Normal and Transport Category Rotorcraft Certification, 50583-50593 [2017-23360]

Agencies

• Federal Aviation Administration
• DEPARTMENT OF TRANSPORTATION

[Federal Register Volume 82, Number 210 (Wednesday, November 1, 2017)]
[Proposed Rules]
[Pages 50583-50593]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-23360]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Parts 27 and 29

[Docket No.: FAA-2017-0990]
RIN 2120-AK80


Normal and Transport Category Rotorcraft Certification

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to amend the certification standards of 
normal and transport category helicopters. The proposed changes are 
necessary to address modern designs currently used in the rotorcraft 
industry and would reduce the burden on applicants for certification of 
new rotorcraft designs. The proposed changes would reduce or eliminate 
the need for certain special conditions currently required to obtain 
certification of modern rotorcraft. The proposed changes would also 
incorporate the requirements of equivalent level of safety findings 
that the FAA has imposed as conditions for approving certain design 
features.

DATES: Send comments on or before January 30, 2018.

ADDRESSES: Send comments identified by docket number FAA-2017-0990 
using any of the following methods:
     Federal eRulemaking Portal: Go to https://www.regulations.gov and follow the online instructions for sending your 
comments electronically.
     Mail: Send comments to Docket Operations, M-30; U.S. 
Department of Transportation (DOT), 1200 New Jersey Avenue SE., Room 
W12-140, West Building Ground Floor, Washington, DC 20590-0001.
     Hand Delivery or Courier: Take comments to Docket 
Operations in Room W12-140 of the West Building Ground Floor at 1200 
New Jersey Avenue SE., Washington, DC, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
     Fax: Fax comments to Docket Operations at 202-493-2251.
    Privacy: In accordance with 5 U.S.C. 553(c), DOT solicits comments 
from the public to better inform its rulemaking process. DOT posts 
these comments, without edit, including any personal information the 
commenter provides, to www.regulations.gov, as described in the system 
of records notice (DOT/ALL-14 FDMS), which can be reviewed at 
www.dot.gov/privacy.
    Docket: Background documents or comments received may be read at 
https://www.regulations.gov at any time. Follow the online instructions 
for accessing the docket or go to the Docket Operations in Room W12-140 
of the West Building Ground Floor at 1200 New Jersey Avenue SE., 
Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays.

FOR FURTHER INFORMATION CONTACT: For questions concerning this action, 
contact Sandra Shelley, Aviation Safety Engineer, Safety Management 
Group, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone (817) 
222-5110; email [email protected].

SUPPLEMENTARY INFORMATION: 

Authority for This Rulemaking

    The FAA's authority to issue rules on aviation safety is found in 
Title 49 of the United States Code. Subtitle I, Section 106 describes 
the authority of the FAA

[[Page 50584]]

Administrator. Subtitle VII, Aviation Programs, describes in more 
detail the scope of the agency's authority.
    This rulemaking is promulgated under the authority described in 
Subtitle VII, Part A, Subpart III, Sections 44701 and 44704. Under 
section 44701, the FAA is charged with prescribing regulations 
promoting safe flight of civil aircraft in air commerce by prescribing 
minimum standards required in the interest of safety for the design and 
performance of aircraft. Under section 44704, the Administrator issues 
type certificates for aircraft, aircraft engines, propellers, and 
specified appliances when the Administrator finds the product is 
properly designed and manufactured, performs properly, and meets the 
regulations and minimum standards prescribed under section 44701(a). 
This rulemaking is within the scope of these authorities because it 
would promote safety by updating the existing minimum prescribed 
standards used during the type certification process.

I. Overview of Proposed Rule

    The FAA proposes to revise regulations in title 14 Code of Federal 
Regulations (14 CFR) part 27 (Airworthiness Standards: Normal Category 
Rotorcraft) and part 29 (Airworthiness Standards: Transport Category 
Rotorcraft) related to the certification of rotorcraft. The proposed 
changes are necessary due to the extensive application of advancing 
technologies to rotorcraft. Existing airworthiness standards are 
inadequate because they do not address increasing design complexity. To 
address these advances, the FAA currently issues reoccurring special 
conditions, equivalent level of safety findings (ELOS), and means of 
compliance (MOC) issue papers. This proposed rule would address these 
problem areas by updating those standards that cause unnecessary 
burdens in cost and time to both the FAA and the rotorcraft industry. 
Compliance with these proposed regulatory changes would continue to be 
shown by the same testing, analysis, and inspections as in the current 
certification process and there would be a reduced burden through 
clarification of the safety requirements for the installed systems.

II. Background

A. Statement of the Problem

    The FAA is proposing to update parts 27 and 29 because the 
regulations were originally published in 1964 and revisions to the 
airworthiness standards have not kept pace with advances in technology 
for rotorcraft. The FAA addresses the changes to technology by issuing 
reoccurring special conditions, ELOS findings, and MOC issue papers. 
Special conditions are prescribed under 14 CFR 21.16 when the FAA finds 
the applicable airworthiness standards do not contain adequate or 
appropriate safety standards because of a novel or unusual design 
feature. The FAA issues ELOS findings under Sec.  21.21(b)(1) where a 
design does not literally comply with the airworthiness standards, but 
compensating factors exist that provide an equivalent level of safety. 
MOC issue papers document compliance methodologies that fall outside 
existing guidance and policies. These three processes are necessary to 
address new design features for which airworthiness standards are 
lacking, literal compliance with a rule cannot be achieved, or 
alternative methods of compliance are proposed. In some cases, 
advancements in technology have rendered the regulations obsolete.
    These special conditions, ELOS findings, and MOC issue papers 
impact FAA resources and applicants' schedules for obtaining FAA 
approval of their products. By updating the affected standards, many 
special conditions, ELOS findings, and MOC issue papers would be 
unnecessary, thus reducing the burden on both the FAA and industry. We 
also propose to update a few of these rules to correct typographical 
errors.
    Sections 27.1329 and 29.1329 do not adequately address the latest 
technology in flight control automation. These standards adequately 
addressed the functionality of autopilots for many years until recently 
with the development of more sophisticated functions, especially in 
normal category helicopters. The rotorcraft autopilot systems of 
previous years controlled only altitude, attitude, and heading. The 
more advanced autopilot systems also control airspeed, vertical speed, 
and hover. The current rule is inconsistent with FAA-accepted industry 
standards and practices. The current rule does not adequately cover the 
growing changes in the marketplace toward increased automation in the 
primary flight controls.
    Sections 27.1335 and 29.1335 were originally written to address a 
particular flight control concept called ``flight director systems;'' 
however, the term itself has long been considered a standard part of a 
modern autopilot covered under Sec. Sec.  27.1329 and 29.1329. In 
addition, the text we propose to remove from Sec. Sec.  27.1335 and 
29.1335 has been added to the proposed Sec. Sec.  27.1329 and 29.1329 
rules. The impact to industry would be minimal since the current 
material associated with these rules in Advisory Circular (AC) 27-1B, 
Certification of Normal Category Rotorcraft, and AC 29-2C, 
Certification of Transport Category Rotorcraft,\1\ already recognizes 
industry standards and practices.
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    \1\ https://rgl.faa.gov/Regulatory_and_Guidance_Library/.
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    In appendix B to parts 27 and 29, the reference to Amendment 29-14 
in section VIII needs to be removed. By citing the amendment within the 
rule, appendix B requires updating every time a relevant part 27 or 
part 29 rule is changed.

