Document ID: FAA-2006-25414-0009
Agency: faa
Document Type: Rule
Title: Performance and Handling Qualities Requirements for Rotorcraft
Posted Date: 2008-02-29T05:00Z

[Federal Register: February 29, 2008 (Volume 73, Number 41)]
[Rules and Regulations]               
[Page 10987-11002]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr29fe08-9]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

 14 CFR Parts 27 and 29

[Docket No.: FAA-2006-25414; Amendment Nos. 27-44 and 29-51]
RIN 2120-AH87

 
Performance and Handling Qualities Requirements for Rotorcraft

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: This final rule provides new and revised airworthiness 
standards for normal and transport category rotorcraft due to 
technological advances in design and operational trends in normal and 
transport rotorcraft performance and handling qualities. The changes 
enhance the safety standards for performance and handling qualities to 
reflect the evolution of rotorcraft capabilities. This rule harmonizes 
U.S. and European airworthiness standards for rotorcraft performance 
and handling qualities.

DATES: These amendments become effective on March 31, 2008. Affected 
parties, however, do not have to comply with the information collection 
requirements of this rule until the OMB approves the FAA's request for 
this information collection requirement. The FAA will publish a 
separate document notifying you of the OMB Control Number and the 
compliance date(s) for the information collection requirements of this 
rule.

FOR FURTHER INFORMATION CONTACT: For technical questions concerning 
this final

[[Page 10988]]

rule contact Jeff Trang, Rotorcraft Standards Staff, ASW-111, Federal 
Aviation Administration, Fort Worth, Texas 76193-0111; telephone (817) 
222-5135; facsimile (817) 222-5961, e-mail jeff.trang@faa.gov. For 
legal questions concerning this final rule contact Steve Harold, 
Directorate Counsel, ASW-7G, Federal Aviation Administration, Fort 
Worth, Texas 76193-0007, telephone (817) 222-5099; facsimile (817) 222-
5945, e-mail steve.c.harold@faa.gov.

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 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, Section 44701, ``General 
requirements,'' Section 44702, ``Issuance of Certificates,'' and 
section 44704, ``Type certificates, production certificates, and 
airworthiness certificates.'' Under section 44701, the FAA is charged 
with prescribing regulations and minimum standards for practices, 
methods, and procedures the Administrator finds necessary for safety in 
air commerce. Under section 44702, the FAA may issue various 
certificates including type certificates, production certificates, and 
airworthiness certificates. Under section 44704, the FAA shall issue 
type certificates for aircraft, aircraft engines, propellers, and 
specified appliances when the FAA finds that the product is properly 
designed and manufactured, performs properly, and meets the regulations 
and minimum prescribed standards. This regulation is within the scope 
of that authority because it would promote safety by updating the 
existing minimum prescribed standards used during the type 
certification process to reflect the enhanced performance and handling 
quality capabilities of rotorcraft. It would also harmonize this 
standard with international standards for evaluating the performance 
and handling qualities of normal and transport category rotorcraft.

Background

    Due to technological advances in design and operational trends in 
normal and transport rotorcraft performance and handling qualities, new 
and revised airworthiness standards have been developed. Some current 
part 27 and part 29 regulations do not reflect safety levels attainable 
by modern aircraft and FAA-approved equivalent level of safety 
findings. In fact, it has been more than 20 years since the last major 
promulgation of rules that address rotorcraft performance and handling 
qualities (Amendments 29-24 and 27-21).\1\ Since then, the FAA has 
developed policies and procedures that address certain aspects of these 
requirements to make the rotorcraft airworthiness standards workable 
within the framework of later rotorcraft designs and operational needs. 
Additionally, most rotorcraft manufacturers have routinely exceeded the 
minimum safety requirements in current part 27 and part 29 regulations.
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    \1\ 49 FR 44433 and 49 FR 44436 respectively, November 6, 1984.
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History of the NPRM

    On January 20, 1995, the FAA tasked the Performance and Handling 
Qualities Harmonization Working Group (PHQHWG) to ``review Title 14 
Code of Federal Regulations part 27 and Appendix B, and part 29 and 
Appendix B, and supporting policy and guidance material for the purpose 
of determining the course of action to be taken for rulemaking and/or 
policy relative to the issue of harmonizing performance and handling 
qualities requirements.'' The PHQHWG, which included broad membership 
from government authorities and industry representatives throughout the 
international rotorcraft community, met a total of ten times beginning 
in March 1995 to ensure participation by all interested parties early 
in the rulemaking process. Based on the recommendations of the PHQHWG, 
we published a notice of proposed rulemaking (NPRM 06-11) \2\ in the 
Federal Register on July 25, 2006. The comment period for that NPRM 
closed on October 23, 2006.
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    \2\ 72 FR 142, Docket Number: FAA-2006-25414.
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Summary of Comments

    The FAA received a total of 34 comments to the NPRM from four 
commenters: Erickson Air-Crane, Transport Canada, and three 
individuals, two of whom submitted their comments jointly. One 
commenter agreed with the proposed changes but had a comment relating 
to our economic evaluation. The remaining 33 comments related to 
specific proposed rule changes and included suggested changes, as 
discussed more fully in the discussion of the final rule below.

Discussion of the Final Rule

Weight Limits (Sec. Sec.  27.25, 29.25)

    The FAA proposed Sec.  27.25(a)(1)(iv) to formalize previous 
equivalent level of safety findings by establishing a maximum allowable 
weight if the requirements in Sec.  27.79 or Sec.  27.143(c)(1) cannot 
be met. The equivalent level of safety is attained by prohibiting 
certain operations and including limitations in the Rotorcraft Flight 
Manual (RFM) that reflect the actual capability of the aircraft.
    One commenter suggested that the proposed changes potentially lower 
the level of safety currently required under part 27 standards, are 
redundant and unnecessary, appear to delete the low-speed 
controllability requirements as a component in establishing the maximum 
weight under Sec.  27.25(a)(1)(iii), and therefore should be withdrawn. 
The commenter stated that under the current standard the flight 
requirements that typically establish the maximum weight for a 
helicopter with a single main rotor are in-ground effect (IGE) hover 
performance (Sec.  27.73), height-velocity (Sec.  27.79), and low-speed 
controllability (Sec.  27.143). The commenter further stated that the 
structure of Sec.  27.25 will always establish the maximum weight at a 
value that allows compliance with Sec. Sec.  27.79 and 27.143(c)(1) 
because the applicant will always select the weights allowed by Sec.  
27.25(a)(1)(iii) to show compliance with Sec. Sec.  27.73, 27.79 and 
27.143. Under the scenario the FAA used to justify the proposed change 
(making an equivalent level of safety finding to Sec.  27.143(c) and 
statements in advisory material for Sec.  29.143(c) that relate to 
possible removal, under certain circumstances, of operating limitations 
based on any hover controllability condition), the commenter stated 
that the FAA intends to delete the low-speed controllability 
requirements of the current rule as parameters for establishing maximum 
weight. The commenter maintained that this would reduce the margin of 
safety for helicopter operations, particularly above sea level, and 
would require exceptional piloting skills or exceptionally favorable 
conditions in order to conduct safe operations. Such requirements are 
prohibited by certain regulations, such as Sec.  27.51(a)(1).
    We disagree with a majority of these comments. Proposed Sec.  
27.25(a)(1)(iv) is not redundant or unnecessary because it provides an 
additional standard, rather than a replacement standard, for 
determining the maximum weight. Recent certifications have resulted in 
rotorcraft designs that have been unable

[[Page 10989]]

to meet the current standards for controllability near the ground 
(Sec.  27.143 Controllability and maneuverability) while at the maximum 
weight established at 7,000 feet density altitude when meeting the 
standards for performance at minimum operating speed (Sec.  27.73) and 
for establishing the respective limiting height-speed envelope (Sec.  
27.79). For those certification projects, we have permitted the 
applicant to show compliance through equivalent level of safety 
findings. In those cases, this new standard would allow for weight-
altitude-temperature (WAT) limitations to be established for a part 27 
rotorcraft that cannot meet the requirements of Sec.  27.143(c) at 
7,000 feet. The rotorcraft would then be required to operate within the 
weights, altitudes, and temperatures specified by those WAT 
limitations. This ``part 29 methodology,'' which imposes WAT 
limitations not usually required of normal category rotorcraft, 
therefore raises the minimum level of safety by restricting the 
aircraft from operating in those environmental conditions where the 
low-speed controllability requirements cannot be met.
    As alluded to by the commenter, these equivalent level of safety 
prohibitions and limitations have historically been obtained through 
use of a certification methodology analogous to that for part 29 
rotorcraft certification. They do not circumvent or eliminate the low 
speed controllability requirements for part 27 rotorcraft. As 
previously noted, one factor we have used in establishing WAT 
limitations is the low-speed controllability requirement of Sec.  
29.143(c). After these changes are effective, the low-speed 
controllability requirement of Sec.  27.143(c) will remain a factor in 
establishing the WAT limitations. While we partially agree with the 
commenter's concerns about operating limitations being a greater 
workload on pilots, we do not believe that any new requirements 
proposed in this rule are beyond the scope of normal piloting 
responsibilities. Whether such data are provided in the Rotorcraft 
Flight Manual (RFM) as performance data or in the Limitations Section 
should not materially affect pilot workload. We agree with the 
commenter that certain environmental conditions may require increased 
pilot vigilance in determining wind speed and direction in order to 
adhere to some limitations and prohibitions. However, we believe that 
following such limitations should not require exceptional piloting 
skill. Furthermore, this standard does not reduce the margin of safety 
because, historically, such a margin of safety was maintained by an 
equivalent level of safety finding. Under the new standard, which 
adopts this equivalent level of safety as another alternative, 
prohibiting and limiting certain operations will maintain, not lower, 
that established level of safety. Accordingly, we are adopting the 
changes as proposed.
    We proposed to amend Sec.  29.25 by requiring that the maximum 
weights, altitudes, and temperatures demonstrated for compliance with 
Sec.  29.143(c), which may also include wind azimuths, become operating 
limitations for Category B rotorcraft with a passenger seating capacity 
of nine or less. Such limitations are necessary to ensure safe aircraft 
operations within the demonstrated performance envelope of such 
rotorcraft.
    Four comments were received regarding Sec.  29.25. One commenter 
stated that the intent and applicability in this proposed rule change 
is confusing in the context of discussions associated with previous 
amendments to part 29 of the regulations and associated advisory 
material. The commenter recommended that the paragraph be rewritten to: 
(1) Clarify how this paragraph affects the relief granted to Category B 
rotorcraft at Amendment 29-24; (2) address maximum safe wind 
limitations in Sec.  29.1583; and (3) make the paragraph applicable to 
all Category B rotorcraft, not just those having a passenger capacity 
of nine or less, if the intent of the change is to grant relief under 
certain conditions from any hover controllability conditions determined 
under Sec.  29.143(c).
    The FAA does not agree that the intent and applicability of the 
proposed change is confusing in the context of previous amendments to 
part 29 and the associated advisory material. As explicitly stated in 
the proposed change to Sec.  29.25(a)(4) this paragraph of the 
regulation applies only to Category B rotorcraft with nine or less 
passenger seats. Even though there may be some imprecise wording in our 
advisory material, we chose to exclude Category B rotorcraft with ten 
or more passenger seats from this change to ensure that a higher level 
of safety is maintained for those transport category rotorcraft 
configured for 10 or more passenger seats. In short, we expect a higher 
level of safety to be applied to all Category A rotorcraft and most 
Category B rotorcraft. For those Category B rotorcraft having nine or 
less passenger seats, in prior certifications in which the current 
standards for controllability near the ground (Sec.  29.143(c)) could 
not be met, we have allowed the applicant to show compliance through an 
equivalent level of safety finding. We accepted these findings as 
providing the same level of safety as that for part 27 certifications, 
which also allows for configurations of no more than nine passenger 
seats. In those certification projects, this new standard would allow 
for demonstrated wind velocities and azimuths to be included as an 
operating limitation, which must be stated as such in the RFM. That is, 
for those part 29, Category B rotorcraft with nine or less passenger 
seats, we believe that by requiring the wind operating envelope to be a 
limitation, the proposed standard provides the same level of safety as 
in the standards prescribed by part 27, which also limits the seating 
capacity to nine or less passenger seats. This methodology is 
consistent with the standards adopted by Amendments 29-21 and 29-24, 
which, among other things, established different criteria for Category 
A and Category B rotorcraft certification in Sec.  29.1 as a function 
of both aircraft weight and maximum passenger seating capacity. We 
believe that the proposed change is materially consistent with the 
current guidance material in Advisory Circular (AC) 29-2C, which only 
will need to be revised to reflect the requirement that the appropriate 
limitations be included in the RFM for these aircraft. Even though 
previous amendments did not specifically require that operating 
envelopes be included in the limitations section of the RFM for these 
aircraft, the proposed change makes this a requirement to further 
increase the safety standards. Further, because this standard deals 
with aircraft weight for various conditions--maximum weights, 
altitudes, and temperatures (WAT)--we opted to place the limitations 
requirement in this regulation, rather than in Sec.  29.1583, to 
further emphasize that the maximum WAT conditions at which the 
rotorcraft can safely operate near the ground with maximum wind 
velocity are limitations and may also include other demonstrated wind 
velocities and azimuths.
    Another commenter stated that revising the rule by addition of a 
new paragraph potentially lowers the level of safety established for 
part 29 standards; potentially shifts the burden for maintaining the 
currently established level of safety from the type design to the 
flight crew; and that maintaining the current version of Sec.  29.25(a) 
is satisfactory and need not be changed. The commenter therefore 
recommended that the proposed change to Sec.  29.25(a) be withdrawn. 
The commenter stated that the low-speed-controllability rule

