Performance and Handling Qualities Requirements for Rotorcraft, 42222-42232 [E6-11726]

Agencies

• Federal Aviation Administration
• DEPARTMENT OF TRANSPORTATION

[Federal Register Volume 71, Number 142 (Tuesday, July 25, 2006)]
[Proposed Rules]
[Pages 42222-42232]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E6-11726]



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Part III





Department of Transportation





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Federal Aviation Administration



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14 CFR Parts 27 and 29



Performance and Handling Qualities Requirements for Rotorcraft; 
Proposed Rule

Federal Register / Vol. 71, No. 142 / Tuesday, July 25, 2006 / 
Proposed Rules

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Parts 27 and 29

[Docket No. FAA-2006-25414; Notice No. 06-11]
RIN 2120-AH87


Performance and Handling Qualities Requirements for Rotorcraft

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA is proposing 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 would 
enhance the safety standards for performance and handling qualities to 
reflect the evolution of rotorcraft capabilities.

DATES: Send your comments on or before October 23, 2006.

ADDRESSES: You may send comments [identified by Docket Number FAA-2006-
25414] using any of the following methods:
     DOT Docket Web site: Go to https://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to https://
www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590-0001.
     Fax: 1-202-493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For more information on the rulemaking process, see the SUPPLEMENTARY 
INFORMATION section of this document.
    Privacy: We will post all comments we receive, without change, to 
https://dms.dot.gov, including any personal information you provide. For 
more information, see the Privacy Act discussion in the SUPPLEMENTARY 
INFORMATION section of this document.
    Docket: To read background documents or comments received, go to 
https://dms.dot.gov at any time or to Room PL-401 on the plaza level of 
the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Jeff Trang, Rotorcraft Standards 
Staff, Rotorcraft Directorate, ASW-110, Federal Aviation 
Administration, Fort Worth, Texas 76193-0110, telephone number (817) 
222-5135; facsimile (817) 222-5961, e-mail jeff.trang@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites interested persons to participate in this 
rulemaking by submitting written comments, data, or views. We also 
invite comments relating to the economic, environmental, energy, or 
federalism impacts that might result from adopting the proposals in 
this document. The most helpful comments reference a specific portion 
of the proposal, explain the reason for any recommended change, and 
include supporting data. We ask that you send us two copies of written 
comments.
    We will file in the docket all comments we receive, as well as a 
report summarizing each substantive public contact with FAA personnel 
concerning this proposed rulemaking. The docket is available for public 
inspection before and after the comment closing date. If you wish to 
review the docket in person, go to the address in the ADDRESSES section 
of this preamble between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. You may also review the docket using the 
Internet at the web address in the ADDRESSES section.
    Privacy Act: Using the search function of our docket Web site, 
anyone can find and read the comments received into any of our dockets, 
including the name of the individual sending the comment (or signing 
the comment 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 (65 FR 19477-78) or you may visit 
https://dms.dot.gov.
    Before acting on this proposal, we will consider all comments we 
receive on or before the closing date for comments. We will consider 
comments filed late if it is possible to do so without incurring 
expense or delay. We may change this proposal in light of the comments 
we receive.
    If you want the FAA to acknowledge receipt of your comments on this 
proposal, include with your comments a pre-addressed, stamped postcard 
on which the docket number appears. We will stamp the date on the 
postcard and mail it to you.

Proprietary or Confidential Business Information

    Do not file in the docket information that you consider to be 
proprietary or confidential business information. Send or deliver this 
information directly to the person identified in the FOR FURTHER 
INFORMATION CONTACT section of this document. You must mark the 
information that you consider proprietary or confidential. If you send 
the information on a disk or CD-ROM, mark the outside of the disk or 
CD-ROM and also identify electronically within the disk or CD-ROM the 
specific information that is proprietary or confidential.
    Under 14 CFR 11.35(b), when we are aware of proprietary information 
filed with a comment, we do not place it in the docket. We hold it in a 
separate file to which the public does not have access, and place a 
note in the docket that we have received it. If we receive a request to 
examine or copy this information, we treat it as any other request 
under the Freedom of Information Act (5 U.S.C. 552). We process such a 
request under the DOT procedures found in 49 CFR part 7.

Availability of Rulemaking Documents

    You can get an electronic copy using the Internet by:
    (1) Searching the Department of Transportation's electronic Docket 
Management System (DMS) Web page (https://dms.dot.gov/search);
    (2) Visiting the FAA's Regulations and Policies Web page at https://
www.faa.gov/regulations_policies/; or
    (3) Accessing the Government Printing Office's Web page at https://
www.gpoaccess.gov/fr/.
    You can also get 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 docket number, notice number, or amendment number 
of this rulemaking.