B. National Transportation Safety Board Recommendations

    As a result of incidents involving lithium-ion batteries installed 
on aircraft, the National Transportation Safety Board (NTSB) issued 
Safety Recommendations A-14-032 through 036 to the FAA on May 22, 
2014.\2\ The NTSB recommended the FAA develop abuse tests to simulate 
failures observed in the incidents investigated and to address findings 
in recent research (A-14-032), perform these tests on new aircraft for 
certain installations (A-14-033), develop guidance on acceptable 
methods to induce thermal runaway that reliably simulates battery 
failures (A-14-034), review methods of compliance used to certificate 
in-service lithium-ion battery aircraft installations to ensure that 
they adequately protect against adverse effects of a cell thermal 
runaway (A-14-035), and develop policy to establish a panel of 
technical experts to advise on compliance and best practices for safely 
installing new technology (A-14-036). This proposed rule would 
incorporate these NTSB recommendations as they relate to rotorcraft 
into Sec. Sec.  27.1353 and 29.1353.
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    \2\ https://www.ntsb.gov/.
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III. Discussion of the Proposal

A. AC 27-1B and AC 29-2C Guidance

    AC 27-1B and AC 29-2C provide information on methods of compliance 
with 14 CFR parts 27 and 29, which contain the airworthiness standards 
for normal and transport category rotorcraft. These ACs include methods 
of compliance in the areas of basic design, ground tests, and flight 
tests. With these proposed rules, the FAA is also proposing related 
changes to these ACs.

B. Powerplant Instruments (Sec. Sec.  27.1305 and 29.1305)

    Sections 27.1305 and 29.1305 prescribe the specific required 
powerplant instruments for rotorcraft.

[[Page 50585]]

The current rules specify separate indicators for many of these 
instruments, including engine manifold pressure and engine revolutions 
per minute (r.p.m.) for reciprocating engines, or gas producer speed, 
gas temperature, and torque for turbine engines.
    Traditionally, pilots determine the powerplant performance 
conditions by monitoring individual gauges: Gas temperature, gas 
producer speed, and torque. Sections 27.1305 and 29.1305 establish the 
required powerplant instruments, and Sec. Sec.  27.1321 and 29.1321 
require that these instruments be easily visible to the pilot. These 
instruments measure the performance output of the engines and they 
collectively allow the pilot to continuously monitor the condition and 
health of the engines.
    Many rotorcraft manufacturers have started to incorporate a 
synthesized power indicator (SPI) that provides a single indicator of 
engine performance. This single value displayed to the pilot is 
generally presented as a percentage of the nearest engine limit. The 
continuously displayed SPI presents the calculated value to the flight 
crew on the primary flight displays along with a caption indicating the 
nearest engine limiting parameter that is being used for the SPI 
displayed calculation. Acceptable designs allow the pilot to monitor 
engine performance and trends. Technologies such as an SPI, which 
combine multiple indicators into one, cannot meet the requirements of 
the current rules. By allowing means other than dedicated indicators, 
the proposed changes would permit designs incorporating an SPI or 
similar concepts. The FAA proposes to revise Sec. Sec.  27.1305(e), 
(k), (n), and (o) and 29.1305(a)(5), (11), and (12) to allow other 
means of powerplant indication for these instruments. Section 
27.1305(k) would continue to require a tachometer to indicate main 
rotor speed, but would also require a separate means to indicate the 
r.p.m. of each engine. The FAA also proposes to modify Sec.  27.1305(o) 
by replacing ``turboshaft'' with ``turbine'' to be consistent with 
similar wording used throughout parts 27 and 29.
    For part 29, the FAA proposes to add Sec.  29.1305(b)(4) to permit 
manipulating the powerplant instruments to simulate one engine 
inoperative (OEI) conditions without damaging the engines. Section 
29.1305 requires unbiased engine instrument indications to remain 
available to assure operation within safe limits. Several helicopter 
designs include, for Category A \3\ training purposes (OEI Training 
Mode), a feature to represent a simulated engine failure by reducing 
power of all engines symmetrically. This simulated OEI condition is 
shown on the engine instruments by biasing the engine power, gas 
temperature, and gas producer and free power turbine tachometers on the 
primary flight display. To avoid confusion, the proposed Sec.  
29.1305(b)(4) would require additional annunciations to differentiate 
the simulated OEI condition from that of an actual engine failure.
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    \3\ In 14 CFR 1.1, Category A, with respect to transport 
category rotorcraft, means multiengine rotorcraft designed with 
engine and system isolation features specified in Part 29 and 
utilizing scheduled takeoff and landing operations under a critical 
engine failure concept which assures adequate designated surface 
area and adequate performance capability for continued safe flight 
in the event of engine failure.
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    The proposed changes to Sec.  29.1305 would permit designs 
incorporating an OEI Training Mode. The FAA is not proposing changes to 
Sec.  27.1305 because 14 CFR part 27 Category A rotorcraft are approved 
under appendix C to part 27, which requires compliance with Sec.  
29.1305.

C. Rotorcraft Equipment, Systems, and Installations (Sec. Sec.  
27.1309, 29.1309, and Appendix C to Part 27)

    Sections 27.1309 and 29.1309 apply generally to all systems on the 
aircraft that do not otherwise have specific language to analyze the 
safety aspects of a system. The proposed changes to Sec.  27.1309 would 
address advances in technology and increases in performance of normal 
category rotorcraft that were not envisioned when this rule was 
originally promulgated. Manufacturers installed complex and highly 
integrated systems in part 27 rotorcraft certificated for instrument 
flight rules (IFR) under appendix B and Category A operations under 
appendix C. At that time, the FAA did not envision complex and highly 
integrated systems would be installed in non-IFR and non-Category A 
normal category rotorcraft because industry was not employing this 
advanced technology or the technology did not exist. The analysis 
methods used to identify and determine the effects of system failures 
required in Sec.  27.1309 are not adequate for today's complex and 
highly integrated systems. The use of this advanced technology resulted 
in an exponential increase in the number of ways rotorcraft systems can 
fail and a decrease in the discernibility of such failures. To ensure 
the reliability of the rotorcraft system is not compromised when 
utilizing complex and highly integrated technology, the FAA is 
proposing a more structured repeatable failure analysis.
    The proposed change would also eliminate the distinction between 
single-engine and multi-engine rotorcraft. Section 27.1309 currently 
requires applicants to assess the effects of failures that may be 
introduced by installed systems and equipment, and distinguishes that 
the methods for assessing these failures may be different between 
single and multi-engine rotorcraft. This distinction was envisioned 
because multi-engine rotorcraft employed complex systems or systems 
with more severe failure effects. This distinction is now irrelevant 
since current analysis tools for technologies and associated failure 
effects do not consider number of engines as required input.
    The proposed rule would clarify the requirement to perform a proper 
failure analysis and also recognize that the severity of failures can 
vary. Since the current rule was promulgated, the number of failure 
condition categories has varied. Current industry standards and 
practices recognize five failure condition categories: Catastrophic, 
Hazardous, Major, Minor, and No-Safety Effect. The proposed rule 
recognizes the maximum and minimum failure effects without prescribing 
the number of failure effect severity categories. This proposed change 
would also accommodate future changes in industry failure analysis 
techniques and reflect current certification practices. Additionally, 
it would eliminate the need to issue recurring special conditions and 
remove the additional time and cost to industry.
    The changes proposed for Sec. Sec.  27.1309 and 29.1309 would make 
the sections consistent. These changes would remove the necessity to 
reference Sec.  29.1309 in appendix C of part 27. Although a specific 
reference to Sec.  27.1309 would not be added, appendix C of part 27 
already requires compliance with all of part 27 for Category A 
certification. These proposed changes would not eliminate the 
requirement to reassess compliance with Sec.  27.1309 for applicants 
who request Category A operations. The FAA proposes to change appendix 
C to delete the reference to Sec.  29.1309.
    The FAA proposes to update Sec.  29.1309 to be consistent with 
industry standards and practices for conducting failure analysis. These 
proposed changes are intended to allow flexibility in the types of 
assessments applicants may provide for showing compliance.

