governments, the 
agency shall have developed a plan that, among other things, provides 
for notice to potentially affected small governments, if any, and for a 
meaningful and timely opportunity to provide input in the development 
of regulatory proposals.
    The FAA determines that this proposed rule does not contain a 
significant intergovernmental or private sector mandate as defined by 
the Act.

List of Subjects

14 CFR Part 27

    Air transportation, Aircraft, Aviation safety, Rotorcraft, Safety.

14 CFR Part 29

    Air transportation, Aircraft, Aviation safety, Rotorcraft, Safety.

The Proposed Amendments

    In consideration of the foregoing, the Federal Aviation 
Administration proposes to amend parts 27 and 29 of Title 14, Code of 
Federal Regulations (14 CFR parts 27 and 29) as follows:

PART 27--AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT

    1. The authority citation for part 27 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701-44702, 44704.

    2. Section 27.25 is amended by revising paragraph (c) to read as 
follows:


Sec. 27.25  Weight limits

* * * * *
    (c) Total weight with jettisonable external load. A total weight 
for the rotorcraft with a jettisonable external load attached that is 
greater than the maximum weight established under paragraph (a) of this 
section may be established for any rotorcraft-load combination if--
    (1) The rotorcraft-load combination does not include human external 
cargo,
    (2) Structural component approval for external load operations 
under either Sec. 27.865, or under equivalent operational standards is 
obtained,
    (3) The portion of the total weight that is greater than the 
maximum weight established under paragraph (a) of this section is made 
up only of the weight of all or part of the jettisonable external load,
    (4) Structural components of the rotorcraft are shown to comply 
with the applicable structural requirements of this part under the 
increased loads and stresses caused by the weight increase over that 
established under paragraph (a) of this section, and
    (5) Operation of the rotorcraft at a total weight greater than the 
maximum certificated weight established under paragraph (a) of this 
section is limited by appropriate operating limitations under 
Sec. 27.865 (a) and (d) of this part.
    3. The undesignated center heading preceding Sec. 27.865 is revised 
as set forth below, and in Sec. 27.865 the section heading, paragraph 
(a) introductory text and paragraph (b) are revised; paragraphs (c) and 
(d) are redesignated as paragraphs (e) and (f) and revised; and new 
paragraphs (c) and (d) are added to read as follows:

External Loads


Sec. 27.865  External loads.

    (a) It must be shown by analysis, test, or both, that the 
rotorcraft external load attaching means for rotorcraft-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 
approved under Secs. 27.337 through 27.341, multiplied by the maximum 
external load for which authorization is requested. It must be shown by 
analysis, test, or both that the rotorcraft external load attaching 
means and corresponding personnel carrying device system for 
rotorcraft-load combinations 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, approved under Secs. 27.337 
through 27.341, multiplied by the maximum external load for which 
authorization is requested. The load for any rotorcraft-load 
combination class, for any external cargo type, must be applied in the 
vertical direction. For jettisonable external loads of any applicable 
external cargo type, the load must also be applied in any direction 
making the maximum angle with the vertical that can be achieved in 
service but not less than 30 deg.. However, the 30 deg. angle may be 
reduced to a lesser angle if--
* * * * *
    (b) The external load attaching means, for jettisonable rotorcraft-
load combinations, must include a quick-release system to enable the 
pilot to release the external load quickly during flight. The quick-
release system must consist of a primary quick release subsystem and a 
backup quick release subsystem that are isolated from one another. 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 either on one of the pilot's primary controls or in an 
equivalently accessible location and must be designed and located so 
that it may be operated by either the pilot or a crewmember without 
hazardously limiting the ability to control the rotorcraft during an 
emergency situation.
    (2) A control for the backup quick release subsystem, readily 
accessible to either the pilot or another crewmember, 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 load for which 
authorization is requested.
    (ii) Be protected against electromagnetic interference (EMI) from 
external 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 external 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 
subsystem, and
    (ii) Provides a separate dual actuation device for the backup quick 
release subsystem.
    (2) Have a reliable, approved personnel carrying device system that 
has the structural capability and

[[Page 37753]]

personnel safety features essential for external occupant safety,
    (3) Have placards and markings at all appropriate locations that 
clearly state the essential system operating instructions 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 jettisonable external loads must be 
shown by a combination of analysis, ground tests, and flight tests to 
be both transportable and releasable throughout the approved 
operational envelope without hazard to the rotorcraft during normal 
flight conditions. In addition, these external loads must be shown to 
be releasable without hazard to the rotorcraft during emergency flight 
conditions.
    (e) A placard or marking must be installed next to the external-
load attaching means clearly stating any operational limitations and 
the maximum authorized external load as demonstrated under Sec. 27.25 
and this section.
    (f) The fatigue evaluation of Sec. 27.571 of this part does not 
apply to rotorcraft-load combinations to be used for nonhuman external 
cargo except for the failure of critical structural elements that would 
result in a hazard to the rotorcraft. For rotorcraft-load combinations 
to be used for human external cargo, the fatigue evaluation of 
Sec. 27.571 of this part applies to the entire quick release and 
personnel carrying device structural systems and their attachments.