Authority for This Rulemaking

    The FAA's authority to issue rules regarding 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

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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, air 
agency 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 these authorities 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

Statement of the Problem

    Due to technological advances in design and operational trends in 
normal and transport rotorcraft performance and handling qualities, the 
FAA is proposing new and revised airworthiness standards. Some current 
part 27 and 29 regulations do not reflect, in some cases, safety levels 
attainable by modern rotorcraft, and FAA-approved equivalent level of 
safety findings.

History

    It has been more than 20 years since the last major promulgation of 
rules that address the performance and handling qualities of rotorcraft 
(Amendments 29-24 and 27-21, 49 FR 44433 and 49 FR 44436, November 6, 
1984). Since then, the FAA has developed policy and procedures that 
address certain aspects of these requirements to make the parts 27 and 
29 rules workable within the framework of later rotorcraft designs and 
operational needs. In addition, most manufacturers have routinely 
exceeded some of the minimum performance requirements in part 27 and 29 
of Title 14 of the Code of Federal Regulation (CFR) to meet customer 
needs.
    After the publication of the first issue of the Joint Aviation 
Regulations (JAR) for parts 27 and 29, which closely mirrored 14 CFR 
part 29 at amendment 31 and 14 CFR part 27 at amendment 27, the 
European Joint Aviation Authorities (JAA) Helicopter Airworthiness 
Study Group (HASG) and the FAA agreed to form a specialist subgroup to 
review proposals on flight matters that were not incorporated during 
promulgation of the JAR. This subgroup consisted of representatives of 
the JAA, Association of European des Constructeurs de Material 
Aerospatiale (AECMA), Aerospace Industries Association of America 
(AIA), and the FAA.
    The subgroup first met in January 1994, and presented their 
findings to the HASG and the FAA in May 1994. The FAA announced the 
formation of the Performance and Handling Qualities Requirements 
Harmonization Working Group (PHQHWG) in the Federal Register (60 FR 
4220, January 20, 1995) to act on the recommendation presented to the 
HASG and the FAA by the specialist subgroup. The PHQHWG was charged 
with recommending to the Aviaiton Rulemaking Advisory Committee (ARAC) 
new or revised standards for flight-test procedures and requirements. 
The PHQHWG was tasked 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 included representatives that expressed an interest by 
responding to the notice the FAA published in the Federal Register. The 
PHQHWG included representatives from the AIA, the AECMA, the European 
JAA, Transport Canada, and the FAA Rotorcraft Directorate. 
Additionally, the PHQHWG consulted representatives from the 
manufacturers of small rotorcraft. This broad participation is 
consistent with the FAA policy to involve all known interested parties 
as early as practicable in the rulemaking process. The PHQHWG first met 
in March 1995 and has subsequently met nine times.

General Discussion of the Proposals

    Using the report submitted to the HASG as a starting point, the 
PHQHWG agreed there was a need to update the rotorcraft performance and 
handling qualities standards. As the meetings progressed, the group 
evaluated additional internally generated proposals to change the 
performance and handling qualities requirements that were believed to 
be pertinent to the group's task. These proposals were either accepted 
or rejected on their merits and by consensus of the group. The group 
also came to a common understanding of some acceptable methods of 
compliance for the proposals as well as the current requirements, and 
appropriate Advisory Circular material was developed concurrently with 
this proposed rule.
    There was much discussion in the working group about the evolution 
of the Appendix B Instrument Flight Rules (IFR) flight characteristic 
requirements. Early IFR helicopters were developed using relatively 
simple analog systems consisting primarily of two or three-axis rate 
damping with, in some cases, attitude or heading hold features. Today, 
there are complex digital automatic flight control systems or flight 
management systems available with highly redundant system 
architectures. These highly complex systems may have enough redundancy 
or compensating features to allow system operating characteristics as 
well as acceptable aircraft handling qualities to be maintained in 
degraded modes of operation. Due to the difficulty of adequately 
addressing all the various elements of these complex systems and the 
associated flight characteristics, it was decided not to initiate parts 
27 and 29 rulemaking addressing these complex systems at this time, and 
that the certification requirements for these types of complex systems 
would be handled on a case-by-case basis within the current regulatory 
structure.