[[Page 50586]]

    Section 29.1309 currently requires applicants to assess the effects 
of failures resulting from installed systems and equipment. The current 
rule also identifies differences in the depth of assessing failures 
between Category A and Category B \4\ rotorcraft. Complex and highly 
integrated systems were typically installed in part 29 rotorcraft 
certificated for Category A operations. Like the distinction between 
single-engine and multi-engine rotorcraft discussed previously, this 
distinction was made because the FAA did not envision that complex and 
highly integrated systems would be installed in rotorcraft certificated 
for Category B operations. This distinction is now irrelevant since 
current analysis tools for technologies and associated failure effects 
do not differ between Category A and Category B. The FAA proposes to 
add an introductory paragraph and revise paragraphs (a) and (b) to 
clarify that all equipment, systems, and installations on the 
rotorcraft must be analyzed and to remove the distinction between 
Category A and B. Although the effects of the failures may be 
different, the method for conducting the failure analysis is the same 
regardless of the operations evaluated.
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    \4\ In 14 CFR 1.1, Category B, with respect to transport 
category rotorcraft, means single-engine or multiengine rotorcraft 
which do not fully meet all Category A standards. Category B 
rotorcraft have no guaranteed stay-up ability in the event of engine 
failure and unscheduled landing is assumed.
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    The term ``warning'' in Sec.  29.1309(c) and (d) has been 
interpreted as requiring a red level alert, when the intent was to 
notify the crew of all required annunciations. Therefore, the FAA 
proposes to modify paragraphs (c) and (d) by removing the terms 
``warning'' and ``probability'' and replacing them with 
``annunciation'' and ``effect'' respectively, and adding ``misleading 
data'' as a standard failure mode.
    The FAA also proposes removing the requirements of Sec.  29.1309(e) 
and (f) dealing specifically with electrical systems as they are 
covered by Sec. Sec.  29.1351, 29.1353, 29.1355, and 29.1357.

D. Automatic Flight Guidance and Control Systems (Sec. Sec.  27.1329, 
27.1335, 29.1329, and 29.1335)

    The FAA proposes to standardize terminology and combine the 
requirements for automatic pilot and flight director systems into one 
rule. Sections 27.1329 and 29.1329 address automatic pilot systems 
while Sec. Sec.  27.1335 and 29.1335 address flight director systems. 
At the time these rules were promulgated, the functionality of designs 
prompted a separate rule for each system. Since then, systems for 
automatic control of flight have evolved. Modern designs include both 
automatic pilot and flight director systems and are now referred to as 
automatic flight guidance and control systems. Having these systems in 
separate rules that use different terminology has resulted in some 
confusion. The proposed changes would remove Sec. Sec.  27.1335 and 
29.1335 and incorporate the requirements into Sec. Sec.  27.1329 and 
29.1329. The FAA also proposes to use the term ``automatic flight 
guidance and control systems'' to address both automatic pilot and 
flight director systems, as well as the components.

E. Instrument Systems (Sec.  29.1333 and Appendix B to Parts 27 and 29)

    Currently, Sec.  29.1333(a) requires isolating the pilot instrument 
system from any other operating systems. At the time the rule was 
promulgated, these systems were federated, and connecting these systems 
increased the likelihood that a fault in one system would cause a fault 
in the pilot instrument system. This physical independence between the 
pilot system and other operating systems prevented the pilot system's 
reliability from being compromised by other operating systems. With the 
adoption of microprocessor technology and the trend towards complex and 
highly integrated systems, the requirement for physical independence is 
no longer appropriate. The use of this technology resulted in an 
exponential increase in the number of ways rotorcraft systems can fail 
and a decrease in the discernibility of such failures. To ensure the 
reliability of the pilot system is not compromised when utilizing 
microprocessors or highly integrated systems, modern designs allow 
redundant systems in the rotorcraft to compare information. Rotorcraft 
cannot utilize current technology, and redundant systems cannot compare 
information, when the pilot instrument system is isolated.
    The FAA proposes to revise Sec.  29.1333(a) and section 
VIII(b)(5)(i) of appendix B to parts 27 and 29 to make them applicable 
only to pneumatic systems. These proposed changes would allow for the 
use of modern technology to monitor and display highly integrated 
information regarding the rotorcraft that is currently not permitted. 
The FAA also proposes revising appendix B to parts 27 and 29 to remove 
the amendment level as previously discussed in section B of the 
preamble.

F. Electrical Systems and Equipment (Sec.  29.1351) and Energy Storage 
Systems (Sec. Sec.  27.1353 and 29.1353)

    The FAA proposes changing Sec. Sec.  27.1353 and 29.1353 to provide 
a general regulation that is not directed at a particular battery or 
battery chemistry. The existing regulations were first written when 
backup electrical power was provided solely by a lead acid battery. The 
regulations were later amended to add requirements specific to the 
nickel-cadmium battery chemistry. Recently, batteries have been 
developed using various lithium chemistries. Lead acid, nickel-cadmium, 
and lithium batteries are all energy storage devices with different 
operational parameters and failure mechanisms. Rather than add specific 
lithium battery requirements, which would necessitate further 
amendments to address future energy storage chemistries, the FAA is 
proposing to generalize the regulation to accommodate any energy 
storage system. The proposed regulation would be less prescriptive than 
the existing regulation.
    The FAA's intent with this proposal is that the modified regulation 
would be directly applicable to both lead acid and nickel-cadmium 
batteries without imposing additional requirements. In addition, this 
generalized approach would allow the FAA to consider batteries, fuel 
cells, or any other energy storage device not yet developed. Certain 
attributes tied to a specific battery chemistry currently found in the 
regulation would be addressed in AC 27-1B and AC 29-2C. These proposed 
changes to Sec. Sec.  27.1353 and 29.1353 are intended to reduce the 
burden on the FAA and the rotorcraft industry associated with issuing 
special conditions and the related issue papers.
    Section 29.1353, paragraphs (a) and (b) would be moved into Sec.  
29.1351 as paragraphs (e) and (f) respectively. These paragraphs are 
general requirements for all electrical systems and equipment 
installations. This change is proposed for consistency because those 
requirements are more appropriate in Sec.  29.1351. This proposed 
change would standardize the requirements of Sec. Sec.  27.1353 and 
29.1353 and both section titles would be changed to ``Energy storage 
systems'' to properly reflect the new language.