PART 29--AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT

    4. The authority citation for part 29 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701-44702, 44704.


Sec. 29.25  [Amended]

    5. Section 29.25 is amended by revising paragraph (c) to read as 
follows:
* * * * *
    (c) Total weight with jettisonable external load. A total weight 
for the rotorcraft with a jettisonable external load attached that is 
greater than the maximum weight established under paragraph (a) of this 
section may be established for any rotorcraft-load combination if--
    (1) The rotorcraft-load combination does not include human external 
cargo,
    (2) Structural component approval for external load operations 
under either Sec. 29.865 or under equivalent operational standards is 
obtained,
    (3) The portion of the total weight that is greater than the 
maximum weight established under paragraph (a) of this section is made 
up only of the weight of all or part of the jettisonable external load,
    (4) Structural components of the rotorcraft are shown to comply 
with the applicable structural requirements of this part under the 
increased loads and stresses caused by the weight increase over that 
established under paragraph (a) of this section, and
    (5) Operation of the rotorcraft at a total weight greater than the 
maximum certificated weight established under paragraph (a) of this 
section is limited by appropriate operating limitations under 
Sec. 29.865 (a) and (d) of this part.
    6. The undesignated center heading preceding Sec. 29.865 is revised 
as set forth below, and in Sec. 29.865 the section heading, paragraph 
(a) introductory text and paragraph (b) are revised; paragraphs (c) and 
(d) are redesignated as paragraphs (e) and (f) and revised; and new 
paragraphs (c) and (d) are added to read as follows:

External Loads


Sec. 29.865  External loads.

    (a) It must be shown by analysis, test, or both, that the 
rotorcraft external load attaching means for rotorcraft-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 
approved under Secs. 29.337 through 29.341, multiplied by the maximum 
external load for which authorization is requested. It must be shown by 
analysis, test, or both that the rotorcraft external load attaching 
means and corresponding personnel carrying device system for 
rotorcraft-load combinations 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, approved under Secs. 29.337 
through 29.341, multiplied by the maximum external load for which 
authorization is requested. The load for any rotorcraft-load 
combination class, for any external cargo type, must be applied in the 
vertical direction. For jettisonable external loads of any applicable 
external cargo type, the load must also be applied in any direction 
making the maximum angle with the vertical that can be achieved in 
service but not less than 30 deg.. However, the 30 deg. angle may be 
reduced to a lesser angle if--
* * * * *
    (b) The external load attaching means, for jettisonable rotorcraft-
load combinations, must include a quick-release system to enable the 
pilot to release the external load quickly during flight. The quick-
release system must consist of a primary quick release subsystem and a 
backup quick release subsystem that are isolated from one another. 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 either on one of the pilot's primary controls or in an 
equivalently accessible location and must be designed and located so 
that it may be operated by either the pilot or a crewmember without 
hazardously limiting the ability to control the rotorcraft during an 
emergency situation.
    (2) A control for the backup quick release subsystem, readily 
accessible to either the pilot or another crewmember, 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 load for which 
authorization is requested.
    (ii) Be protected against electromagnetic interference (EMI) from 
external 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 external 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 
subsystem, and

[[Page 37754]]

    (ii) Provides a separate dual actuation device for the backup quick 
release subsystem.
    (2) Have a reliable, approved personnel 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 instructions and, for the 
personnel carrying device system, ingress and egress instructions,
    (4) Have equipment to allow direct intercommunication among 
required crewmembers and external occupants,
    (5) Have the appropriate limitations and procedures incorporated in 
the flight manual for conducting human external cargo operations, and
    (6) For human external cargo applications requiring use of Category 
A rotorcraft, have one-engine-inoperative hover performance data and 
procedures in the flight manual for the weights, altitudes, and 
temperatures for which external load approval is requested.
    (d) The critically configured jettisonable external loads must be 
shown by a combination of analysis, ground tests, and flight tests to 
be both transportable and releasable throughout the approved 
operational envelope without hazard to the rotorcraft during normal 
flight conditions. In addition, these external loads must be shown to 
be releasable without hazard to the rotorcraft during emergency flight 
conditions.
    (e) A placard or marking must be installed next to the external-
load attaching means clearly stating any operational limitations and 
the maximum authorized external load as demonstrated under Sec. 29.25 
and this section.
    (f) The fatigue evaluation of Sec. 29.571 of this part does not 
apply to rotorcraft-load combinations to be used for nonhuman external 
cargo except for the failure of critical structural elements that would 
result in a hazard to the rotorcraft. For rotorcraft-load combinations 
to be used for human external cargo, the fatigue evaluation of 
Sec. 29.571 of this part applies to the entire quick release and 
personnel carrying device structural systems and their attachments.

    Issued in Washington, DC, on July 6, 1998.
Thomas E. McSweeney,
Director, Aircraft Certification Service.
[FR Doc. 98-18552 Filed 7-10-98; 8:45 am]
BILLING CODE 4910-13-P