[[Page 10990]]

consists of two elements, wind speed and weight. The commenter further 
stated that, under current regulations, all part 29 Category B 
rotorcraft are at a competitive disadvantage when compared to 
similarly-sized part 27 rotorcraft because, for part 27 rotorcraft, 
there is no requirement to take-off and land above 7,000 feet density 
altitude at a weight which allows all-azimuth low speed controllability 
in winds of at least 17 knots above 7,000 feet density altitude. The 
commenter asserts that part 29 transport category rotorcraft must be 
designed to operate at the maximum weight that allows compliance with 
Sec.  29.143(c) at each takeoff and landing altitude. If the low speed 
requirement is deleted for part 29 Category B rotorcraft with nine or 
less passenger seats as proposed, the commenter believes the part 29 
flight crew of these rotorcraft will be required to compensate by being 
more alert to the wind conditions when operating near maximum weight. 
Because the margin of safety currently provided by the part 29 design 
may no longer be included in the design of the rotorcraft, the 
commenter contends that this requirement would shift the burden for 
maintaining the currently established level of safety from the type 
design holder to the flight crew.
    The FAA does not agree that these requirements will result in a 
lower safety standard for part 29 or that the requirement potentially 
shifts the burden for maintaining safety from the type design holder to 
the flight crew. Not only is this requirement a safety improvement, but 
critical safety information such as maximum weight, altitude, and 
temperature operating limits (which may include limited wind azimuths) 
would be listed in the Limitations Section of the RFM. Currently, we 
require that information to be placed in the Limitations Section of the 
RFM only for Category A rotorcraft. Our position as reflected in the 
preamble of the NPRM (82-12) \3\ leading to Amendment 29-24, states, in 
part, ``The FAA considers the 17-knot controllability requirement an 
appropriate minimum safety requirement for Category A rotorcraft. * * * 
This proposal would add the requirement that the wind value be placed 
in the Flight Manual as a limitation for Category A rotorcraft. * * * 
In roles envisioned for utility rotorcraft and those carrying less than 
10 passengers, takeoffs and landings are frequently conducted from 
sites where wind information is not readily obtainable. To require this 
wind information as an operating limitation for Category B is 
impractical.'' However, we have reevaluated our position relating to 
operating limitations and are now requiring this information for 
Category B rotorcraft with nine or less passenger seats be placed in 
the Limitations Section, for the same reasons described in our 
disposition of the first three comments to this section.
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    \3\ 47 FR 37806-01, August 26, 1982, Docket  23266.
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    The commenter is correct that, under current regulations, all part 
29 Category B rotorcraft must be designed to operate at the maximum 
weight that allows compliance with Sec.  29.143(c) at each takeoff and 
landing altitude, and that for part 27 rotorcraft, there is no 
requirement to demonstrate all-azimuth low speed controllability in 
winds of at least 17 knots, above 7,000 feet density altitude and at 
the maximum weight. The commenter stated that this places part 29, 
Category B rotorcraft at a competitive disadvantage when compared to 
similarly-sized part 27 rotorcraft. We disagree. For Category B 
rotorcraft having nine or less passenger seats, in prior certifications 
in which the current standards for controllability near the ground 
(Sec.  29.143(c)) could not be met, we have allowed the applicant to 
show compliance through equivalent level of safety findings. We 
accepted these findings as providing the same level of safety as that 
for part 27 certifications, which also allows for no more than nine 
passenger seats, by allowing operating limitations in the RFM which may 
include wind velocities and azimuths. In those certification projects, 
this new standard would allow for demonstrated wind velocities and 
azimuths to be included as an operating limitation in the RFM. That is, 
for those part 29, Category B rotorcraft with nine or less passengers, 
we believe that by requiring wind operating envelope to be a 
limitation, the new standard provides the same level of safety as in 
the standards prescribed by part 27, which also limits the seating 
capacity to nine or less passenger seats.
    As discussed earlier, the FAA did not intend to delete the low 
speed requirement for part 29 Category B rotorcraft with nine or less 
passenger seats. One factor we have used in establishing WAT 
limitations is the low-speed controllability requirement of Sec.  
29.143(c), which this final rule now formalizes.

Performance at Minimum Operating Speed (New Sec.  27.49)

    We proposed to re-designate Sec.  27.73 as Sec.  27.49 and add a 
requirement to determine the out-of-ground effect (OGE) hover 
performance, because OGE operations have become commonplace. The 
proposed change mandates that OGE hover data be determined throughout 
the range of weights, altitudes, and temperatures; most manufacturers 
already present this data in the RFM.
    The FAA received a comment, outside of our proposed rule change, 
suggesting that in this final rule, where we are re-designating Sec.  
27.73 as Sec.  27.49, that we revise paragraph (a)(2)(ii) to encompass 
the entire flight envelope requested by the applicant, including the 
temperature-altitude hover ceiling requirements where the temperature 
at sea level is well above the minimum standard 100 [deg]F condition 
envisioned in Sec.  27.1043(b). The commenter further stated that, if 
we adopt their suggested change to re-designate Sec.  27.49(a)(2)(ii), 
for consistency we should revise Sec. Sec.  27.51, 27.79(a)(1) and 
(a)(2), and 27.143(c)(1) to require turbine-powered rotorcraft to 
demonstrate compliance at maximum weight from sea level at temperatures 
established under Sec.  27.1043(b) to 2,500 feet pressure altitude at a 
temperature corresponding to the established sea level temperature 
decreased by the standard lapse rate. The commenter also stated that 
the FAA should consider revising the 7,000 feet density altitude 
standard in proposed Sec. Sec.  27.51(b), 27.79(a)(1), and 27.143(c)(1) 
and (c)(2) to 7,000 feet density altitude with temperature 
corresponding to the sea level temperature established in compliance 
with Sec.  27.1043(b) decreased by the standard lapse rate. The 
commenter further stated that these changes would acknowledge the 
increased capability of turbine-powered rotorcraft by requiring 
compliance at the edge of the envelope requested, not to a single 
density altitude, which may not reflect the intended operational 
envelope of the rotorcraft. Although this comment may have merit, it is 
beyond the scope of our proposals and is not adopted. We may consider 
it in future rulemaking actions. Accordingly, it is adopted as 
proposed.

Takeoff (Sec.  27.51), Landing (Sec.  27.75), and Engines (Sec.  
27.903)

    We received no comments on these proposals; all three are adopted 
as proposed.
    We proposed to revise Sec.  27.51 to recognize in the standard that 
the most critical center-of-gravity (CG) may not be the extreme forward 
CG, and require that tests be performed at the most critical CG 
configuration and at the maximum weight for which takeoff certification 
is requested. Further, we proposed to clarify the requirement to

[[Page 10991]]

demonstrate safe landings after an engine failure at any point along 
the takeoff path up to the maximum takeoff altitude or 7,000 feet, 
whichever is less, to explicitly state that the altitudes cited are 
density altitudes.
    We proposed to revise Sec.  27.75(a) to: (1) State the required 
flight condition in more traditional rotorcraft terminology; (2) 
require multi-engine helicopters to demonstrate landings with one 
engine inoperative and initiated from an established approach; and (3) 
replace the word ``glide'' with the word ``autorotation.''
    We proposed to add paragraph Sec.  27.903(d) to require engine 
restart capability, which is a fundamental necessity for any aircraft 
to minimize the risk of a forced landing. A restart capability will 
enhance safety, even if it may not be useful in every case such as when 
engine damage exists or when there is insufficient altitude to 
implement the engine restart procedure. We intend that the restart 
procedure be included in the RFM.

Glide Performance (Sec.  27.71)

    One commenter noted that the word ``glide'' has been replaced with 
``autorotation'' in the proposed text of Sec.  27.143. However, the 
title of Sec.  27.71 remains ``Glide Performance.'' The commenter 
recommended that the title of Sec.  27.71 be changed to ``Autorotation 
Performance,'' to provide consistency with the proposed changes. The 
FAA agrees with the comment and the title has been changed.

Performance at Minimum Operating Speed (Sec.  27.73)

    One commenter noted that in our proposed re-designation of current 
Sec.  27.73 to Sec.  27.49, we proposed to change the ambient 
temperature in paragraph (a)(2)(ii) from ``[deg] F'' to ``[deg] C.'' 
Consequently, the commenter recommended that all sections of part 27 
containing temperature callouts likewise be revised. We disagree. The 
NPRM does not change the ambient temperature callout from degrees-
Fahrenheit to degrees-Celsius. Rather, it recognizes degrees-Celsius in 
addition to degrees-Fahrenheit when making the temperature callout. 
Incorporating similar changes to other temperature callouts will be 
considered for future changes to part 27. Accordingly, the change is 
adopted as proposed.