G. Instrument Markings (Sec. Sec.  27.1545, 29.1545, 27.1549, and 
29.1549)

    The FAA proposes to modify Sec. Sec.  27.1545(b)(4), 27.1549(b), 
29.1545(b)(4), and 29.1549(b) by eliminating the restriction of only 
using

[[Page 50587]]

a ``green arc'' to indicate normal operating ranges. The existing rules 
require using a green arc for normal operating ranges on airspeed and 
powerplant instruments. Modern glass cockpits generally do not contain 
these green indicators. The philosophy utilized by modern cockpit 
designs is the ``dark, quiet cockpit,'' and only yellow or red is 
presented to indicate the aircraft is outside the normal or safe 
operating range. The absence of green arcs did not meet the requirement 
of the rule. Since the rule was promulgated, the FAA has determined 
that if all abnormal conditions are otherwise adequately indicated, 
green markings are unnecessary. These accepted design features include 
the pilot being able to easily interpret (by way of glancing at the 
instrument) whether a parameter is in a precautionary range (yellow) or 
beyond a limit (red). Almost every current rotorcraft design now 
incorporates a glass cockpit that requires an ELOS finding for the 
absence of green arcs. This proposal only affects the color utilized 
for the normal operating ranges and does not address graduation 
markings on an instrument.
    The FAA also proposes to remove the term ``radial'' from Sec. Sec.  
27.1545(b)(1), 27.1549(a), 29.1545(b)(1), and 29.1549(a). At the time 
these rules were promulgated, cockpit instruments were circular, and 
therefore the technically-correct term ``radial line'' was used. 
Technological advances have since produced linear-scale gauges 
rendering the term ``radial'' obsolete. The term ``line'' is intended 
to represent a radial for round instruments or a line for tape or other 
style instruments.
    The FAA further proposes to replace ``arc'' with ``range'' in 
Sec. Sec.  27.1545(b)(3), 27.1545(b)(4), 27.1549(b), 27.1549(c), 
27.1549(d), 29.1545(b)(3), 29.1545(b)(4), 29.1549(b), 29.1549(c), and 
29.1549(d). When these regulations were created, cockpit instruments 
were circular. ``Arc'' is a term that only applies to round gauges and 
not to tape or other style instruments, which are in popular use today. 
The FAA intends ``range'' to be applied to round, tape, or other style 
instruments.
    Finally, the FAA proposes to move the requirement for indicating 
VNE (power-off) from Sec.  27.1545(b)(2) to Sec.  
27.1545(b)(1)(iii) and modify it to encompass designs that incorporate 
a means other than a red cross-hatched line. The FAA has previously 
accepted designs that utilize a single red line for VNE 
(power-on) and VNE (power-off) when not concurrently 
displayed. Additionally, a red and white cross-hatched ``barber pole'' 
may not be the only acceptable method for distinguishing VNE 
(power-off) from VNE (power-on). The FAA also proposes to 
apply this change to Sec.  29.1545.

H. Control Markings (Sec. Sec.  27.1555 and 29.1555)

    The FAA proposes to modify Sec. Sec.  27.1555(c)(1) and 
29.1555(c)(1) to permit more than one method to inform the pilot of the 
usable fuel system capacity. The existing rules require marking the 
usable fuel capacity at the fuel quantity indicator. Older, analog fuel 
gauges (many without numbers) used a placard to inform the pilot of the 
useful fuel quantity. With modern display systems, the location of the 
fuel quantity indicator, as well as the fact that the location may 
change, make it impractical to affix a placard next to the display. In 
addition, although useful fuel capacity is commonly included in the 
rotorcraft flight manual, the proposed alternate method would make this 
a requirement to address the lack of continuous display provided by a 
placard.

I. Typographical and Standardizing Corrections (Sec. Sec.  27.87, 
27.903, 29.955, 29.977, 29.1019, 29.1517, and 29.1587)

    The FAA proposes to correct several typographical errors and to 
revise certain terminology differences between part 27 and part 29. 
First, the FAA proposes to revise the title of Sec.  27.87 to coincide 
with the title of Sec.  29.87, which is the equivalent transport 
category rotorcraft requirement. The title of Sec.  29.87 was changed 
from ``Limiting height-speed envelope'' to ``Height-velocity envelope'' 
in order to ``agree with the commonly used term.'' However, the 
corresponding title to Sec.  27.87 was not similarly changed at that 
time.
    The FAA also proposes to replace the term ``height-speed'' with the 
term ``height-velocity'' throughout Sec. Sec.  27.1587, 29.1587, and 
29.1517 to be consistent with the title nomenclature of Sec. Sec.  
27.87 and 29.87. These proposed changes are intended to reduce 
confusion between and within parts 27 and 29.
    The FAA also proposes to reformat Sec.  27.903(d) so that it is 
consistent with the format of the Sec.  29.903(e) engine restart 
capability requirement. When the Sec.  27.903(d) restart capability 
requirements were adopted, the paragraph structure of the existing 
Sec.  29.903(e) was not used even though the technical requirements 
were intended to be identical. The restart capability requirements of 
Sec.  27.903(d) are not being changed in this proposal. These proposed 
changes are intended to reduce confusion between part 27 and part 29 by 
using a standard format for the same technical requirements.
    The FAA proposes to correct a typographical error in Sec. Sec.  
29.955 and 29.1019. When Sec.  29.1305 was updated to add a requirement 
for an oil pressure indicator for pressure-lubricated gearboxes, the 
numbering sequence was changed when the additional requirement was 
inserted at paragraph (a)(6). The Sec.  29.1305(a)(17) fuel filter 
contamination warning was moved to paragraph (a)(18), and the Sec.  
29.1305(a)(18) turbine engine filter contamination warning was moved to 
paragraph (a)(19). However, the reference to the fuel filter 
contamination warning in Sec.  29.955(a)(7) and the turbine engine 
filter contamination warning in Sec.  29.1019(a)(5) were not updated to 
account for the change in numbering sequence. This proposed change 
would correct the reference at Sec. Sec.  29.955(a)(7) and 
29.1019(a)(5).
    Finally, the FAA proposes to correct a typographical error in Sec.  
29.977. When Sec.  29.977 was updated, it incorrectly carried over 
references to ``airplanes'' from an identical part 23 update. The 
proposed change would revise Sec.  29.977 by removing the term 
``airplanes'' and replacing it with the term ``rotorcraft.''

IV. Regulatory Notices and Analyses

A. Regulatory Evaluation

    Changes to Federal regulations must undergo several economic 
analyses. First, Executive Order 12866 and Executive Order 13563 direct 
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 (Pub. 
L. 96-354) requires agencies to analyze the economic impact of 
regulatory changes on small entities. Third, the Trade Agreements Act 
(Pub. L. 96-39) prohibits agencies from setting standards that create 
unnecessary obstacles to the foreign commerce of the United States. In 
developing U.S. standards, the Trade Act requires agencies to consider 
international standards and, where appropriate, that they be the basis 
of U.S. standards. 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 with 
base year of 1995).

[[Page 50588]]