Section-by-Section Discussion of the Proposals

Section 27.25 Weight Limits

    Paragraph (a)(1)(iv) would be added to formalize the equivalent 
level of safety findings by establishing a maximum weight limit if the 
requirements in Sec.  27.79 or Sec.  27.143(c)(1) cannot be met. Some 
recent certifications of part 27 rotorcraft have required placing 
weight, altitude, and temperature limitations in the Rotorcraft Flight 
Manual (RFM) to achieve an equivalent level of safety with certain 
flight requirements. Specifically, the requirement for controllability 
near the ground while at maximum weight and 7,000 feet density altitude 
and the requirement to establish the height-speed envelope at maximum 
weight or the highest weight allowing for hover out-of-ground-effect 
(OGE) for altitudes above sea level are considered a minimum level of 
safety for normal category rotorcraft. If compliance with these minimum 
standards is reached, the resultant data is put in the flight manual as 
performance information. In some cases, an equivalent level of safety

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has been attained by prohibiting certain operations and including 
limitations in the RFM that reflect the actual capability of the 
rotorcraft.

Section 29.25 Weight Limits

    Amendments 29-21 (48 FR 4374, January 31, 1983) and 29-24 (49 FR 
44422, November 6, 1984) granted relief to certain operating 
limitations for Category B certificated rotorcraft with a passenger 
seating capacity of nine or less. These amendments stated that, for 
these rotorcraft, the hover controllability requirements of Sec.  
29.143(c) should not be operating limitations. However, these 
amendments did not specifically include language that would assure 
appropriate limitations are provided in the RFM. The FAA has determined 
that it is necessary to establish appropriate limitations to ensure 
safe aircraft operations within the demonstrated performance envelope 
of the helicopter. This proposed rule would 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 limited wind azimuths, become operating limitations.

New Sec.  27.49 Performance at Minimum Operating Speed (Formerly Sec.  
27.73)

    This proposed rule would redesignate Sec.  27.73 as Sec.  27.49 and 
add a requirement to determine the OGE hover performance. Installed 
engine power available on normal category helicopters has increased 
significantly since the promulgation of the original part 27 
requirement, particularly for hot-day and high-altitude conditions. As 
a result, OGE helicopter operations once limited to special missions 
have become common. Most manufacturers present OGE hover performance 
data in approved flight manuals, although these data are not currently 
required. This change would mandate the current industry practice and 
require that OGE hover data be determined throughout the range of 
weights, altitudes, and temperatures.

Section 27.51 Takeoff

    The proposed rule would revise the wording of Sec.  27.51 to 
recognize that the most critical center-of-gravity (CG) may not be the 
extreme forward CG, and would require that tests be performed at the 
most critical CG configuration and at the maximum weight for which 
takeoff certification is requested. The current standard requires that 
tests be performed at the extreme forward CG and at a weight selected 
by the applicant for altitudes above sea level. Although for most 
rotorcraft the extreme forward CG is most critical, this may not be 
true for all rotorcraft, and the proposed language would provide for 
such possibilities. This change to Sec.  27.51 more clearly states the 
intent of the current rule, which is to demonstrate engine failure 
along the takeoff flight path at the weight for which takeoff data are 
provided. 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, has been clarified to 
explicitly state that the altitudes cited in the requirement are 
density altitudes.

Section 27.75 Landing

    The proposed rule would revise Sec.  27.75(a) to state the required 
flight condition in more traditional rotorcraft terminology. Included 
in this revision to Sec.  27.75(a) is the requirement for multi-engine 
helicopters to demonstrate landings with one engine inoperative and 
initiated from an established approach. The proposed rule would also 
make a minor revision in the text of paragraph (a) of this section by 
replacing the word ``glide'' with ``autorotation.''

Section 27.79 Limiting Height-Speed Envelope

    The proposed rule would revise Sec.  27.79(a)(1) to include the 
words ``density altitude'' after ``7000 feet.'' The proposed rule would 
also revise Sec.  27.79(a)(2) by removing the word ``lesser'' from the 
first sentence. This change reflects that current OGE weights for 
helicopters are not necessarily less than the maximum weight at sea 
level. Additionally, in Sec.  27.79(b)(2), the term ``greatest power'' 
is removed and replaced 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 engine power after it is corrected 
for installation losses. The specific text in the proposed rule of the 
ambient conditions that define the engine power to be used during the 
compliance demonstration is consistent with existing advisory material 
and current industry practice.