Limiting Height--Speed Envelope (Sec.  27.79)

    We proposed to revise Sec.  27.79(a)(1) to include the words 
``density altitude'' after ``7,000 feet.'' We also proposed to revise 
Sec.  27.79(a)(2) by removing ``lesser'' from the first sentence, 
reflecting that current OGE weights for helicopters are not necessarily 
less than the maximum weight at sea level. Finally, we proposed to 
remove the term ``greatest power'' from Sec.  27.79(b)(2) and replace 
it with language that more clearly states the power to be used on the 
remaining engine(s) for multi-engine helicopters. This ``minimum 
installed specification power'' is the minimum uninstalled 
specification power corrected for installation losses.
    One commenter to the proposed language suggested that the FAA seems 
to be aligning the sections of part 27 with part 29, as was proposed 
with the re-designation of Sec.  27.73 as Sec.  27.49. Consequently, 
the commenter recommended that Sec.  27.79 be re-designated as Sec.  
27.87. The FAA agrees that this paragraph re-designation better aligns 
the requirements for performance at minimum operating speed in part 27 
and part 29. Furthermore, the re-designating of the paragraph is 
administrative in nature and imposes no additional requirements on 
applicants. Accordingly, the recommendation is adopted as proposed.
    The second commenter noted that since the height-velocity (H-V) 
envelope for part 27 aircraft is not a limitation, the word 
``limiting'' should be deleted from the title of Sec.  27.79 and from 
any other references to the H-V envelope contained in part 27. The FAA 
agrees with the comment, since Sec.  27.1587 requires that the H-V 
envelope be published in the RFM as performance information. 
Accordingly, the title of the paragraph is changed.

Controllability and Maneuverability (Sec. Sec.  27.143, 29.143)

    We proposed to revise Sec. Sec.  27.143(a)(2)(v) and 
29.143(a)(2)(v) to replace the word ``glide'' with ``autorotation.'' We 
proposed to re-designate portions of Sec.  27.143, and to rewrite 
Sec. Sec.  27.143(c) and 29.143(c) to more clearly state that 
controllability on or near the ground must be demonstrated throughout a 
range of speeds from zero to at least 17 knots. We also proposed to 
clarify the altitude requirement with the addition of the words 
``density altitude.'' We further proposed to revise Sec.  27.143(c)(2) 
to require that controllability be determined at altitudes above 7,000 
feet density altitude if takeoff and landing are scheduled above that 
altitude. Lastly, we proposed to add Sec. Sec.  27.143(d) and 
29.143(d), to require the determination of controllability for wind 
velocities from zero to at least 17 knots OGE at weights selected by 
the applicant. These proposed changes, together with the new OGE hover 
requirement of Sec.  27.49, would increase the level of safety by 
requiring additional performance information.
    Relative to both sections 27.143 and 29.143, one commenter noted 
that the reference to ``paragraph (e)'' in paragraph (b)(4) of the 
current rule (which we did not propose to change in the NPRM) should be 
changed to read ``paragraph (f).'' The FAA agrees. As indicated in the 
NPRM, we proposed to re-designate Sec. Sec.  27.143 and 29.143 
paragraphs (d) and (e) as paragraphs (e) and (f), respectively. 
However, we failed to propose to change the reference in paragraphs in 
Sec. Sec.  27.143 and 29.143(b)(4) from paragraph (e) to paragraph (f). 
That is, we gave no indication that we proposed to delete the exception 
enumerated in (b)(4) to exclude helicopters from the (b)(4) requirement 
if the helicopter demonstrates compliance with current paragraph (e) 
(re-designated paragraph (f)). Because these paragraph re-designations, 
as well as the unchanged provisions of paragraph (b), were intended 
only to continue the current requirements, we believe changing the 
reference in paragraph (b)(4) from (e) to (f) is non-substantive, 
constitutes a correction of an error, is consistent with our intended 
changes without which the proposed change would have unintended 
consequences, and continues the current standard to exclude the same 
helicopters from the provisions of paragraph (b)(4). We have changed 
the reference in the final rule.
    A second comment stated that the NPRM proposes to add requirements 
to determine low-speed controllability: (1) Near the ground for takeoff 
and landing altitudes above 7,000 feet density altitude, and (2) for 
OGE for the altitude range from standard sea level to the maximum 
takeoff and landing altitude capability of the aircraft. The commenter 
stated that under Sec.  27.25(a), the weight selected by the applicant 
to establish the all-azimuth wind velocities would be a factor in 
determining the maximum weight. The commenter stated that this weight 
would undoubtedly be much less than the maximum weight determined under 
the current rule and thus would make the rotorcraft less competitive. 
Further, the commenter assumes that the intent of the proposal is to 
develop additional performance information beyond that currently 
available, to assist the flight crew. The commenter stated that if 
these assumptions are true, the NPRM should be revised to clearly 
indicate that the proposed paragraphs are not applicable as flight 
requirements when establishing the maximum weight under Sec.  27.25(a).

[[Page 10992]]

The FAA does not agree. As noted in the NPRM, the intent of the 
proposed language is to increase the level of safety by providing 
additional performance information in the RFM. This is further 
reflected in the proposed Sec.  27.1587(a)(2), which proposed to 
explicitly require presentation of performance information found in 
meeting the requirements of the proposed Sec.  27.143. Consequently, 
the new Sec.  27.143(d)(4) will not be used in determining the 
rotorcraft's maximum weight under Sec.  27.25(a). Except for the 
reference change in paragraph Sec.  27.143(b)(4), the changes are 
adopted as proposed.
    Another comment suggests that we used the word ``manner'' instead 
of ``maneuver'' in proposed Sec.  29.143(c). The proposed requirement 
reads, in part, ``* * * the rotorcraft can be operated without loss of 
control on or near the ground in any manner appropriate to the type. * 
* *'' The commenter suggests that the word ``manner'' should be changed 
to ``maneuver'' because the latter is used in the current requirement 
and also in the proposed and current requirement in Sec.  27.143(c). We 
agree. The word ``manner,'' as used in the proposed text, is an error. 
We intended to use the word ``maneuver'' in proposed Sec.  29.143(c) 
and we have made that non-substantive change in this final rule.

Static Longitudinal Stability (Sec. Sec.  27.173, 29.173)

    We proposed to clarify Sec. Sec.  27.173(a) and 29.173(a) by 
changing ``a speed'' to ``airspeed.'' We also proposed to combine 
paragraphs (b) and (c) to allow neutral or negative static stability in 
limited areas of the flight envelope, if adequate compensating features 
are present and the pilot can maintain airspeed within five knots of 
the desired trim airspeed under the conditions of Sec. Sec.  27.175 and 
29.175. Such neutral or negative static stability in limited flight 
domains have been allowed for numerous rotorcraft under equivalent 
level of safety findings. Lastly, we proposed to delete the Sec. Sec.  
27.173(c) and 29.173(c) requirements relating to the hover 
demonstration in current Sec. Sec.  27.175(d) and 29.175(d).
    We received no substantive comments relative to the proposed 
changes to Sec.  27.173. One commenter noted that the proposed revision 
to Sec.  29.173(b) has an open parenthesis mark in front of the ``5 
knots'' and suggested that open parenthesis mark should be a ``'' symbol. We agree and have made that change in the final rule. 
The other proposed changes have been adopted as proposed.

Demonstration of Static Longitudinal Stability (Sec. Sec.  27.175, 
29.175)

    We proposed to decrease, in paragraphs (a) and (b) of Sec. Sec.  
27.175 and 29.175, the airspeed range about the specified trim speeds 
to more representative values than are currently contained in the rule. 
We also proposed to add a new paragraph (c) to require an additional 
level flight demonstration point, at a trim airspeed of VNE - 10 knots, 
because the data coverage under the current cruise demonstration speed 
in modern helicopters may no longer represent a normal variation about 
a trim point. Additionally, we proposed to re-designate the current 
paragraph (c) as paragraph (d), and to delete the current paragraph (d) 
containing the hover demonstration, as the safety considerations 
associated with hovering flight are adequately addressed by Sec. Sec.  
27.143(a) and 29.143(a), respectively.
    One commenter suggested that discrepancies may exist between Sec.  
27.175(d)(1) and (2), and Sec. Sec.  27.67 and 27.71. Specifically, 
Sec.  27.175 requires that static longitudinal stability be 
demonstrated in autorotation about the airspeeds for minimum rate-of-
descent and best angle-of-glide. However, Sec.  27.71 requires that the 
minimum rate of descent and the best angle of glide airspeeds be 
determined only for single engine helicopters and multiengine 
helicopters that do not meet Category A engine isolation requirements. 
Therefore, the commenter stated that this requirement would not apply 
to multi-engine helicopters that meet Category A engine isolation 
requirements. The commenter recommended that these sections be 
reconciled for part 27 designs that meet Category A engine isolation 
requirements. The FAA does not agree that any action is necessary. 
While Sec.  27.71 does not have an explicit requirement to determine 
these two autorotation speeds for part 27 rotorcraft that meet Category 
A engine isolation requirements, Sec.  27.141 requires that the 
rotorcraft demonstrate satisfactory flight characteristics for ``any 
condition of speed, power, and rotor r.p.m. for which certification is 
requested; * * *.'' Further, the two trim airspeeds explicitly cited in 
the proposed rule are intended to provide data at the most likely 
operating conditions flown during an autorotation, thereby providing a 
higher level of safety. Consequently, we are adopting the language as 
proposed.
    One commenter stated that the proposed revision to paragraph Sec.  
29.175(b) reads, ``* * * in the climb condition at speeds from Vy-10 
kt, to Vy + 10 kt. * * *'' The commenter recommended that we delete the 
comma after ``Vy-10 kt.'' We agree. That comma in the proposed text is 
a typographical error and has been removed in this final rule. 
Otherwise, the changes are adopted as proposed.