This portion of the preamble summarizes the FAA's analysis of the 
economic impacts of this proposed rule.
    Department of Transportation Order DOT 2100.5 prescribes policies 
and procedures for simplification, analysis, and review of regulations. 
If the expected cost impact is so minimal that a proposed or final rule 
does not warrant a full evaluation, this order permits that a statement 
to that effect and the basis for it to be included in the preamble if a 
full regulatory evaluation of the cost and benefits is not prepared. 
Such a determination has been made for this proposed rule. The 
reasoning for this determination follows:
    The FAA proposes to revise regulations in 14 CFR part 27 
(Airworthiness Standards: Normal Category Rotorcraft) and part 29 
(Airworthiness Standards: Transport Category Rotorcraft) related to the 
certification of rotorcraft. The proposed changes are necessary due to 
advancing technologies, which address a lack of adequate airworthiness 
standards resulting from increasing design complexity. As a result, 
many regulatory sections are subject to reoccurring special conditions, 
ELOS, and MOC issue papers. This proposed rulemaking would address 
these problem areas by updating the rules that cause unnecessary 
burdens in cost and time to both the FAA and the rotorcraft industry. 
The compliance cost to industry of these proposed regulation changes 
would be minimal. The justification for minimal cost by regulation is 
identified in sections 1 through 9 below.
1. Powerplant Instruments (Sec. Sec.  27.1305 and 29.1305)
    Changes to this section would allow for other means of compliance 
for powerplant instrument indicators. Other means of compliance are 
voluntary and do not impose any new cost but could be cost relieving 
for those that choose to voluntarily comply. Additionally, for Sec.  
29.1305, the FAA would permit manipulating the powerplant instruments 
to simulate OEI conditions without damaging the engines. However, 
helicopters with OEI Training Mode would require additional indicators 
to differentiate the OEI condition from actual engine failure, but 
these indicators are already being installed in current rotorcraft. The 
FAA believes this proposed change would impose minimal new cost to 
industry, as these are current industry practice.
2. Normal Category Rotorcraft Equipment, Systems, and Installations 
(Sec.  27.1309 and Appendix C to Part 27)
    The FAA clarifies the requirement to perform proper failure 
analysis that would adopt the current industry practice of five failure 
category conditions. Additionally, the FAA eliminates the distinction 
between single-engine and multi-engine rotorcraft as this distinction 
is irrelevant because current analysis tools for technologies and 
associated failure effects no longer consider the number of engines. As 
these are current industry practice, the FAA asserts that the cost 
associated with these changes is minimal.
3. Transport Category Rotorcraft Equipment, Systems, and Installation 
(Sec.  29.1309)
    This section would be updated to be consistent with industry 
standards and practices for conducting failure analysis. The proposed 
rule would clarify the requirement to perform a proper failure analysis 
and also recognize that the severity of failures can vary. The FAA 
asserts that performing a proper failure analysis would be minimal cost 
as it would codify current industry practices. Additionally, this 
section would be changed to accommodate future changes in industry 
failure analysis techniques and reflects current certification 
practices. Moving to a performance based standard would reduce the need 
to issue recurring special conditions and potentially save manufactures 
that choose to use an alternative means of compliance. Thus, these 
proposed changes would impose minimal cost.
4. Automatic Flight Guidance and Control Systems (Sec. Sec.  27.1329, 
27.1335, 29.1329, and 29.1335)
    The FAA proposes to standardize terminology and combine the 
requirements for automatic pilot and flight director systems into one 
rule. Modern designs include both automatic pilot and flight director 
systems and are now referred to as automatic flight guidance and 
control systems. Changes to this section would match current industry 
practices at a minimal cost.
5. Instrument Systems (Sec.  29.1333 and Appendix B to Parts 27 and 29)
    The FAA proposed change would allow for the use of more modern 
integrated systems to monitor and display highly integrated information 
regarding the rotorcraft. This section would impose minimal cost as the 
updates reflect modern industry practices of integrating instrument 
systems.
6. Electrical Systems and Equipment (Sec.  29.1351) and Energy Storage 
Systems (Sec. Sec.  27.1353 and 29.1353)
    The FAA proposed changes are less prescriptive and performance-
based to accommodate different energy storage systems. The modified 
regulation would be directly applicable to both lead acid and nickel-
cadmium batteries without imposing additional requirements. The change 
would allow the FAA to keep up with changes in technology. Cost to the 
industry should be minimal as performance based requirements allow for 
minimal cost options to meet the current standard.
7. Instrument Markings (Sec. Sec.  27.1545, 29.1545, 27.1549, and 
29.1549)
    The proposed rule would remove the restrictive requirement for some 
instrument markings to allow alternative means of compliance, i.e.--
green arc, radial red line, etc. Allowing for another means of 
compliance is voluntary and would be either a minimal cost and possibly 
cost relieving for manufactures that elect to outfit the rotorcraft 
with different instrument markings.
8. Control Markings (Sec. Sec.  27.1555 and 29.1555)
    The proposed rule would permit more than one method to inform the 
pilot of the usable fuel system capacity. However, alternative method 
must address the lack of continuous display. Changes to this section 
allows for more than one means of compliance. Offering alternative 
means of compliance allows industry to meet the requirement with the 
least costly option that can be cost relieving or the existing method 
of compliance, but either method would be no more than minimal cost.
9. Typographical and Standardizing Corrections (Sec. Sec.  27.87, 
27.903, 29.955, 29.977, 29.1019, 29.1517, and 29.1587)
    Costs for proposed changes to this section are minimal as these are 
strictly typographical or standardizing corrections.
    The FAA has, therefore, determined that this proposed rule is not a 
``significant regulatory action'' as defined in section 3(f) of 
Executive Order 12866, and is not ``significant'' as defined in DOT's 
Regulatory Policies and Procedures. The FAA requests comments with 
supporting justification about the FAA determination of minimal cost 
impact.

B. Regulatory Flexibility Determination

    The Regulatory Flexibility Act of 1980 (Pub. L. 96-354) (RFA) 
establishes ``as a principle of regulatory issuance that

[[Page 50589]]

agencies shall endeavor, consistent with the objectives of the rule and 
of applicable statutes, to fit regulatory and informational 
requirements to the scale of the businesses, organizations, and 
governmental jurisdictions subject to regulation. To achieve this 
principle, agencies are required to solicit and consider flexible 
regulatory proposals and to explain the rationale for their actions to 
assure that such proposals are given serious consideration.'' The RFA 
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 rule will 
have a significant economic impact on a substantial number of small 
entities. If the agency determines that it will, the agency must 
prepare a regulatory flexibility analysis as described in the RFA. 
However, if an agency determines that a rule is not expected to have a 
significant economic impact on a substantial number of small entities, 
section 605(b) of the RFA provides that the head of the agency may so 
certify and a regulatory flexibility analysis is not required. The 
certification must include a statement providing the factual basis for 
this determination, and the reasoning should be clear.
    The FAA proposes to amend the certification standards of normal and 
transport category helicopters. The proposed changes reflect modern 
designs currently used in the rotorcraft industry and would reduce the 
burden on applicants for certification of new rotorcraft designs. The 
proposed changes would reduce or eliminate the need for certain special 
conditions currently required to obtain certification of modern 
rotorcraft. This proposed rule would merely revise and clarify FAA 
rulemaking procedures; the expected outcome will have only a minimal 
cost impact on any small entity affected by this rulemaking action.
    If an agency determines that a rulemaking will not result in a 
significant economic impact on a substantial number of small entities, 
the head of the agency may so certify under section 605(b) of the RFA. 
Therefore, as provided in section 605(b), the head of the FAA certifies 
that this rulemaking will not result in a significant economic impact 
on a substantial number of small entities.

C. International Trade Impact Assessment

    The Trade Agreements Act of 1979 (Pub. L. 96-39), as amended by the 
Uruguay Round Agreements Act (Pub. L. 103-465), prohibits Federal 
agencies from establishing standards or engaging in related activities 
that create unnecessary obstacles to the foreign commerce of the United 
States. Pursuant to these Acts, the establishment of standards is not 
considered an unnecessary obstacle to the foreign commerce of the 
United States, so long as the standard has a legitimate domestic 
objective, such as the protection of safety, and does not operate in a 
manner that excludes imports that meet this objective. The statute also 
requires consideration of international standards and, where 
appropriate, that they be the basis for U.S. standards. The FAA has 
assessed the potential effect of this proposed rule and determined that 
the potential benefits are available to both domestic and international 
firms which would either have no affect or a positive effect on 
international trade.