Section 27.143 Controllability and Maneuverability

    This proposed rule would revise Sec.  27.143(a)(2)(v) to replace 
the word ``glide'' with ``autorotation.'' This minor change does not 
affect the method of compliance but states the required flight 
condition in more traditional rotorcraft terminology.
    This proposed rule would re-designate Sec.  27.143(c) paragraphs 
(1) through (4). Paragraph (4) would become paragraph (1) and 
paragraphs (1), (2), and (3) would become paragraphs (i), (ii), and 
(iii). Paragraph (c) in Sec.  27.143 is rewritten 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. The 
current part 27 rule could lead some applicants to conclude that only a 
17-knots controllability data point must be considered. That was not 
the intent of the current part 27 requirement. The most critical speed 
may be less than 17 knots. Additionally, the altitude requirement is 
clarified with the addition of the words ``density altitude.''
    Section 27.143(c)(2) is revised to require that controllability be 
determined at altitudes above 7,000 feet density altitude if takeoff 
and landing data are scheduled above that altitude. Currently, no 
requirement exists to determine controllability above 7,000 feet, even 
though takeoff and landing data may be presented above that altitude. 
With the advent of lighter and more powerful engines, it is not 
uncommon for rotorcraft to operate at altitudes that, until recently, 
were limited to a small number of rotorcraft performing very 
specialized operations. Since more rotorcraft are operating at these 
altitudes, safety dictates that controllability and maneuverability be 
determined above 7,000 feet.
    The proposed rule would add Sec.  27.143(d) to require the 
determination of controllability for wind velocities from zero to at 
least 17 knots OGE at weights selected by the applicant. Operations in 
support of law enforcement, search and rescue, and media coverage are 
often performed in such a manner that the rotorcraft performance in 
rearward or quartering flight is important in accomplishing the 
mission. This new requirement in Sec.  27.143(d), in conjunction with 
the proposed OGE hover requirement of Sec.  27.49, would increase the 
level of safety by requiring additional performance information.

Section 29.143 Controllability and Maneuverability

    The proposed rule would revise Sec.  29.143(a)(2)(v) to replace the 
word ``glide'' with ``autorotation.'' This minor change does not affect 
the method of compliance but states the required flight condition in 
more traditional rotorcraft terminology.
    Paragraph (c) in section Sec.  29.143 would be rewritten to clarify 
that

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controllability on or near the ground must be demonstrated throughout a 
range of speeds from zero to at least 17 knots. The current part 29 
rule could lead some applicants to the conclusion that only a 17-knot 
controllability data point must be considered when, in fact, the most 
critical speed may be less than 17 knots. This proposed rule would add 
paragraph (c)(4) to Sec.  29.143 to explicitly require that 
controllability be determined for wind velocities up to at least 17 
knots, at an altitude from standard sea level conditions to the maximum 
takeoff and landing altitude capability of the rotorcraft. This 
proposed rule reflects current practice.
    This proposed rule would add paragraph (d) to Sec.  29.143 to 
require that controllability be determined for wind velocities up to at 
least 17 knots OGE at weights selected by the applicant. Today, 
operations in support of law enforcement, search and rescue, and media 
coverage will often be performed in such a manner that the rotorcraft 
performance in rearward or quartering flight are of a safety concern.

Sections 27.173 and 29.173 Static Longitudinal Stability

    A minor clarification change is proposed to paragraph (a) in 
Sec. Sec.  27.173 and 29.173 to change ``a speed'' to ``an airspeed.'' 
Paragraph (b) would be combined with paragraph (c) in Sec. Sec.  27.173 
and 29.173 to allow neutral or negative static stability in limited 
areas of the flight envelope, if adequate compensating characteristics 
are present and the pilot can maintain airspeed within 5 knots of the 
desired trim speed during the conditions specified in Sec. Sec.  27.175 
and 29.175.
    The ability to maintain appropriate airspeed control during other 
flight conditions would be tested under Sec. Sec.  27.143 and 29.143. 
Neutral or negative static longitudinal stability in limited flight 
domains has been allowed for numerous rotorcraft under equivalent level 
of safety findings when adequate compensating features have been 
present. The satisfactory experience gained with these equivalent 
safety findings has provided the basis for the proposed change. 
Historically, these limited flight domains have been encountered at the 
aft limit of the weight/CG envelopes during descent, or autorotation, 
or climb stability demonstrations. Historically, negative longitudinal 
control position gradient versus airspeed has generally been no more 
than 2 to 3 percent of the total control travel.
    Additionally, these proposals would delete the Sec. Sec.  27.173(c) 
and 29.173(c) requirements relating to the hover demonstration 
specified in the current Sec. Sec.  27.175(d) and 29.175(d). See 
additional discussion at Sec. Sec.  27.175 and 29.175.