Static Directional Stability (Sec. Sec.  27.177, 29.177)

    We proposed to revise Sec. Sec.  27.177 and 29.177 to provide 
further objective criteria over which the directional stability 
characteristics are evaluated. We also proposed to allow for a minimum 
amount of negative stability around each trim point, which does not 
materially affect the overall safety considerations of static 
directional stability.
    One commenter noted a typographical error in the proposed text of 
Sec.  27.177, in that paragraph (a)(1) has an open parenthesis mark in 
front of ``10 degrees'' and suggests that it should be a ``'' symbol. We agree and have corrected that error in Sec.  
27.177(a)(1) of this final rule. Otherwise, the proposal is adopted as 
proposed.
    Two comments were received regarding Sec.  29.177. In the first 
comment, Transport Canada stated that they do not think that Sec.  
29.177(a)(1) makes sense in relation to Sec.  29.177(a). They recited 
what they assumed we meant by the proposal and stated that ``paragraph 
29.177(a)(1) specifies a range of sideslip angles and the lesser 
sideslip angle in this range will always be the smallest angle in the 
range.'' We do not agree and have not made any changes based on this 
comment. We believe that the commenter has misinterpreted our meaning 
in the ``* * * sideslip angles up to the lesser of--'' language in 
proposed Sec.  29.177(a). This language modifies the four options 
listed in paragraphs Sec.  29.177(a)(1) through Sec.  29.177(a)(4) and 
is intended to mean the lesser value found from each of those four 
subsequent paragraphs. Paragraph 29.177(a)(1) is intended to provide 
options of sideslip angles from trim that are 50[deg] wide (+25[deg] to 
-25[deg]) at the minimum-rate-of-descent airspeed less 15 knots, then 
varying linearly and narrowing to 20[deg] wide (+10[deg] to -10[deg]) 
at the Vne airspeed.
    The second commenter suggested that the phrase in proposed Sec.  
29.177(c) that reads ``paragraph (a) of this paragraph'' be changed to 
read ``paragraph (a) of this section.'' We agree. The correct reference 
is to paragraph (a) of Sec.  29.177. Except for changing the word 
``paragraph'' to ``section'' for proposed Sec.  29.177(c), the other 
changes are adopted as proposed.

[[Page 10993]]

Performance Information (Sec. Sec.  27.1587, 29.1587)

    We proposed to revise Sec.  27.1587(a) to include reference to new 
Sec.  27.49. We also proposed to revise Sec.  27.1587(a)(2)(i) and (ii) 
to specifically include requirements for presenting maximum safe winds 
for OGE operations established in proposed Sec.  27.143. Lastly, we 
proposed to delete Sec.  27.1587(b)(1)(i) and (ii), which were moved 
into Sec.  27.1585(a) by Amendment 27-21 and inadvertently left in 
Sec.  27.1587.
    Three comments were received regarding Sec.  27.1587. The first 
commenter suggested that the term ``maximum wind value'' in Sec.  
27.1587(a)(2)(ii) could be confusing and ambiguous and recommended that 
the term ``maximum wind value'' be replaced with ``in winds of not less 
than 17 knots from all azimuths.'' We disagree. The requirements of 
this proposed rule assume that the requirements of Sec.  27.143(c) can 
be met by the applicant. The proposed change seeks to ensure that 
appropriate performance information will be included in the RFM, 
whether it is 17 knots or some higher demonstrated value.
    The second commenter suggested that Sec.  27.1587(a)(2)(ii) is in 
conflict with the proposed Sec.  27.143(c)(2) and (3). Specifically, 
the former paragraph uses the term ``maximum weight,'' while the latter 
two allow the applicant to select a weight, which may be less than the 
maximum weight. The FAA disagrees. The proposed text of Sec.  
27.1587(a) explicitly requires that the RFM contain information 
determined in accordance with Sec.  27.143(c) and (d). The term 
``maximum weight,'' subsequently used in paragraph (a)(2)(ii) is 
intended to be a further description of the maximum weight used when 
demonstrating compliance with Sec.  27.143(c) and (d).
    The third comment stated that the FAA has no formal definition of 
``maximum safe wind,'' nor is there a flight requirement to demonstrate 
a ``maximum safe wind.'' The commenter recommended that the FAA explain 
the term and include definitions in part 27 and part 29. The FAA agrees 
that the comment may have merit. However, the term is currently used in 
both part 27 and part 29, and has been used throughout the history of 
these regulations, to include Civil Air Regulations 6 and 7, 
predecessors to this regulation. Development of a formal definition may 
be evaluated for incorporation in future rulemaking. Accordingly, the 
changes are adopted as proposed.
    We proposed to revise Sec.  29.1587 to require new performance 
information be included in the RFM, including the requirement for 
presenting maximum safe winds for OGE operations.
    A commenter stated that the proposed paragraphs (a)(7) and (b)(8) 
require, in part, ``* * * the maximum weight for each altitude and 
temperature condition at which the rotorcraft can safely hover in-
ground-effect and out-of-ground effect in winds of not less than 17 
knots. * * *'' The commenter stated that the requirement is redundant, 
is not pertinent to a paragraph referring only to OGE hover 
performance, and that other paragraphs of Sec.  29.1587 already contain 
the in-ground-effect (IGE) hovering requirement. The commenter 
recommended that the IGE requirement be deleted from each proposed 
paragraph. We agree that the ``in-ground-effect'' requirement is 
redundant and unnecessary. In adopting the changes to this section, we 
have deleted the ``in-ground-effect'' hovering requirement from the 
proposed Sec.  29.1587(a)(7) and Sec.  29.1587(b)(8).
    The commenter further stated that the proposed paragraphs (a)(7) 
and (b)(8) conflict with the proposed revision to Sec.  29.143(d). 
Specifically, proposed paragraphs (a)(7) and (b)(8) require the 
applicant to publish performance data for the ``maximum weight,'' 
whereas proposed Sec.  29.143(d) allows a ``weight selected by the 
applicant'' when demonstrating the OGE requirement. The commenter 
stated that the ``weight selected by the applicant'' may not be the 
``maximum weight.'' Therefore, the commenter recommended that Sec.  
29.1587(a)(7) and (b)(8) be changed to reflect the ``weight selected by 
the applicant'' as stated in Sec.  29.143(d). We disagree. Proposed 
Sec.  29.143(d) does allow for a ``weight selected by the applicant'' 
for the controllability and maneuverability standards. However, the 
proposed Sec.  29.1587(a)(7) and (b)(8) also require that OGE 
performance data be provided at minimum operating speeds under Sec.  
29.49 over the ranges of ``weight, altitude, and temperature'' for 
which certification is requested, in addition to performance data at 
the maximum weight for each altitude and temperature at which the 
helicopter can hover safely in winds of not less than 17 knots from all 
azimuths. Consequently, the intent of this final rule is to require new 
OGE hover performance data be provided at the maximum weight used to 
demonstrate compliance with Sec. Sec.  29.49 and 29.143(d).
    The commenter stated that Sec.  29.1587(b)(2) could be revised to 
more clearly indicate that the hover ceiling data is for IGE hovering. 
We agree that making specific reference to the IGE hover ceiling, adds 
clarification, and removes any ambiguity in the requirement. 
Accordingly, the recommendation is adopted.
    The commenter also suggested that since Sec.  29.1587(b)(8) uses 
the term ``winds of at least 17 knots from all azimuths,'' it ``would 
seem reasonable to expect paragraph (b)(4) to be similarly changed.'' 
We do not agree. Section 29.1587(b)(4) assumes that the requirements of 
Sec.  29.143(c) for critical conditions can be met during IGE 
operations. Consequently, the requirements of (b)(4) ensure that, if a 
higher wind value exists that could present an unsafe condition, the 
consideration of those higher wind values are reflected in the 
appropriate performance information in the RFM for the maximum safe 
winds for operations near the ground. Conversely, paragraph (b)(8) 
requires presentation of the maximum weight at which the rotorcraft can 
hover OGE in 17-knot winds from any azimuth.
    The commenter questioned why we proposed to remove the term 
``maximum safe wind'' from current Sec.  29.1587(a)(7) and replace it 
with ``maximum weight for each altitude and temperature condition at 
which the rotorcraft can safely hover in-ground-effect and out-of-
ground effect in winds of not less than 17 knots from all azimuths.'' 
The commenter noted that in Sec.  29.1587(b)(8) the FAA proposed to 
continue to use the current terminology ``maximum safe wind'' but add 
an ``almost separate and distinct parameter,'' that is to say, 
``maximum weight for each altitude and temperature condition at which 
the rotorcraft can safely hover in-ground-effect and out-of-ground 
effect in winds of not less than 17 knots from all azimuths,'' the 
exact language we proposed as replacement language in paragraph (a)(7). 
The commenter stated that there is some apparent confusion over the 
definition and use of the term ``maximum safe wind.'' The commenter 
further postulated that in the proposed paragraph (a)(7), standard 
maximum safe wind seems to be equated with winds established for all-
azimuth low speed controllability as defined in Sec.  29.143(c). 
Conversely, proposed paragraph (b)(8) seems to treat maximum safe wind 
as something other than winds established for all-azimuth low speed 
controllability. The commenter believes that ``maximum safe wind'' 
could be viewed as a range of wind speeds and azimuths for safe 
operation where the wind speed is neither less than the wind speed 
established by Sec.  29.143(c) nor more than

[[Page 10994]]

the demonstrated speed, particularly in non-critical azimuth ranges. 
The commenter stated that the FAA has neither a formal definition of 
``maximum safe wind'' nor a flight requirement to demonstrate a 
``maximum safe wind,'' and therefore recommended that the FAA explain 
the term and include a formal definition in part 27 and part 29. The 
FAA disagrees. In paragraphs (a)(7) and (b)(8), we proposed to more 
explicitly relate these requirements to those of Sec.  29.143. The term 
``maximum safe wind'' is also included in paragraph (b)(8) to provide 
for the presentation of additional wind speeds and azimuths in which 
Category B rotorcraft may be safely operated. While this term is not 
formally defined, it has been used in the certification standards since 
the existence of Civil Air Regulations 6 and 7; development of a formal 
definition will be evaluated in future rule changes. We did not make 
any changes to Sec.  21.1587 based on these comments.

Airworthiness Criteria of Helicopter Instrument Flight (Appendix B to 
Part 27 and Appendix B to Part 29)