D. Unfunded Mandates Assessment

    Title II of the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-
4) requires each Federal agency to prepare a written statement 
assessing the effects of any Federal mandate in a proposed or final 
agency rule that may result in an expenditure of $100 million or more 
(in 1995 dollars) in any one year by State, local, and tribal 
governments, in the aggregate, or by the private sector; such a mandate 
is deemed to be a ``significant regulatory action.'' The FAA currently 
uses an inflation-adjusted value of $155 million in lieu of $100 
million. This proposed rule does not contain such a mandate; therefore, 
the requirements of Title II of the Act do not apply.

E. Paperwork Reduction Act

    The Paperwork Reduction Act of 1995 (44 U.S.C. 3507(d)) requires 
that the FAA consider the impact of paperwork and other information 
collection burdens imposed on the public. The FAA has determined that 
there would be no new requirement for information collection associated 
with this proposed rule.

F. International Compatibility and Cooperation

    In keeping with U.S. obligations under the Convention on 
International Civil Aviation, it is FAA policy to conform to 
International Civil Aviation Organization (ICAO) Standards and 
Recommended Practices to the maximum extent practicable. The FAA has 
determined that there are no ICAO Standards and Recommended Practices 
that correspond to these proposed regulations.

G. Environmental Analysis

    FAA Order 1050.1F identifies FAA actions that are categorically 
excluded from preparation of an environmental assessment or 
environmental impact statement under the National Environmental Policy 
Act in the absence of extraordinary circumstances. The FAA has 
determined this rulemaking action qualifies for the categorical 
exclusion identified in paragraph 5-6.6.f and involves no extraordinary 
circumstances.

V. Executive Order Determinations

A. Executive Order 13132, Federalism

    The FAA has analyzed this proposed rule under the principles and 
criteria of Executive Order 13132, Federalism. The agency has 
determined that this action would not have a substantial direct effect 
on the States, or the relationship between the Federal Government and 
the States, or on the distribution of power and responsibilities among 
the various levels of government, and, therefore, would not have 
Federalism implications.

B. Executive Order 13211, Regulations That Significantly Affect Energy 
Supply, Distribution, or Use

    The FAA analyzed this proposed rule under Executive Order 13211, 
Actions Concerning Regulations that Significantly Affect Energy Supply, 
Distribution, or Use (May 18, 2001). The agency has determined that it 
would not be a ``significant energy action'' under the executive order 
and would not be likely to have a significant adverse effect on the 
supply, distribution, or use of energy.

VI. Additional Information

A. Comments Invited

    The FAA invites interested persons to participate in this 
rulemaking by submitting written comments, data, or views. The agency 
also invites comments relating to the economic, environmental, energy, 
or federalism impacts that might result from adopting the proposals in 
this document. The most helpful comments reference a specific portion 
of the proposal, explain the reason for any recommended change, and 
include supporting data. To ensure the docket does not contain 
duplicate comments, commenters should send only one copy of written 
comments, or if comments are filed electronically, commenters should 
submit only one time.
    The FAA will file in the docket all comments it receives, as well 
as a report summarizing each substantive public contact with FAA 
personnel concerning

[[Page 50590]]

this proposed rulemaking. Before acting on this proposal, the FAA will 
consider all comments it receives on or before the closing date for 
comments. The FAA will consider comments filed after the comment period 
has closed if it is possible to do so without incurring expense or 
delay. The agency may change this proposal in light of the comments it 
receives.
    Proprietary or Confidential Business Information: Commenters should 
not file proprietary or confidential business information in the 
docket. Such information must be sent or delivered directly to the 
person identified in the FOR FURTHER INFORMATION CONTACT section of 
this document, and marked as proprietary or confidential. If submitting 
information on a disk or CD ROM, mark the outside of the disk or CD 
ROM, and identify electronically within the disk or CD ROM the specific 
information that is proprietary or confidential.
    Under 14 CFR 11.35(b), if the FAA is aware of proprietary 
information filed with a comment, the agency does not place it in the 
docket. It is held in a separate file to which the public does not have 
access, and the FAA places a note in the docket that it has received 
it. If the FAA receives a request to examine or copy this information, 
it treats it as any other request under the Freedom of Information Act 
(5 U.S.C. 552). The FAA processes such a request under Department of 
Transportation procedures found in 49 CFR part 7.

B. Availability of Rulemaking Documents

    An electronic copy of rulemaking documents may be obtained from the 
Internet by--
    1. Searching the Federal eRulemaking Portal (https://www.regulations.gov);
    2. Visiting the FAA's Regulations and Policies Web page at https://www.faa.gov/regulations_policies or
    3. Accessing the Government Printing Office's Web page at https://www.gpo.gov/fdsys/.
    Copies may also be obtained by sending a request to the Federal 
Aviation Administration, Office of Rulemaking, ARM-1, 800 Independence 
Avenue SW., Washington, DC 20591, or by calling (202) 267-9680. 
Commenters must identify the docket number of this rulemaking.
    All documents the FAA considered in developing this proposed rule, 
including economic analyses and technical reports, may be accessed from 
the Internet through the Federal eRulemaking Portal referenced in item 
(1) above.

List of Subjects

14 CFR Part 27

    Aircraft, Aviation safety.

14 CFR Part 29

    Aircraft, Aviation safety.

The Proposed Amendment

    In consideration of the foregoing, the Federal Aviation 
Administration proposes to amend chapter I of title 14, Code of Federal 
Regulations as follows:

PART 27--AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT

0
1. The authority citation for part 27 continues to read as follows:

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

0
2. Amend Sec.  27.87 by revising the section heading and paragraph (a) 
introductory text to read as follows:


Sec.  27.87  Height-velocity envelope.

    (a) If there is any combination of height and forward speed 
(including hover) under which a safe landing cannot be made under the 
applicable power failure condition in paragraph (b) of this section, a 
limiting height-velocity envelope must be established (including all 
pertinent information) for that condition, throughout the ranges of--
* * * * *
0
3. Amend Sec.  27.903 by revising paragraph (d) to read as follows:


Sec.  27.903  Engines.

* * * * *
    (d) Restart capability. (1) A means to restart any engine in flight 
must be provided.
    (2) Except for the in-flight shutdown of all engines, engine 
restart capability must be demonstrated throughout a flight envelope 
for the rotorcraft.
    (3) Following the in-flight shutdown of all engines, in-flight 
engine restart capability must be provided.
0
4. Amend Sec.  27.1305 by revising paragraphs (e), (k) introductory 
text, (n), and (o) to read as follows:


Sec.  27.1305  Powerplant instruments.

* * * * *
    (e) A means to indicate manifold pressure for each altitude engine.
* * * * *
    (k) A means to indicate the r.p.m. of each engine and at least one 
tachometer, as applicable, for:
* * * * *
    (n) A means to indicate the gas temperature for each turbine 
engine.
    (o) A means to enable the pilot to determine the torque of each 
turbine engine, if a torque limitation is established for that engine 
under Sec.  27.1521(e).
* * * * *
0
5. Revise Sec.  27.1309 to read as follows:


Sec.  27.1309  Equipment, systems, and installations.