Sections 27.175 and 29.175 Demonstration of Static Longitudinal 
Stability

    The proposals in paragraphs (a) and (b) would decrease the speed 
range about the specified trim speeds to more representative values 
than are currently contained in the rule. A new paragraph (c) would 
require an additional level flight demonstration point. The current 
paragraph (c) would be re-designated as paragraph (d), and the current 
paragraph (d) containing the hover demonstration would be deleted.
    Some current requirements in Sec. Sec.  27.175 and 29.175 are not 
appropriate for the newer generation of rotorcraft. When the current 
regulation was written, the cruise demonstration of 0.7 VH 
to 1.1 VH typically represented approximately a 30 knots 
speed variation for helicopters. Now, the cruise demonstration, between 
the maximum and the minimum speeds (1.1 VH and 0.7 
VH), can encompass such a large speed range that the trim 
point and end points actually represent completely different flight 
regimes rather than perturbations about a trim point in a given flight 
regime. For some modern helicopters with a never-exceed speed 
(VNE) in excess of 150 knots, the speed variation for the 
cruise demonstration could approach 60 knots, which makes the maneuver 
difficult to perform and does not represent a normal variation about a 
trim point. These proposals would reduce the speed range for the cruise 
demonstration to 10 knots about the specified trim point.
    An additional demonstration point at a trim airspeed of 
VNE-10 knots is proposed to maintain the data coverage over 
a speed range similar to that contained in the current Sec. Sec.  
27.175(b) and 29.175(b).
    For the demonstration in autorotation, the current requirement 
specifies that the rotorcraft be trimmed at speeds found necessary by 
the Administrator to demonstrate stability. The proposed rule would 
specify typically used trim speeds--minimum rate of descent and best 
angle of glide airspeeds--for the stability demonstration. The 
conditions required to develop these airspeeds are currently stated in 
Sec. Sec.  27.67, 27.71, 29.67 and 29.71. The proposed rule would also 
limit the speed range for demonstration to 10 knots from 
the trim points. The proposed new trim points and speed ranges may not 
encompass VNE in autorotation as explicitly required in 
current Sec. Sec.  27.175 and 29.175. The proposed trim points, 
however, provide data at the most likely operating conditions. 
Autorotation at VNE is typically a transient and dynamic 
flight condition that often places high workload demands on the pilot 
due primarily to maintaining rotor speed control and the desired flight 
path. During these dynamic conditions of autorotation at VNE 
that are evaluated under Sec. Sec.  27.143 and 29.143, longitudinal 
static stability is less important than in the more stabilized 
conditions as proposed.
    This proposed rule would delete the hover demonstration 
requirements of current Sec. Sec.  27.175(d) and 29.175(d). The 
requirement to demonstrate static longitudinal stability in a hover has 
been shown to be unnecessary since the proper sense and motion of 
controls during hover are evaluated as part of other required tests. 
The controllability and maneuverability requirements of Sec. Sec.  
27.143(a) and (c) and 29.143(a) and (c) adequately address the safety 
considerations during hover flight.

Sections 27.177 and 29.177 Static Directional Stability

    This proposed rule would revise Sec. Sec.  27.177 and 29.177 to 
change the demonstration criteria for static directional stability. The 
current part 27 and 29 rule contains general language and relies 
primarily on a pilot's subjective judgment that he is approaching the 
sideslip limit, which renders it difficult to make compliance 
determinations due to a lack of objective test criteria. The proposals 
would provide further objective criteria over which the directional 
stability characteristics of rotorcraft are evaluated. The proposed 
rule also allows for a minimal amount of negative stability around each 
trim point. This recognizes the characteristics exhibited by many 
rotorcraft that have some airflow blockage of the vertical fin or tail 
rotor at small sideslip angles. This minimal amount of negative 
stability does not materially affect the overall safety considerations 
of static directional stability.

Section 27.903 Engines

    This proposed rule would revise Sec.  27.903 to add a new paragraph 
(d) to require engine restart capability. A restart capability is a 
fundamental necessity for any aircraft to minimize the risk of a forced 
landing. A restart capability will enhance safety, even though it will 
not be useful in every case such as when there is engine damage or 
insufficient altitude to carry out the restart procedure. A study of

[[Page 42226]]

accident and incident data shows a large number of engine failures or 
flameouts on rotorcraft with a restart capability. A number of these 
incidents resulted in successful in-flight restarts following failure 
due to causes such as snow and ice ingestion, fuel contamination, or 
fuel mismanagement. The data related to the accident and incident 
engine failures or flameouts are contained in the Docket. The proposed 
text, taken directly from current Sec.  29.903(e), would require an in-
flight restart capability for both single-engine and multiengine 
rotorcraft. We intend that restart procedures be included in the RFM.

Section 27.1587 Performance Information

    Section 27.1587(a) would be revised to include a reference to new 
Sec.  27.49. Section 27.1587(a)(2)(i) and (ii) would be revised to 
specifically include requirements for presenting maximum safe winds for 
OGE operations established in the proposed Sec.  27.143. Section 
27.1587(b)(1)(i) and (ii) would be deleted. These two paragraphs were 
moved into Sec.  27.1585(a) by Amendment 27-21, and inadvertently left 
in from Sec.  27.1587.

Section 29.1587 Performance Information

    The proposal to revise Sec.  29.1587 would require new performance 
information be included in the RFM. Sections 29.1587(a)(7) and 
29.1587(b)(8) would be amended to include the requirements for 
presenting maximum safe winds for OGE operations.