    We proposed to amend paragraph V(a) to allow for a minimal amount 
of neutral or negative stability around trim and to replace the phrase 
``in approximately constant proportion'' with ``without 
discontinuity.'' We also proposed to require that the pilot be able to 
maintain the desired heading without exceptional skill or alertness. 
Additionally, we proposed to reorganize paragraphs VII(a)(1) and 
VII(a)(2) and to revise them to specify the standards that must be met 
when considering a stability augmentation system failure. Finally, in 
paragraph V(b) of Appendix B to Part 29, we proposed to replace the 
word ``cycle'' with the correct word, ``cyclic.''
    One commenter noted that, in the proposed change to paragraph 
VII(a) of Appendix B to Part 27 and Part 29, we replaced the term 
``failure condition'' with the term ``failure.'' The commenter stated 
that, ``in the context of a systems safety assessment a `failure' and a 
`failure condition' are two distinctly different things'' and that the 
proposed change represents an alleviation. Consequently, the commenter 
stated support for reinstating the original term ``failure condition'' 
as intended by the ARAC Performance and Handling Qualities Working 
Group. Although not stated specifically in the comment, we believe that 
the commenter is suggesting that the word ``condition'' be inserted 
after the word ``failure'' in the second and third sentences of 
paragraph VII(a). We agree that we should insert the word ``condition'' 
in the two places in paragraph VII(a) but do not agree that, as stated, 
the proposal lessens the safety standard. Rather, we believe that 
omitting the term ``condition,'' as proposed in the NPRM, could result 
in a perceived change to the requirements for the systems safety 
assessment for instrument flight certification or could create 
confusion in future certification activities since its use would not be 
consistent with other current regulations, advisory material, and 
industry practice. No such change was intended by the proposal.
    SAE Aviation Recommended Practice, ARP4761, defines the term 
``failure'' as ``a loss of a function or a malfunction of a system or a 
part thereof.'' It further defines the term ``failure condition'' as 
``a condition with an effect on the aircraft and its occupants, both 
direct and consequential, caused or contributed to by one or more 
failures, considering relevant adverse operation or environmental 
conditions.'' ARP4761 further states that, ``for each failure 
condition, the analyst must assign probability requirements.'' In 
existing certification activities, we accept these definitions for 
assigning probability requirements. In application, the five 
probability classifications (frequent, reasonably probable, remote, 
extremely remote, and extremely improbable) are intended to relate to 
an identified ``failure condition'' resulting from or contributed to by 
the improper operation or loss of a function or functions and not to 
the reliability of specific components or systems. The FAA intends that 
the term ``failure condition'' relate to the assignment of a 
probability requirement (in this case, ``extremely improbable'') to the 
``failure condition,'' and not to the ``failure'' itself. In this 
standard, a Stability Augmentation System (SAS) failure condition, 
under these definitions, requires that the applicant take into 
consideration that the operation is made during instrument flight.
    Because we are concerned that this proposal may be viewed as an 
inadvertent change to the safety standard and the system safety 
analysis requirements associated with SAS for instrument flight 
certification, we have changed the proposed standard and now use the 
term ``failure condition'' in the suggested two locations in paragraph 
VII(a). This change is consistent with the intent of the proposed 
standard, current industry practice, and is the same terminology used 
elsewhere in our regulations and guidance material. The change is 
further consistent with our goal of maintaining harmonized 
certification standards with the European Aviation Safety Agency 
(EASA). The remaining proposals are adopted without change.

Appendix C to Part 27 Criteria for Category A

    One commenter recognized that we did not propose to change Appendix 
C to part 27, but suggested that since we are proposing to revise the 
low speed controllability section of part 27, we should also require 
all-azimuth low speed controllability in winds of not less than 17 
knots at all weights, altitudes and temperatures where Category A 
takeoff and landing operations are requested for certification. The 
commenter stated that current Appendix C to part 27 does not require 
that part 27 rotorcraft certificated for Category A operations meet the 
low speed controllability requirements of Sec.  29.143(c) because that 
requirement is not listed in paragraph C27.2 of Appendix C to part 27. 
The commenter speculated that perhaps ``we reasoned that since the low 
speed controllability requirements of Sec.  27.143(c) and Sec.  
29.143(c) are identical, there was not a need to repeat a requirement 
already in place.'' However, the commenter stated that there is a 
difference; specifically with regards to the altitude range over which 
the two rules apply. The commenter stated that Sec.  27.143(c) applies 
only from sea level to 7,000 feet density altitude, while Sec.  
29.143(c) applies to all altitudes and temperature for takeoff and 
landing requested for certification. The commenter stated that part 27 
rotorcraft certificated for Category A operations should meet the same 
level of safety as that for transport category rotorcraft. We disagree. 
Part 27 rotorcraft certificated for Category A operations were not 
intended to meet the same level of safety as that for transport 
category rotorcraft. If this were the case, Appendix C to part 27 would 
have included all the part 29 requirements for Category A, particularly 
where differences exist between part 27 and part 29. Indeed, different 
Category A certification requirements exist for part 29 rotorcraft, as 
a function of aircraft weight and passenger seating capacity.

Performance at Minimum Operating Speed (New Sec.  27.49)

    We proposed to re-designate Sec.  27.73 as Sec.  27.49 and add a 
requirement to determine the OGE hover performance, because such 
operations have become commonplace. The proposed change mandates that 
OGE hover data be determined throughout the range of weights, 
altitudes, and temperatures;

[[Page 10995]]

most manufacturers already present this data in the RFM.
    Concerning this re-designation of Sec.  27.73 as Sec.  27.49, a 
commenter suggested that we revise paragraph (a)(2)(ii) to encompass 
the entire flight envelope requested by the applicant, including the 
temperature-altitude hover ceiling requirements, where the temperature 
at sea level is well above the minimum standard 100[deg]F condition 
envisioned in Sec.  27.1043(b). The commenter further stated that, if 
we adopt the suggested change to re-designate Sec.  27.49(a)(2)(ii), 
for consistency we should revise Sec. Sec.  27.51, 27.79(a)(1) and 
(a)(2), and 27.143(c)(1) to require turbine-powered rotorcraft to 
demonstrate compliance at maximum weight from sea level at temperatures 
established under Sec.  27.1043(b) to 2,500 feet pressure altitude at a 
temperature corresponding to the established sea level temperature 
decreased by the standard lapse rate. The commenter also stated that 
the FAA should consider revising the 7,000 feet density altitude 
standard in proposed Sec. Sec.  27.51(b), 27.79(a)(1), and 27.143(c)(1) 
and (c)(2) to 7,000 feet density altitude with temperature 
corresponding to the sea level temperature established in compliance 
with Sec.  27.1043(b) decreased by the standard lapse rate.
    The commenter stated that these changes would acknowledge the 
increased capability of turbine-powered rotorcraft by requiring 
compliance at the edge of the requested envelope, not to a single 
density altitude, which may not reflect the intended operational 
envelope of the rotorcraft. Although this comment may have merit, it is 
beyond the scope of our proposals and is not adopted. We may consider 
it in future rulemaking actions.

Takeoff (Sec.  27.51), Landing (Sec.  27.75), and Engines (Sec.  
27.903)

    We received no comments on our proposed changes to these sections. 
All are adopted as proposed, but are included here for informational 
purposes.
    We proposed to revise Sec.  27.51 to recognize in the standard that 
the most critical center-of-gravity (CG) may not be the extreme forward 
CG, and require that tests be performed at the most critical CG 
configuration and at the maximum weight for which takeoff certification 
is requested. Further, we proposed to clarify the requirement to 
demonstrate safe landings after an engine failure at any point along 
the takeoff path up to the maximum takeoff altitude or 7,000 feet, 
whichever is less, to explicitly state that the altitudes cited are 
density altitudes.
    We proposed to revise Sec.  27.75(a) to: (1) State the required 
flight condition in more traditional rotorcraft terminology; (2) 
require multi-engine helicopters to demonstrate landings with one 
engine inoperative and initiated from an established approach; and (3) 
replace the word ``glide'' with the word ``autorotation.''
    We proposed to add paragraph Sec.  27.903(d) to require engine 
restart capability, which is a fundamental necessity for any aircraft 
to minimize the risk of a forced landing. A restart capability will 
enhance safety, even if it may not be useful in every case, such as 
when engine damage exists or when there is insufficient altitude to 
implement the engine restart procedure. We intend to include the 
restart procedure in the RFM.

Economic Evaluation

    Regarding our economic determination, Erickson Air-Crane 
Incorporated asked that we correct the Regulatory Flexibility 
Determination section to show that Erickson is a part 29, rather than a 
part 27, rotorcraft manufacturer; has 600 employees rather than 500; 
and suggested that we recalculate the percentages in the Annual Revenue 
table based on these changes. We concur. We have made these changes and 
do not believe that they materially change the economic determination 
of this rule.

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. An agency may not collect or 
sponsor the collection of information, nor may it impose an information 
requirement unless it displays a currently valid Office of Management 
and Budget (OMB) control number.
    As required by the Act, we submitted a copy of the new information 
requirements to OMB for their review when we published the NPRM. 
Additionally, in the NPRM, we solicited comments from the public on the 
proposed new information collection requirements. No comments relating 
to the proposed new information collection requirements were received. 
Affected parties, however, do not have to comply with the information 
collection requirements of this rule until the OMB approves the FAA's 
request for this information collection requirement. The FAA will 
publish a separate document notifying you of the OMB Control Number and 
the compliance date(s) for the information collection requirements of 
this rule.

International Compatibility

    In keeping with U.S. obligations under the Convention on 
International Civil Aviation, it is FAA policy to comply with 
International Civil Aviation Organization (ICAO) Standards and 
Recommended Practices to the maximum extent practicable. The FAA has 
reviewed the corresponding ICAO Standards and Recommended Practices and 
has identified no ``differences'' with these regulations.

Regulatory Evaluation, Regulatory Flexibility Determination, 
International Trade

Impact Assessment, and Unfunded Mandates Assessment

    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 (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, this 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). This portion of the preamble summarizes the FAA's analysis of 
the economic impacts of this final rule. We suggest readers seeking 
greater detail read the full regulatory evaluation, a copy of which we 
have placed in the docket for this rulemaking.
    In conducting these analyses, FAA has determined that this final 
rule: (1) Has benefits that justify its costs, (2) is not an 
economically ``significant regulatory action'' as defined in section 
3(f) of Executive Order 12866, (3) is not ``significant'' as defined in 
DOT's Regulatory Policies and Procedures; (4) will not have a 
significant economic

[[Page 10996]]

impact on a substantial number of small entities; (5) will not have a 
significant effect on international trade; and (6) will not impose an 
unfunded mandate on state, local, or tribal governments, or on the 
private sector by exceeding the monetary threshold identified. These 
analyses are summarized below.

Total Benefits and Costs of This Rulemaking

    The estimated cost of this final rule is about $558,250 ($364,955 
in present value). The estimated potential benefits of avoiding at 
least one helicopter accident are about $3.9 million ($2.7 million in 
present value).

Who is Potentially Affected by This Rulemaking?

     Operators of U.S.-registered part 27 or 29 rotorcraft, and
     Manufacturers of part 27 or 29 rotorcraft.

Our Cost Assumptions and Sources of Information

     Discount rate--7%.
     Period of analysis--10 years. During this period 
manufacturers will seek new certifications for one large and one small 
part 27 and two large part 29 rotorcraft.
     Value of fatality avoided--$3.0 million (Source: 
``Economic Values for FAA Investment & Regulatory Decisions'' (March 
2004)).

Benefits of This Rule

    The benefits of this final rule consist of the value of lives and 
property saved due to avoiding accidents involving part 27 or 29 
rotorcraft. Over the 10-year period of analysis, the potential benefit 
of this final rule will be at least $3.9 million ($2.7 million in 
present value) by preventing one accident.

Cost of This Rule

    We estimate the costs of this final rule to be about $558,250 
($364,955 in present value) over the 10-year analysis period. 
Manufacturers of 14 CFR part 27 rotorcraft will incur costs of $383,250 
($234,039 in present value) and manufacturers of 14 CFR part 29 
helicopters will incur costs of $175,000 ($130,916 in present value).