    The equipment, systems, and installations whose functioning is 
required by this subchapter must be designed and installed to ensure 
that they perform 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 requirements also apply:
    (a) The design of each item of equipment, system, and installation 
must be analyzed separately and in relation to other rotorcraft systems 
and installations 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 operating conditions.
    (b) Each item of equipment, system, and installation must be 
designed and installed so that:
    (1) The occurrence of any catastrophic failure condition is 
extremely improbable;
    (2) The occurrence of any minor failure condition is no more than 
probable; and
    (3) For the occurrence of any other failure condition, the 
probability of the failure condition must be inversely proportional to 
its consequences.
    (c) A means to alert the crew in the event of a failure must be 
provided when an unsafe system operating condition exists to enable 
them to take corrective action. Systems, controls, and associated 
monitoring and crew alerting means must be designed to minimize crew 
errors that could create additional hazards.
    (d) Compliance with the requirements 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, including malfunctions and 
misleading data and input from external sources;
    (2) The effect of multiple failures and latent failures;
    (3) The resulting effects on the rotorcraft and occupants, 
considering the stage of flight and operating conditions; and
    (4) The crew warning cues and the corrective action required.
0
6. Amend Sec.  27.1329 by revising the section heading, adding 
introductory

[[Page 50591]]

text, and revising paragraphs (a), (d), and (e) to read as follows:


Sec.  27.1329  Automatic flight guidance and control system.

    For the purpose of this subpart, an automatic flight guidance and 
control system may consist of an autopilot, flight director, or a 
component that interacts with stability augmentation or trim.
    (a) Each automatic flight guidance and control system must be 
designed so that it:
    (1) Can be overpowered by the pilot to allow control of the 
rotorcraft;
    (2) Provides a means to disengage the system by the pilot to 
prevent it from interfering with the control of the rotorcraft; and
    (3) Provides a means to indicate to the flight crew its current 
mode of operation.
    Selector switch position is not acceptable as a means of 
indication.
* * * * *
    (d) The system must be designed so that, within the range of 
adjustment available to the pilot, it cannot produce hazardous loads on 
the rotorcraft, or create hazardous deviations in the flight path, 
under any flight condition appropriate to its use or in the event of a 
malfunction.
    (e) If the automatic flight guidance and control system integrates 
signals from auxiliary controls or furnishes signals for operation of 
other equipment, there must be a means to prevent improper operation.
* * * * *


Sec.  27.1335  [Removed]

0
7. Remove Sec.  27.1335.
0
8. Revise Sec.  27.1353 to read as follows:


Sec.  27.1353  Energy storage systems.

    Energy storage systems must be designed and installed as follows:
    (a) Energy storage systems must provide automatic protective 
features for any conditions that could prevent continued safe flight 
and landing.
    (b) Energy storage systems must not emit any explosive or toxic 
gases, smoke, or fluids except through designed venting provisions and 
must not accumulate in hazardous quantities within the rotorcraft.
    (c) Corrosive fluids or gases that escape from the system must not 
damage surrounding structures, adjacent equipment, or systems necessary 
for continued safe flight and landing.
    (d) The maximum amount of heat that can be generated during any 
operation or under any failure condition of the energy storage system 
or its individual components must not result in any hazardous effect on 
rotorcraft structure, equipment, or systems necessary for continued 
safe flight and landing.
    (e) Energy storage system installations required for continued safe 
flight and landing of the rotorcraft must have monitoring features and 
a means to indicate to the pilot the status of all critical system 
parameters.
0
9. Amend Sec.  27.1545 by revising paragraph (b) to read as follows:


Sec.  27.1545  Airspeed indicator.

* * * * *
    (b) The following markings must be made:
    (1) A red line--
    (i) For rotorcraft other than helicopters, at VNE.
    (ii) For helicopters, at VNE (power-on).
    (iii) For helicopters, at VNE (power-off). If 
VNE (power-off) is less than VNE (power-on) and 
both are simultaneously displayed, the red line at VNE 
(power-off) must be clearly distinguishable from the red line at 
VNE (power-on).
    (2) [Reserved]
    (3) For the caution range, a yellow range.
    (4) For the normal operating range, a green or unmarked range.
* * * * *
0
10. Amend Sec.  27.1549 by revising paragraphs (a) through (d) to read 
as follows:


Sec.  27.1549  Powerplant instruments.

* * * * *
    (a) Each maximum and, if applicable, minimum safe operating limit 
must be marked with a red line;
    (b) Each normal operating range must be marked as a green or 
unmarked range;
    (c) Each takeoff and precautionary range must be marked with a 
yellow range or yellow line; and
    (d) Each engine or propeller range that is restricted because of 
excessive vibration stresses must be marked with red ranges or red 
lines.
* * * * *
0
11. Amend Sec.  27.1555 by revising paragraph (c)(1) to read as 
follows:


Sec.  27.1555  Control markings.

* * * * *
    (c) * * *
    (1) For fuel systems having no selector controls, the usable fuel 
capacity of the system must be indicated at the fuel quantity indicator 
unless it is:
    (i) Provided by another system or equipment readily accessible to 
the pilot; and
    (ii) Contained in the limitations section of the rotorcraft flight 
manual.
* * * * *
0
12. Amend Sec.  27.1587 by revising paragraph (a)(1) to read as 
follows:


Sec.  27.1587  Performance information.

    (a) * * *
    (1) Enough information to determine the limiting height-velocity 
envelope.
* * * * *
0
13. Amend appendix B to part 27 by revising paragraphs VIII 
introductory text and VIII(b)(5)(i) to read as follows:

Appendix B to Part 27--Airworthiness Criteria for Helicopter Instrument 
Flight

* * * * *
    VIII. Equipment, systems, and installation. The basic equipment and 
installation must comply with Sec. Sec.  29.1303, 29.1431, and 29.1433, 
with the following exceptions and additions:
* * * * *
    (b) * * *
    (5) * * *
    (i) For pneumatic systems, only the required flight instruments for 
the first pilot may be connected to that operating system;
* * * * *

Appendix C to Part 27 [Amended]

0
14. In appendix C to part 27, amend paragraph C27.2 by removing the 
entry ``29.1309(b)(2) (i) and (d)-Equipment, systems, and 
installations.''

PART 29--AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT

0
15. The authority citation for part 29 continues to read as follows:

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

0
16. Amend Sec.  29.955 by revising paragraph (a)(7) to read as follows:


Sec.  29.955  Fuel flow.

    (a) * * *
    (7) The fuel filter required by Sec.  29.997 is blocked to the 
degree necessary to simulate the accumulation of fuel contamination 
required to activate the indicator required by Sec.  29.1305(a)(18).
* * * * *
0
17. Amend Sec.  29.977 by revising paragraphs (a)(1) and (2) to read as 
follows:


Sec.  29.977  Fuel tank outlet.

    (a) * * *
    (1) For reciprocating engine powered rotorcraft, have 8 to 16 
meshes per inch; and
    (2) For turbine engine powered rotorcraft, prevent the passage of 
any object that could restrict fuel flow or damage any fuel system 
component.
* * * * *
0
18. Amend Sec.  29.1019 by revising paragraph (a)(5) to read as 
follows:

[[Page 50592]]

Sec.  29.1019  Oil strainer or filter.

    (a) * * *
    (5) An oil strainer or filter that has no bypass, except one that 
is installed at an oil tank outlet, must have a means to connect it to 
the warning system required in Sec.  29.1305(a)(19).
* * * * *
0
19. Amend Sec.  29.1305 by revising paragraphs (a)(5), (11), and (12) 
and adding (b)(4) to read as follows:


Sec.  29.1305  Powerplant instruments.

    (a) * * *
    (5) A means to indicate manifold pressure for each reciprocating 
engine of the altitude type;
* * * * *
    (11) A means to indicate the gas temperature for each turbine 
engine;
    (12) A means to indicate the gas producer speed for each turbine 
engine;
* * * * *
    (b) * * *
    (4) For each Category A rotorcraft for which OEI Training Mode is 
requested, a means must be provided to indicate to the pilot the 
simulation of an engine failure, the annunciation of that simulation, 
and a representation of the OEI power being provided.
* * * * *
0
20. Revise Sec.  29.1309 to read as follows:


Sec.  29.1309  Equipment, systems, and installations.