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

    The proposed rule would amend paragraph (V)(a) to allow for a 
minimal amount of neutral or negative stability around trim and would 
replace the words ``in approximately constant proportion'' with 
``without discontinuity.'' This is intended to be a more objective 
standard that does not allow irregularity in the aircraft response to 
control input. Also, this is consistent with the change that is 
proposed in Sec.  27.177 of the VFR requirements that proposes more 
specific criteria to evaluate stability characteristics, but also 
recognizes a minimal amount of negative stability. Additionally, the 
proposed paragraph would require that the pilot be able to maintain the 
desired heading without exceptional skill or alertness. This proposed 
rule would also revise paragraph VII(a)(1) and VII(a)(2). This revision 
would reorganize the paragraphs and further specify the standards that 
must be met when considering a stability augmentation system failure.

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

    The proposed rule would amend paragraph (V)(a) to allow for a 
minimal amount of neutral or negative stability around trim and would 
replace the words ``in approximately constant proportion'' with 
``without discontinuity.'' This is intended to be a more objective 
standard that does not allow irregularity in the aircraft response to 
control input. Also, this is consistent with the change that is 
proposed in Sec.  29.177 of the VFR requirements that proposes more 
specific criteria to evaluate stability characteristics, but also 
recognizes a minimal amount of negative stability. Additionally, the 
proposed paragraph would require that the pilot be able to maintain the 
desired heading without exceptional skill or alertness. Lastly, in 
paragraph (V)(b)--the word ``cycle'' is replaced by the correct word, 
``cyclic.''
    This proposed rule would revise paragraphs VII(a)(1) and VII(a)(2). 
This change would reorganize the paragraphs and further specify the 
standards that must be met when considering a stability augmentation 
system failure.

Paperwork Reduction Act

    This proposal contains the following new information collection 
requirements. As required by the Paperwork Reduction Act of 1995 (44 
U.S.C. 3507(d)), the FAA has submitted the information requirements 
associated with this proposal to the Office of Management and Budget 
for review.
    Title: Performance and Handling Qualities Requirements for 
Rotorcraft.
    Summary: This proposal would revise the airworthiness standards for 
normal and transport category rotorcraft performance and handling 
qualities. This proposal would increase the current minimum safety 
standards to require compliance with certain current industry practices 
and FAA policies that result in higher safety standards, and would 
result in harmonized international standards. Proposed Sec. Sec.  
27.49(a)(3) and 27.143(d) require all applicants seeking certification 
for a normal category rotorcraft to determine out-of-ground effect 
performance data, and the proposed Sec.  27.1587 requires that 
performance data be provided to operators in the RFM that must be 
furnished with each rotorcraft. For those applicants seeking 
certification for a transport category rotorcraft, proposed Sec.  
29.143(d) requires that they determine additional out-of-ground effect 
performance data. Proposed Sec.  29.1587 requires that performance 
data, in addition to current Sec.  29.49 and other data, be provided to 
operators in the RFM.
    Use of: The required performance information would be determined 
during the certification process for various rotorcraft weights, 
altitudes, and temperatures and would be collected from rotorcraft 
certification applicants. This performance information would be 
inserted into the RFM and used by rotorcraft operators to determine 
whether their rotorcraft was capable of performing certain missions in 
their operating environment.
    Respondents (including number of): We anticipate an average of 4 
normal or transport category rotorcraft certification applicants every 
10 years would be required to determine this performance information 
and provide it to operators in each RFM. We anticipate 50 rotorcraft 
are delivered for each new certification and a RFM must be furnished 
with each rotorcraft.
    Frequency: The frequency of determining the performance data would 
depend on how often an applicant seeks the certification of a 
rotorcraft. We anticipate four new rotorcraft certifications each 10 
years. This performance data would be provided when the manufacturer 
delivers each rotorcraft to an operator. Based on industry responses, 
we anticipate 50 rotorcraft are delivered per certification, resulting 
in 50 manuals.
    Annual Burden Estimate: The performance data must be collected 
during each certification and disclosed in each RFM. Based on industry 
response, we anticipate that it would take 20 hours at $100 per hour to 
collect the performance data for four certifications every 10 years for 
an annual collection burden of $200.00 ($100 * (20/10)). We further 
anticipate 2 additional pages would be required to place the data in 
the RFM. We estimate an annual paperwork burden of 120 pages with an 
annual reproduction cost of $6.00. Therefore, the estimated total 
annual cost burden of the additional paperwork for this proposed rule 
would be $206.00.
    The agency is soliciting comments to--
    (1) Evaluate whether the proposed information requirement is 
necessary for the proper performance of the functions of the agency, 
including whether the information will have practical utility;
    (2) Evaluate the accuracy of the agency's estimate of the burden;