Final 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 RFA requires agencies to 
solicit and consider flexible regulatory proposals and to explain the 
rationale for their actions. 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 proposed or 
final 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 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 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.
    This Final Regulatory Flexibility Analysis examines the potential 
costs and benefits to small business entities of a final rule on new 
and revised performance and handling requirements for rotorcraft. The 
rule is intended to revise the flight certification requirements to 
incorporate flight test procedures for performance and handling 
qualities that reflect the evolution of rotorcraft capabilities since 
the last major revisions to this rule.
    In addition the rule reflects an international effort to have 
common rotorcraft certification requirements.
    We used the Small Business Administration guideline of 1,500 
employees or fewer per firm as the criterion for the determination of a 
small business in commercial air service.\4\
---------------------------------------------------------------------------

    \4\ 13 CFR 121.201, Size Standards Used to Define Small Business 
Concerns, Sector 48-49 Transportation, Subsector 481 Air 
Transportation.
---------------------------------------------------------------------------

    In order to determine if the final rule will have a significant 
economic impact on a substantial number of small entities, a list of 
all U.S. rotorcraft manufacturers, who must meet normal and transport 
category rotorcraft airworthy standards under 14 CFR parts 27 and 29, 
respectively was developed.
    Using information provided by three sources: The World Aviation 
Directory, Dunn and Bradstreet's company databases, and SEC filings 
through the Internet, we examined the publicly available revenue and 
employment of all businesses, and eliminated those with more than 1,500 
employees and subsidiaries of larger businesses.
    The results of this methodology are displayed on Table VII-1 
showing 4 U.S. part 27 rotorcraft manufacturers with fewer than 1,500 
employees and one part 29 rotorcraft manufacturer with fewer than 1,500 
employees.
    One comment was received on the NPRM regulatory flexibility 
section. The comment was from Erickson Air-Crane. The regulatory 
flexibility analysis section of the NPRM listed Erickson Air-Crane as a 
part 27 manufacturer with 500 employees. Erickson Air-Crane commented 
that they are a part 29 manufacturer with 600 employees. The 
information provided by Erickson Air-Crane was used in the preparation 
of this final regulatory flexibility determination.

       Table VII-1.--U.S. Small Business Rotorcraft Manufacturers
------------------------------------------------------------------------
           No.                          Name                Employment
------------------------------------------------------------------------
                                 Part 27
------------------------------------------------------------------------
1........................  Hiller Aircraft Corp.........              35
2........................  Brantley Helicopter Industry.              35
3........................  Enstrom Helicopter                        100
                            Corporation.
4........................  Robinson Helicopter Company,              700
                            Inc.
------------------------------------------------------------------------

[[Page 10997]]

                                 Part 29
------------------------------------------------------------------------
1........................  Erickson Air-Crane...........             600
------------------------------------------------------------------------

    Based on the historic number of new rotorcraft certificates over 
the next ten years, we expect that only one of the part 27 smaller 
firms will be affected by this final rule.
    Although most of the proposed requirements intended to revise the 
flight certification requirements are current industry standards and 
support new FAA rotorcraft policy, some will increase costs, while some 
will decrease costs. Sections 27.49, 27.143, 29.143, 27.175, 29.175, 
27.177, and 27.903 will increase costs by requiring manufacturers to 
add additional data and testing procedures to the RFM. Sections 27.173 
and 29.173 on static longitudinal stability will be cost relieving to 
the manufacturers because they delete hover demonstrations that are 
redundant with other requirements.
    As shown in Table VII-2, we estimate the total compliance costs for 
a small part 27 firm's new certification to be $77,000.

  Table VII-2.--Compliance Costs for Small Business Part 27 Rotorcraft
                     Manufacturers per Certification
------------------------------------------------------------------------
                      Rule section                             Cost
------------------------------------------------------------------------
27.49..................................................         $20,075
27.143.................................................          29,300
27.173.................................................         (14,600)
27.175.................................................           3,650
27.177.................................................          20,075
27.903.................................................          18,250
                                                        ----------------
  Total................................................          76,750
------------------------------------------------------------------------

    The annualized cost for this small operator is estimated at $10,928 
($76,750 x 0.142378 \5\).
    As shown in Table VII-3, we estimate the total compliance costs for 
a small part 29 firm's new certification to be $175,000.

  Table VII-3.--Compliance Costs for Small Business Part 29 Rotorcraft
                     Manufacturers per Certification
------------------------------------------------------------------------
                      Rule section                             Cost
------------------------------------------------------------------------
29.143.................................................        $280,000
29.173.................................................        (140,000)
29.175.................................................          35,000
                                                        ----------------
  Total................................................         175,000
------------------------------------------------------------------------

    The annualized cost for this small operator is estimated at $24,916 
($175,000 x 0.142378 \6\).
    The degree to which a small rotorcraft manufacturer can ``afford'' 
the cost of compliance is determined by the availability of financial 
resources. The initial implementation costs of the proposed rule may 
come from either cash flow or be borrowed. As a proxy for the firm's 
ability to afford the cost of compliance, we calculated the ratio of 
the total annualized cost of the proposed rule as a percentage of 
annual revenue. This ratio is a conservative measure as the annualized 
value of the 10-year total compliance cost is divided by one year of 
annual revenue. None of the small business operators potentially 
affected by this proposed rule will incur costs greater than 0.2 
percent of their annual revenue (See Table VII-4).

                    Table VII-4.--Impact of Final Rule on Small U.S. Rotorcraft Manufacturers
----------------------------------------------------------------------------------------------------------------
                                                                      Annual
                      Name                          Employment        revenue       Cert. cost      Percentage
----------------------------------------------------------------------------------------------------------------
                                   U.S. Part 27 Small Rotorcraft Manufacturers
----------------------------------------------------------------------------------------------------------------
Hiller Aircraft Corp............................              35      $7,500,000         $10,928            0.15
Brantley Helicopter Industry....................              35      15,000,000          10,928            0.07
Enstrom Helicopter Corp.........................             100      35,000,000          10,928            0.03
Robinson Helicopter Co., Inc....................             700      80,000,000          10,928            0.01
----------------------------------------------------------------------------------------------------------------
                                   U.S. Part 29 Small Rotorcraft Manufacturers
----------------------------------------------------------------------------------------------------------------
Erickson Air-Crane..............................             600      35,000,000          24,916            0.07
----------------------------------------------------------------------------------------------------------------

    As we expect only one of these companies to certificate a new 
rotorcraft in the next 10 years, only one will incur compliance costs. 
We estimated this compliance cost will be less that 0.2 percent of 
their total annual revenue.
    Thus, we determined that no small entity will incur a substantial 
economic impact in the form of higher annual costs as a result of this 
rule. Consequently, the FAA Administrator certifies that this final 
rule will not have a significant economic impact on a substantial 
number of small rotorcraft manufacturers.

Trade Impact Assessment 

    The Trade Agreements Act of 1979 (Pub. L. 96-39) prohibits Federal 
agencies from establishing any
---------------------------------------------------------------------------

    \5\ Uniform Annual Value discounted at 7% over 10-year period.
    \6\ Uniform Annual Value discounted at 7% over 10-year 
period.standards or engaging in related activities that create 
unnecessary obstacles to the foreign commerce of the United States. 
Legitimate domestic objectives, such as safety, are not considered 
unnecessary obstacles. The statute also requires consideration of 
international standards and, where appropriate, that these 
international standards be the basis for U.S. standards.

---------------------------------------------------------------------------

[[Page 10998]]

    The FAA has assessed the potential effect of this final rulemaking 
action and determined that it will reduce trade barriers by narrowing 
the differences between international and U.S. certification standards. 
Therefore, this final rule is in accord with the Trade Agreements Act.

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 
(adjusted annually for inflation) in any 1 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 $120.7 million in lieu of 
$100 million. This final rule does not contain such a mandate. The 
requirements of Title II do not apply.

Executive Order 13132, Federalism

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

Regulations Affecting Intrastate Aviation in Alaska

    Section 1205 of the FAA Reauthorization Act of 1996 (110 Stat. 
3213) requires the FAA, when modifying its regulations in a manner 
affecting intrastate aviation in Alaska, to consider the extent to 
which Alaska is not served by transportation modes other than aviation, 
and to establish appropriate regulatory distinctions. In the NPRM, we 
requested comments on whether the proposed rule should apply 
differently to intrastate operations in Alaska. We did not receive any 
comments, and we have determined, based on the administrative record of 
this rulemaking, that there is no need to make any regulatory 
distinctions applicable to intrastate aviation in Alaska.

Environmental Analysis

    FAA Order 1050.1E 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 312f and involves no extraordinary 
circumstances.

Regulations That Significantly Affect Energy Supply, Distribution, or 
Use

    The FAA has analyzed this final rule under Executive Order 13211, 
Actions Concerning Regulations that Significantly Affect Energy Supply, 
Distribution, or Use (May 18, 2001). We have determined that it is not 
a ``significant energy action'' under the executive order because it is 
not a ``significant regulatory action'' under Executive Order 12866, 
and it is not likely to have a significant adverse effect on the 
supply, distribution, or use of energy.

Availability of Rulemaking Documents

    You may obtain an electronic copy of rulemaking documents using the 
Internet by--
    1. Searching the Federal eRulemaking Portal (http://
www.regulations.gov);
    2. Visiting the FAA's Regulations and Policies Web page at http://
www.faa.gov/regulations--policies/; or
    3. Accessing the Government Printing Office's Web page at http://
www.gpoaccess.gov/fr/index.html.
    You may also obtain a copy 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. Make 
sure to identify the amendment number or docket number of this 
rulemaking.
    Anyone is able to search the electronic form of all comments 
received into any of our dockets by the name of the individual 
submitting the comment (or signing the comment, if submitted on behalf 
of an association, business, labor union, etc.). You may review DOT's 
complete Privacy Act statement in the Federal Register published on 
April 11, 2000 (Volume 65, Number 70; Pages 19477-78) or you may visit 
http://www.regulations.gov.

Small Business Regulatory Enforcement Fairness Act

    The Small Business Regulatory Enforcement Fairness Act (SBREFA) of 
1996 requires FAA to comply with small entity requests for information 
or advice about compliance with statutes and regulations within its 
jurisdiction. If you are a small entity and you have a question 
regarding this document, you may contact your local FAA official, or 
the person listed under the FOR FURTHER INFORMATION CONTACT heading at 
the beginning of the preamble. You can find out more about SBREFA on 
the Internet at http://www.faa.gov/regulations--policies/rulemaking/
sbre--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 Amendment

0
In consideration of the foregoing, the Federal Aviation Administration 
amends parts 27 and 29 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.  27.25 by adding the word ``weight'' after the word 
``maximum'' and removing the word ``or'' at the end of the sentence in 
paragraph (a)(1)(ii); removing the word ``and'' and adding the word 
``or'' in its place in paragraph (a)(1)(iii); and by adding paragraph 
(a)(1)(iv) to read as follows:

Sec.  27.25  Weight limits.

    (a) * * *
    (1) * * *
    (iv) The highest weight in which the provisions of Sec. Sec.  27.79 
or 27.143(c)(1), or combinations thereof, are demonstrated if the 
weights and operating conditions (altitude and temperature) prescribed 
by those requirements cannot be met; and
* * * * *
0
3. Re-designate Sec.  27.73 as new Sec.  27.49 and revise to read as 
follows:

Sec.  27.49  Performance at minimum operating speed.