    The equipment, systems, and installations whose functioning is 
required by this subchapter must be designed and installed to ensure 
that they perform 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 requirements also apply:
    (a) The design of each item of equipment, system, and installation 
must be analyzed separately and in relation to other rotorcraft systems 
and installations 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 operating conditions.
    (b) Each item of equipment, system, and installation must be 
designed and installed so that:
    (1) The occurrence of any catastrophic failure condition is 
extremely improbable;
    (2) The occurrence of any minor failure condition is no more than 
probable; and
    (3) For the occurrence of any other failure condition, the 
probability of the failure condition must be inversely proportional to 
its consequences.
    (c) A means to alert the crew in the event of a failure must be 
provided when an unsafe system operating condition exists and to enable 
them to take corrective action. Systems, controls, and associated 
monitoring and crew alerting means must be designed to minimize crew 
errors that could create additional hazards.
    (d) Compliance with the requirements 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, including malfunctions and 
misleading data and input from external sources;
    (2) The effect of multiple failures and latent failures;
    (3) The resulting effects on the rotorcraft and occupants, 
considering the stage of flight and operating conditions; and
    (4) The crew warning cues and the corrective action required.
0
21. Amend Sec.  29.1329 by revising the section heading, adding 
introductory text, and revising paragraphs (a), (d), and (e) to read as 
follows:


Sec.  29.1329  Automatic flight guidance and control system.

    For the purpose of this subpart, an automatic flight guidance and 
control system may consist of an autopilot, flight director, or a 
component that interacts with stability augmentation or trim.
    (a) Each automatic flight guidance and control system must be 
designed so that it:
    (1) Can be overpowered by the pilot to allow control of the 
rotorcraft;
    (2) Provides a means to disengage the system by the pilot to 
prevent it from interfering with the control of the rotorcraft; and
    (3) Provides a means to indicate to the flight crew its current 
mode of operation. Selector switch position is not acceptable as a 
means of indication.
* * * * *
    (d) The system must be designed so that, within the range of 
adjustment available to the pilot, it cannot produce hazardous loads on 
the rotorcraft, or create hazardous deviations in the flight path, 
under any flight condition appropriate to its use or in the event of a 
malfunction.
    (e) If the automatic flight guidance and control system integrates 
signals from auxiliary controls or furnishes signals for operation of 
other equipment, there must be a means to prevent improper operation.
* * * * *
0
22. Amend Sec.  29.1333 by revising paragraph (a) to read as follows:


Sec.  29.1333  Instrument systems.

* * * * *
    (a) For pneumatic systems, only the required flight instruments for 
the first pilot may be connected to that operating system.
* * * * *


Sec.  29.1335  [Removed]

0
23. Remove Sec.  29.1335.
0
24. Amend Sec.  29.1351 by adding paragraphs (e) and (f) to read as 
follows:


Sec.  29.1351  General.

* * * * *
    (e) Electrical equipment, controls, and wiring must be installed so 
that operation of any one unit or system of units will not adversely 
affect the simultaneous operation of any other electrical unit or 
system essential to safe operation.
    (f) Cables must be grouped, routed, and spaced so that damage to 
essential circuits will be minimized if there are faults in heavy 
current-carrying cables.
* * * * *
0
25. Revise Sec.  29.1353 to read as follows:


Sec.  29.1353  Energy storage systems.

    Energy storage systems must be designed and installed as follows:
    (a) Energy storage systems must provide automatic protective 
features for any conditions that could prevent continued safe flight 
and landing.
    (b) Energy storage systems must not emit any explosive or toxic 
gases, smoke, or fluids except through designed venting provisions and 
must not accumulate in hazardous quantities within the rotorcraft.
    (c) Corrosive fluids or gases that escape from the system must not 
damage surrounding structures, adjacent equipment, or systems necessary 
for continued safe flight and landing.
    (d) The maximum amount of heat that can be generated during any 
operation or under any failure condition of the energy storage system 
or its individual components must not result in any hazardous effect on 
rotorcraft structure, equipment, or systems necessary for continued 
safe flight and landing.
    (e) Energy storage system installations required for continued safe 
flight and landing of the rotorcraft must have monitoring features and 
a means to indicate to the pilot the status of all critical system 
parameters.
0
26. Amend Sec.  29.1517 by revising the section heading to read as 
follows:

[[Page 50593]]

Sec.  29.1517  Limiting height-velocity envelope.

* * * * *
0
27. Amend Sec.  29.1545 by revising paragraph (b) to read as follows:


Sec.  29.1545  Airspeed indicator.

* * * * *
    (b) The following markings must be made:
    (1) A red line:
    (i) For rotorcraft other than helicopters, at VNE.
    (ii) For helicopters, at a VNE (power-on).
    (iii) For helicopters, at VNE (power-off). If 
VNE (power-off) is less than VNE (power-on) and 
both are simultaneously displayed, the red line at VNE 
(power-off) must be clearly distinguishable from the red line at 
VNE (power-on).
    (2) [Reserved]
    (3) For the caution range, a yellow range.
    (4) For the normal operating range, a green or unmarked range.
* * * * *
0
28. Amend Sec.  29.1549 by revising paragraphs (a) through (d) to read 
as follows:


Sec.  29.1549  Powerplant instruments.

* * * * *
    (a) Each maximum and, if applicable, minimum safe operating limit 
must be marked with a red line;
    (b) Each normal operating range must be marked as a green or 
unmarked range;
    (c) Each takeoff and precautionary range must be marked with a 
yellow range or yellow line;
    (d) Each engine or propeller range that is restricted because of 
excessive vibration stresses must be marked with red ranges or red 
lines; and
* * * * *
0
29. Amend Sec.  29.1555 by revising paragraph (c)(1) to read as 
follows:


Sec.  29.1555  Control markings.

* * * * *
    (c) * * *
    (1) For fuel systems having no selector controls, the usable fuel 
capacity of the system must be indicated at the fuel quantity indicator 
unless it is:
    (i) Provided by another system or equipment readily accessible to 
the pilot; and
    (ii) Contained in the limitations section of the rotorcraft flight 
manual.
* * * * *
0
30. Amend Sec.  29.1587 by revising paragraph (b)(6) to read as 
follows:


Sec.  29.1587  Performance information.

* * * * *
    (b) * * *
    (6) The height-velocity envelope except for rotorcraft 
incorporating this as an operating limitation;
* * * * *
0
31. Amend appendix B to part 29 by revising paragraphs VIII 
introductory text and VIII(b)(5)(i) to read as follows:

Appendix B to Part 29--Airworthiness Criteria for Helicopter Instrument 
Flight

* * * * *
    VIII. Equipment, systems, and installation. The basic equipment and 
installation must comply with Sec. Sec.  29.1303, 29.1431, and 29.1433, 
with the following exceptions and additions:
* * * * *
    (b) * * *
    (5) * * *
    (i) For pneumatic systems, only the required flight instruments for 
the first pilot may be connected to that operating system;
* * * * *

    Issued under authority provided by (Consult AGC) 49 U.S.C. 
106(f), 44701(a), and 44703 in Washington, DC, on October 19, 2017.
David W. Hempe,
Deputy Executive Director for Regulatory Operations, Aircraft 
Certification Service.
[FR Doc. 2017-23360 Filed 10-31-17; 8:45 am]
 BILLING CODE 4910-13-P