[[Page 42227]]

    (3) Enhance the quality, utility, and clarity of the information to 
be collected; and
    (4) Minimize the burden of the collection of information on those 
who are to respond, including through the use of appropriate automated, 
electronic, mechanical, or other technological collection techniques or 
other forms of information technology.
    Individuals and organizations may submit comments on the 
information collection requirement by September 25, 2006, and should 
direct them to the address listed in the ADDRESSES section of this 
document. Comments also should be submitted to the Office of 
Information and Regulatory Affairs, OMB, New Executive Building, Room 
10202, 725 17th Street, NW., Washington, DC 20053, Attention: Desk 
Officer for FAA.
    According to the 1995 amendments to the Paperwork Reduction Act (5 
CFR 1320.8(b)(3)(vi)), an agency may not collect or sponsor the 
collection of information, nor may it impose an information collection 
requirement unless it displays a currently valid OMB control number. 
The OMB control number for this information collection will be 
published in the Federal Register, after the Office of Management and 
Budget approves it.

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 proposed regulations.

Executive Order 12866, DOT Regulatory Policies and Procedures, Economic 
Assessment, Regulatory Flexibility Determination, 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 proposed 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 proposed 
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) would not have a 
significant economic impact on a substantial number of small entities; 
(5) would not have a significant effect on international trade; and (6) 
would not impose an unfunded mandate on state, local, or tribal 
governments, or on the private sector by exceeding the threshold 
identified above. These analyses are summarized below.

Total Benefits and Costs of This Rulemaking

    The estimated cost of this proposed 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 those rotorcraft.

Our Cost Assumptions and Sources of Information

     Discount rate--7%.
     Period of analysis--10 years.\1\
---------------------------------------------------------------------------

    \1\ The 10-year analysis period covers our assumption that 
manufacturers will seek new certification 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 Rulemaking

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

Costs of This Rulemaking

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

Regulatory Flexibility Determination

    The Regulatory Flexibility Act of 1980 (Pub. L. 96-354) (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 consider flexible regulatory proposals, to explain the rationale for 
their actions, and to solicit comments. The RFA covers a wide-range of 
small entities, including small businesses, not-for-profit 
organizations and small governmental jurisdictions.
    Agencies must perform a review to determine whether a rule will 
have a significant economic impact on a substantial number of small 
entities. If the agency determines that it will, the agency must 
prepare a regulatory flexibility analysis as described in the RFA.
    However, if an agency determines that a proposed or final rule is 
not expected to have a significant economic impact on a substantial 
number of small entities, section 605(b) of the 1980 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.
    We use the Small Business Administration (SBA) guideline of 1,500 
employees or less per firm as the criterion for the determination of a

[[Page 42228]]

small business in commercial air service.\2\
---------------------------------------------------------------------------

    \2\ 13 CFR part 121.201, Size Standards Used to Define Small 
Business Concerns, Section 48-49 Transportation, Subsector 481 Air 
Transportation.
---------------------------------------------------------------------------

    In order to determine if the proposed 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, 
was tabulated.
    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 these businesses, after eliminating those with more 
than 1,500 employees and subsidiaries of larger businesses. An example 
of a subsidiary business is Bell Helicopter, which is a subsidiary of 
Textron, Inc.
    This methodology resulted in the following list of 6 U.S. part 27 
rotorcraft manufactures with less than 1,500 employees. None of the 
part 29 rotorcraft manufacturers has 1,500 or fewer employees.

------------------------------------------------------------------------
              U.S. rotorcraft manufactures                  Employment
------------------------------------------------------------------------
Hiller Aircraft Corp....................................              35
Brantly Helicopter Industry.............................              35
Enstrom Helicopter Corporation..........................             100
Schweizer Aircraft Corporation..........................             400
Erickson Air-Crane......................................             500
Robinson Helicopter Company, Inc........................             700
------------------------------------------------------------------------

    The FAA expects that one large firm and one small firm will seek 
certification of a new part 27 normal category rotorcraft over the next 
ten years. Although most of the proposed requirements intended to 
revise the flight certification requirements are current industry 
standard 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 
Rotorcraft Flight Manual (RFM). Sections 27.173 and 29.173 on static 
longitudinal stability would be cost relieving to the manufactures 
because they delete hover demonstrations not relevant to safety and are 
redundant with other requirements. We estimate the average compliance 
costs for such a small firm to be $84,500 as follows:

                            Compliance Costs
------------------------------------------------------------------------
                         Section                               Cost
------------------------------------------------------------------------
27.49...................................................        $21,125
27.143..................................................         26,000
27.173..................................................        (13,000)
27.175..................................................          3,250
27.177..................................................         17,875
27.903..................................................         16,250
                                                         ---------------
    Total...............................................         84,500
------------------------------------------------------------------------

    The annualized cost for this small operator is estimated at $12,030 
($84,500 X 0.142378).\3\
---------------------------------------------------------------------------

    \3\ Uniform Annual Value discounted at 7% over 10-year period.
---------------------------------------------------------------------------

    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. None of the small business operators potentially 
affected by this proposed rule would incurred costs greater that 0.2 
percent of their annual revenue (see table below).