    (a) For helicopters--
    (1) The hovering ceiling must be determined over the ranges of 
weight, altitude, and temperature for which certification is requested, 
with--
    (i) Takeoff power;
    (ii) The landing gear extended; and

[[Page 10999]]

    (iii) The helicopter in-ground effect at a height consistent with 
normal takeoff procedures; and
    (2) The hovering ceiling determined under paragraph (a)(1) of this 
section must be at least--
    (i) For reciprocating engine powered helicopters, 4,000 feet at 
maximum weight with a standard atmosphere;
    (ii) For turbine engine powered helicopters, 2,500 feet pressure 
altitude at maximum weight at a temperature of standard plus 22 [deg]C 
(standard plus 40 [deg]F).
    (3) The out-of-ground effect hovering performance must be 
determined over the ranges of weight, altitude, and temperature for 
which certification is requested, using takeoff power.
    (b) For rotorcraft other than helicopters, the steady rate of climb 
at the minimum operating speed must be determined over the ranges of 
weight, altitude, and temperature for which certification is requested, 
with--
    (1) Takeoff power; and
    (2) The landing gear extended.

0
4. Revise Sec.  27.51 to read as follows:

Sec.  27.51  Takeoff.

    The takeoff, with takeoff power and r.p.m. at the most critical 
center of gravity, and with weight from the maximum weight at sea level 
to the weight for which takeoff certification is requested for each 
altitude covered by this section--
    (a) May not require exceptional piloting skill or exceptionally 
favorable conditions throughout the ranges of altitude from standard 
sea level conditions to the maximum altitude for which takeoff and 
landing certification is requested, and
    (b) Must be made in such a manner that a landing can be made safely 
at any point along the flight path if an engine fails. This must be 
demonstrated up to the maximum altitude for which takeoff and landing 
certification is requested or 7,000 feet density altitude, whichever is 
less.

0
5. Revise the section heading of Sec.  27.71 to read as follows:

Sec.  27.71  Autorotation performance.

* * * * *

0
6. Revise Sec.  27.75(a) to read as follows:

Sec.  27.75  Landing.

    (a) The rotorcraft must be able to be landed with no excessive 
vertical acceleration, no tendency to bounce, nose over, ground loop, 
porpoise, or water loop, and without exceptional piloting skill or 
exceptionally favorable conditions, with--
    (1) Approach or autorotation speeds appropriate to the type of 
rotorcraft and selected by the applicant;
    (2) The approach and landing made with--
    (i) Power off, for single engine rotorcraft and entered from steady 
state autorotation; or
    (ii) One-engine inoperative (OEI) for multiengine rotorcraft, with 
each operating engine within approved operating limitations, and 
entered from an established OEI approach.
* * * * *

0
7. Re-designate Sec.  27.79 as new Sec.  27.87; revise the section 
heading; remove the word ``rotocraft'' and add in its place the word 
``rotorcraft'' in paragraph (b)(3); and revise paragraphs (a)(1), 
(a)(2) and (b)(2) to read as follows:

Sec.  27.87  Height-speed envelope.

    (a) * * *
    (1) Altitude, from standard sea level conditions to the maximum 
altitude capability of the rotorcraft, or 7000 feet density altitude, 
whichever is less; and
    (2) Weight, from the maximum weight at sea level to the weight 
selected by the applicant for each altitude covered by paragraph (a)(1) 
of this section. For helicopters, the weight at altitudes above sea 
level may not be less than the maximum weight or the highest weight 
allowing hovering out-of-ground effect, whichever is lower.
    (b) * * *
    (2) For multiengine helicopters, OEI (where engine isolation 
features ensure continued operation of the remaining engines), and the 
remaining engine(s) within approved limits and at the minimum installed 
specification power available for the most critical combination of 
approved ambient temperature and pressure altitude resulting in 7000 
feet density altitude or the maximum altitude capability of the 
helicopter, whichever is less, and
* * * * *

0
8. Amend Sec.  27.143 by revising paragraph (a)(2)(v); re-designating 
paragraphs (d) and (e) as paragraphs (e) and (f) respectively; revising 
paragraphs (b)(4) and (c); and adding a new paragraph (d) to read as 
follows:

Sec.  27.143  Controllability and maneuverability.

    (a) * * *
    (2) * * *
    (v) Autorotation;
* * * * *
    (b) * * *
    (4) Power off (except for helicopters demonstrating compliance with 
paragraph (f) of this section) and power on.
    (c) Wind velocities from zero to at least 17 knots, from all 
azimuths, must be established in which the rotorcraft can be operated 
without loss of control on or near the ground in any maneuver 
appropriate to the type (such as crosswind takeoffs, sideward flight, 
and rearward flight)--
    (1) With altitude, from standard sea level conditions to the 
maximum takeoff and landing altitude capability of the rotorcraft or 
7000 feet density altitude, whichever is less; with--
    (i) Critical Weight;
    (ii) Critical center of gravity;
    (iii) Critical rotor r.p.m.;
    (2) For takeoff and landing altitudes above 7000 feet density 
altitude with-
    (i) Weight selected by the applicant;
    (ii) Critical center of gravity; and
    (iii) Critical rotor r.p.m.
    (d) Wind velocities from zero to at least 17 knots, from all 
azimuths, must be established in which the rotorcraft can be operated 
without loss of control out-of-ground-effect, with--
    (1) Weight selected by the applicant;
    (2) Critical center of gravity;
    (3) Rotor r.p.m. selected by the applicant; and
    (4) Altitude, from standard sea level conditions to the maximum 
takeoff and landing altitude capability of the rotorcraft.
* * * * *

0
9. Amend Sec.  27.173 by removing the words ``a speed'' in the two 
places in paragraph (a) and adding the words ``an airspeed'' in both 
their places; removing paragraph (c); and revising paragraph (b) to 
read as follows:

Sec.  27.173  Static longitudinal stability.

* * * * *
    (b) Throughout the full range of altitude for which certification 
is requested, with the throttle and collective pitch held constant 
during the maneuvers specified in Sec.  27.175(a) through (d), the 
slope of the control position versus airspeed curve must be positive. 
However, in limited flight conditions or modes of operation determined 
by the Administrator to be acceptable, the slope of the control 
position versus airspeed curve may be neutral or negative if the 
rotorcraft possesses flight characteristics that allow the pilot to 
maintain airspeed within 5 knots of the desired trim 
airspeed without exceptional piloting skill or alertness.

0
10. Amend Sec.  27.175 by removing paragraph (d); revising the 
introductory text paragraphs (a) and (b); revising paragraphs (b)(3) 
and (b)(5); re-designating paragraph (c) as (d) and

[[Page 11000]]

revising re-designated paragraph (d); and adding a new paragraph (c) to 
read as follows:

Sec.  27.175  Demonstration of static longitudinal stability.

    (a) Climb. Static longitudinal stability must be shown in the climb 
condition at speeds from Vy - 10 kt to Vy + 10 kt with--
* * * * *
    (b) Cruise. Static longitudinal stability must be shown in the 
cruise condition at speeds from 0.8 VNE - 10 kt to 0.8 VNE + 10 kt or, 
if VH is less than 0.8 VNE, from VH -10 kt to VH + 10 kt, with--
* * * * *
    (3) Power for level flight at 0.8 VNE or VH, whichever is less;
* * * * *
    (5) The rotorcraft trimmed at 0.8 VNE or VH, whichever is less.
    (c) VNE. Static longitudinal stability must be shown at speeds from 
VNE - 20 kt to VNE with--
    (1) Critical weight;
    (2) Critical center of gravity;
    (3) Power required for level flight at VNE -10 kt or maximum 
continuous power, whichever is less;
    (4) The landing gear retracted; and
    (5) The rotorcraft trimmed at VNE - 10 kt.
    (d) Autorotation. Static longitudinal stability must be shown in 
autorotation at--
    (1) Airspeeds from the minimum rate of descent airspeed-10 kt to 
the minimum rate of descent airspeed + 10 kt, with--
    (i) Critical weight;
    (ii) Critical center of gravity;
    (iii) The landing gear extended; and
    (iv) The rotorcraft trimmed at the minimum rate of descent 
airspeed.
    (2) Airspeeds from best angle-of-glide airspeed-10 kt to the best 
angle-of-glide airspeed + 10 kt, with--
    (i) Critical weight;
    (ii) Critical center of gravity;
    (iii) The landing gear retracted; and
    (iv) The rotorcraft trimmed at the best angle-of-glide airspeed.
* * * * *
0
11. Revise Sec.  27.177 to read as follows:

Sec.  27.177  Static directional stability.

    (a) The directional controls must operate in such a manner that the 
sense and direction of motion of the rotorcraft following control 
displacement are in the direction of the pedal motion with the throttle 
and collective controls held constant at the trim conditions specified 
in Sec.  27.175(a), (b), and (c). Sideslip angles must increase with 
steadily increasing directional control deflection for sideslip angles 
up to the lesser of--
    (1) 25 degrees from trim at a speed of 15 knots less 
than the speed for minimum rate of descent varying linearly to 10 degrees from trim at VNE;
    (2) The steady state sideslip angles established by Sec.  27.351;
    (3) A sideslip angle selected by the applicant, which corresponds 
to a sideforce of at least 0.1g; or
    (4) The sideslip angle attained by maximum directional control 
input.
    (b) Sufficient cues must accompany the sideslip to alert the pilot 
when the aircraft is approaching the sideslip limits.
    (c) During the maneuver specified in paragraph (a) of this section, 
the sideslip angle versus directional control position curve may have a 
negative slope within a small range of angles around trim, provided the 
desired heading can be maintained without exceptional piloting skill or 
alertness.

0
12. Amend Sec.  27.903 by adding a new paragraph (d) to read as 
follows:

Sec.  27.903  Engines.

* * * * *
    (d) Restart capability: A means to restart any engine in flight 
must be provided.
    (1) Except for the in-flight shutdown of all engines, engine 
restart capability must be demonstrated throughout a flight envelope 
for the rotorcraft.
    (2) Following the in-flight shutdown of all engines, in-flight 
engine restart capability must be provided.

0
13. Amend Sec.  27.1587 by removing paragraphs (b)(1)(i) and 
(b)(1)(ii), and revising the introductory text of paragraph (a) and 
paragraphs (a)(2)(i) and (a)(2)(ii) to read as follows:

Sec.  27.1587  Performance information.

    (a) The Rotorcraft Flight Manual must contain the following 
information, determined in accordance with Sec. Sec.  27.49 through 
27.79 and 27.143(c) and (d):
* * * * *
    (2) * * *
    (i) The steady rates of climb and descent, in-ground effect and 
out-of-ground effect hovering ceilings, together with the corresponding 
airspeeds and other pertinent information including the calculated 
effects of altitude and temperatures;
    (ii) The maximum weight for each altitude and temperature condition 
at which the rotorcraft can safely hover in-ground effect and out-of-
ground effect in winds of not less than 17 knots from all azimuths. 
These data must be clearly referenced to the appropriate hover charts. 
In addition, if there are other combinations of weight, altitude and 
temperature for which performance information is provided and at which 
the rotorcraft cannot land and take off safely with the maximum wind 
value, those portions of the operating envelope and the appropriate 
safe wind conditions must be stated in the Rotorcraft Flight Manual;
* * * * *

0
14. Amend Appendix B to part 27 by revising paragraphs V(a) and VII(a) 
to read as follows:

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

* * * * *

V. Static Lateral Directional Stability

    (a) Static directional stability must be positive throughout the 
approved ranges of airspeed, power, and vertical speed. In straight 
and steady sideslips up to 10[deg] from trim, 
directional control position must increase without discontinuity 
with the angle of sideslip, except for a small range of sideslip 
angles around trim. At greater angles up to the maximum sideslip 
angle appropriate to the type, increased directional control 
position must produce an increased angle of sideslip. It must be 
possible to maintain balanced flight without exceptional pilot skill 
or alertness.
* * * * *

VII. Stability Augmentation System (SAS)

    (a) If a SAS is used, the reliability of the SAS must be related 
to the effects of its failure. Any SAS failure condition that would 
prevent continued safe flight and landing must be extremely 
improbable. It must be shown that, for any failure condition of the 
SAS that is not shown to be extremely improbable--
    (1) The helicopter is safely controllable when the failure or 
malfunction occurs at any speed or altitude within the approved IFR 
operating limitations; and
    (2) The overall flight characteristics of the helicopter allow 
for prolonged instrument flight without undue pilot effort. 
Additional unrelated probable failures affecting the control system 
must be considered. In addition--
    (i) The controllability and maneuverability requirements in 
Subpart B of this part must be met throughout a practical flight 
envelope;
    (ii) The flight control, trim, and dynamic stability 
characteristics must not be impaired below a level needed to allow 
continued safe flight and landing; and
    (iii) The static longitudinal and static directional stability 
requirements of Subpart B must be met throughout a practical flight 
envelope.
* * * * *

PART 29--AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT

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

[[Page 11001]]

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

0
16. Amend Sec.  29.25 by adding paragraph (a)(4) to read as follows:

Sec.  29.25  Weight limits.

    (a) * * *
    (4) For Category B rotorcraft with 9 or less passenger seats, the 
maximum weight, altitude, and temperature at which the rotorcraft can 
safely operate near the ground with the maximum wind velocity 
determined under Sec.  29.143(c) and may include other demonstrated 
wind velocities and azimuths. The operating envelopes must be stated in 
the Limitations section of the Rotorcraft Flight Manual.
* * * * *

0
17. Amend Sec.  29.143 by revising paragraph (a)(2)(v); re-designating 
paragraphs (d) and (e) as paragraphs (e) and (f) respectively; revising 
paragraphs (b)(4) and (c); and adding a new paragraph (d) to read as 
follows:

Sec.  29.143  Controllability and maneuverability.

    (a) * * *
    (2) * * *
    (v) Autorotation; and
* * * * *
    (b) * * *
    (4) Power off (except for helicopters demonstrating compliance with 
paragraph (f) of this section) and power on.
    (c) Wind velocities from zero to at least 17 knots, from all 
azimuths, must be established in which the rotorcraft can be operated 
without loss of control on or near the ground in any maneuver 
appropriate to the type (such as crosswind takeoffs, sideward flight, 
and rearward flight), with--
    (1) Critical weight;
    (2) Critical center of gravity;
    (3) Critical rotor r.p.m.; and
    (4) Altitude, from standard sea level conditions to the maximum 
takeoff and landing altitude capability of the rotorcraft.
    (d) Wind velocities from zero to at least 17 knots, from all 
azimuths, must be established in which the rotorcraft can be operated 
without loss of control out-of-ground effect, with--
    (1) Weight selected by the applicant;
    (2) Critical center of gravity;
    (3) Rotor r.p.m. selected by the applicant; and
    (4) Altitude, from standard sea level conditions to the maximum 
takeoff and landing altitude capability of the rotorcraft.
* * * * *

0
18. Amend Sec.  29.173 by removing the words ``a speed'' in the two 
places it appears in paragraph (a) and adding the words ``an airspeed'' 
in their places; removing paragraph (c); and revising paragraph (b) to 
read as follows:

Sec.  29.173  Static longitudinal stability.

* * * * *
    (b) Throughout the full range of altitude for which certification 
is requested, with the throttle and collective pitch held constant 
during the maneuvers specified in Sec.  29.175(a) through (d), the 
slope of the control position versus airspeed curve must be positive. 
However, in limited flight conditions or modes of operation determined 
by the Administrator to be acceptable, the slope of the control 
position versus airspeed curve may be neutral or negative if the 
rotorcraft possesses flight characteristics that allow the pilot to 
maintain airspeed within 5 knots of the desired trim 
airspeed without exceptional piloting skill or alertness.

0
19. Revise Sec.  29.175 to read as follows:

Sec.  29.175  Demonstration of static longitudinal stability.

    (a) Climb. Static longitudinal stability must be shown in the climb 
condition at speeds from Vy - 10 kt to Vy + 10 kt with--
    (1) Critical weight;
    (2) Critical center of gravity;
    (3) Maximum continuous power;
    (4) The landing gear retracted; and
    (5) The rotorcraft trimmed at Vy.
    (b) Cruise. Static longitudinal stability must be shown in the 
cruise condition at speeds from 0.8 VNE-10 kt to 0.8 
VNE + 10 kt or, if VH is less than 0.8 
VNE, from VH - 10 kt to VH + 10 kt, with--
    (1) Critical weight;
    (2) Critical center of gravity;
    (3) Power for level flight at 0.8 VNE or VH, 
whichever is less;
    (4) The landing gear retracted; and
    (5) The rotorcraft trimmed at 0.8 VNE or VH, 
whichever is less.
    (c) VNE. Static longitudinal stability must be shown at speeds from 
VNE - 20 kt to VNE with--
    (1) Critical weight;
    (2) Critical center of gravity;
    (3) Power required for level flight at VNE - 10 kt or maximum 
continuous power, whichever is less;
    (4) The landing gear retracted; and
    (5) The rotorcraft trimmed at VNE - 10 kt.
    (d) Autorotation. Static longitudinal stability must be shown in 
autorotation at--
    (1) Airspeeds from the minimum rate of descent airspeed - 10 kt to 
the minimum rate of descent airspeed + 10 kt, with--
    (i) Critical weight;
    (ii) Critical center of gravity;
    (iii) The landing gear extended; and
    (iv) The rotorcraft trimmed at the minimum rate of descent 
airspeed.
    (2) Airspeeds from the best angle-of-glide airspeed - 10kt to the 
best angle-of-glide airspeed + 10kt, with--
    (i) Critical weight;
    (ii) Critical center of gravity;
    (iii) The landing gear retracted; and
    (iv) The rotorcraft trimmed at the best angle-of-glide airspeed.

0
20. Revise Sec.  29.177 to read as follows:

Sec.  29.177  Static directional stability.

    (a) The directional controls must operate in such a manner that the 
sense and direction of motion of the rotorcraft following control 
displacement are in the direction of the pedal motion with throttle and 
collective controls held constant at the trim conditions specified in 
Sec.  29.175(a), (b), (c), and (d). Sideslip angles must increase with 
steadily increasing directional control deflection for sideslip angles 
up to the lesser of--
    (1) 25 degrees from trim at a speed of 15 knots less 
than the speed for minimum rate of descent varying linearly to 10 degrees from trim at VNE;
    (2) The steady-state sideslip angles established by Sec.  29.351;
    (3) A sideslip angle selected by the applicant, which corresponds 
to a sideforce of at least 0.1g; or
    (4) The sideslip angle attained by maximum directional control 
input.
    (b) Sufficient cues must accompany the sideslip to alert the pilot 
when approaching sideslip limits.
    (c) During the maneuver specified in paragraph (a) of this section, 
the sideslip angle versus directional control position curve may have a 
negative slope within a small range of angles around trim, provided the 
desired heading can be maintained without exceptional piloting skill or 
alertness.

0
21. Amend Sec.  29.1587 by revising paragraph (a)(7), (b)(2), and 
(b)(8) to read as follows:

Sec.  29.1587  Performance information.

* * * * *
    (a) * * *
    (7) Out-of-ground effect hover performance determined under Sec.  
29.49 and the maximum weight for each altitude and temperature 
condition at which the rotorcraft can safely hover out-of-ground effect 
in winds of not less than 17 knots from all azimuths. These data must 
be clearly referenced to the appropriate hover charts.
    (b) * * *
    (2) The steady rates of climb and in-ground-effect hovering 
ceiling, together with the corresponding airspeeds and other pertinent 
information, including

[[Page 11002]]

the calculated effects of altitude and temperature;
* * * * *
    (8) Out-of-ground effect hover performance determined under Sec.  
29.49 and the maximum safe wind demonstrated under the ambient 
conditions for data presented. In addition, the maximum weight for each 
altitude and temperature condition at which the rotorcraft can safely 
hover out-of-ground-effect in winds of not less than 17 knots from all 
azimuths. These data must be clearly referenced to the appropriate 
hover charts; and
* * * * *
0
22. Amend Appendix B to Part 29 in paragraph V(b) by removing the word 
``cycle'' and adding the word ``cyclic'' in its place; and by revising 
paragraphs V(a) and VII(a) to read as follows:

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

* * * * *

V. Static Lateral Directional Stability

    (a) Static directional stability must be positive throughout the 
approved ranges of airspeed, power, and vertical speed. In straight 
and steady sideslips up to 10[deg] from trim, 
directional control position must increase without discontinuity 
with the angle of sideslip, except for a small range of sideslip 
angles around trim. At greater angles up to the maximum sideslip 
angle appropriate to the type, increased directional control 
position must produce an increased angle of sideslip. It must be 
possible to maintain balanced flight without exceptional pilot skill 
or alertness.
* * * * *

VII. Stability Augmentation System (SAS)

    (a) If a SAS is used, the reliability of the SAS must be related 
to the effects of its failure. Any SAS failure condition that would 
prevent continued safe flight and landing must be extremely 
improbable. It must be shown that, for any failure condition of the 
SAS that is not shown to be extremely improbable--
    (1) The helicopter is safely controllable when the failure or 
malfunction occurs at any speed or altitude within the approved IFR 
operating limitations; and
    (2) The overall flight characteristics of the helicopter allow 
for prolonged instrument flight without undue pilot effort. 
Additional unrelated probable failures affecting the control system 
must be considered. In addition--
    (i) The controllability and maneuverability requirements in 
Subpart B must be met throughout a practical flight envelope;
    (ii) The flight control, trim, and dynamic stability 
characteristics must not be impaired below a level needed to allow 
continued safe flight and landing;
    (iii) For Category A helicopters, the dynamic stability 
requirements of Subpart B must also be met throughout a practical 
flight envelope; and
    (iv) The static longitudinal and static directional stability 
requirements of Subpart B must be met throughout a practical flight 
envelope.
* * * * *

    Issued in Washington, DC, on February 20, 2008.
Robert A. Sturgell,
Acting Administrator.
 [FR Doc. E8-3817 Filed 2-28-08; 8:45 am]

BILLING CODE 4910-13-P