----------------------------------------------------------------------------------------------------------------
                                                                                      Annual
                  U.S. rotorcraft manufactures                      Employment        revenue       Percentage
----------------------------------------------------------------------------------------------------------------
Hiller Aircraft Corp............................................              35      $7,500,000            0.16
Brantly Helicopter Industry.....................................              35      15,000,000            0.08
Enstrom Helicopter Corporation..................................             100      35,000,000            0.03
Schweizer Aircraft Corporation..................................             400      35,000,000            0.03
Erickson Air-Crane..............................................             500      35,000,000            0.03
Robinson Helicopter Company, Inc................................             700      80,000,000            0.02
----------------------------------------------------------------------------------------------------------------

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

International Trade Impact Assessment

    The Trade Agreements Act of 1979 (Pub. L. 96-39) prohibits Federal 
agencies from establishing any 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 
they be the basis for U.S. standards. This proposed rule reflects an 
international effort to have common certification standards, and thus 
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 with the base year 1995) in any one 
year by State, local, and tribal governments, in the aggregate, or by 
the private sector; such a mandate is deemed to be a ``significant 
regulatory action.'' The FAA currently uses an inflation-adjusted value 
of $120.7 million in lieu of $100 million. This proposed rule does not 
contain such a mandate. The requirements of Title II do not apply.

Executive Order 13132, Federalism

    The FAA has analyzed this proposed rule under the principles and 
criteria of Executive Order 13132, Federalism. We determined that this 
action would not

[[Page 42229]]

have a substantial direct effect on the States, on the relationship 
between the national Government and the States, or on the distribution 
of power and responsibilities among the various levels of government, 
and therefore would not have federalism implications.

Regulations Affecting Intrastate Aviation in Alaska

    Section 1205 of the FAA Reauthorization Act of 1996 (codified at 49 
U.S.C. 40113(f)) requires the Administrator, when modifying regulations 
in title 14 of the CFR 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 such 
regulatory distinctions as he or she considers appropriate. Because 
this proposed rule would apply to the certification of future designs 
of normal and transport category rotorcraft and their subsequent 
operation, it could, if adopted, affect intrastate aviation in Alaska. 
The FAA therefore specifically requests comments on whether there is 
justification for applying the proposed rule differently in intrastate 
operations 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 proposed 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 energy impact of the proposed rule has been assessed in 
accordance with the Energy Policy and Conservation Act (EPCA) Public 
Law 94-163, as amended (42 U.S.C. 6362) and the Department of 
Transportation implementing regulations, specifically 14 CFR 313.4, 
that defines a ``major regulatory action.'' We have determined that 
this notice is not a ``major regulatory action'' under the provisions 
of the EPCA. Additionally, we have analyzed this proposal under 
Executive Order 13211, Actions Concerning Regulations that 
Significantly Affect Energy Supply, Distribution, or Use (May 18, 
2001).
    We have determined that this proposed rule 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.

List of Subjects

14 CFR Part 27

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

14 CFR Part 29

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

The Proposed Amendment

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

PART 27--AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT

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

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

    2. 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
* * * * *
    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
    (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; or
    (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.
    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.
    5. 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.
* * * * *
    6. Amend Sec.  27.79 by removing the word ``rotocraft'' and 
replacing it with

[[Page 42230]]

``rotorcraft'' in paragraph (b)(3) and revising paragraphs (a)(1), 
(a)(2) and (b)(2) to read as follows:


Sec.  27.79  Limiting 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
* * * * *
    7. Amend Sec.  27.143 by revising paragraph (a)(2)(v); re-
designating paragraphs (d) and (e) as paragraphs (e) and (f) 
respectively; revising paragraph (c); and adding a new paragraph (d) to 
read as follows:


Sec.  27.143  Controllability and maneuverability.

    (a) * * *
    (2) * * *
    (v) Autorotation;
* * * * *
    (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.
* * * * *
    8. 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.
    9. Amend Sec.  27.175 by removing paragraph (d); revising the 
introductory text in paragraphs (a) and (b); revising paragraphs (b)(3) 
and (b)(5); re-designating paragraph (c) as (d) and 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;
    (i