[Federal Register Volume 75, Number 243 (Monday, December 20, 2010)]
[Proposed Rules]
[Pages 79312-79317]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-31867]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 29
[Docket No. SW022; Special Conditions No. 29-022A-SC]
Special Conditions: Eurocopter France (ECF) Model EC225LP
Helicopter, Installation of a Search and Rescue (SAR) Automatic Flight
Control System (AFCS)
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking.
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[[Page 79313]]
SUMMARY: This document proposes amended special conditions for the ECF
model EC225LP helicopter. This helicopter, as modified by ECF, will
have novel or unusual design features associated with installing an
optional SAR AFCS. Special conditions No. 29-022-SC, published in the
Federal Register on November 6, 2008 (73 FR 65968), addressed these
issues. The proposed amendment revises the original final special
conditions to address comments and to clarify the intent of some
requirements. The applicable airworthiness standards do not contain
adequate or appropriate safety standards for these design features.
These special conditions contain the additional safety standards the
Administrator considers necessary to show a level of safety equivalent
to that established by the existing airworthiness standards.
DATES: We must receive your comments by January 19, 2011.
ADDRESSES: You must mail two copies of your comments to: Federal
Aviation Administration, Rotorcraft Directorate, Attn: Special
Conditions Docket (ASW-111), Docket No. SW022, 2601 Meacham Blvd., Fort
Worth, Texas 76137. You may deliver two copies to the Rotorcraft
Directorate at the above address. You must mark your comments: Docket
No. SW022. You can inspect comments in the Docket on weekdays, except
Federal holidays, between 8:30 a.m. and 4 p.m.
FOR FURTHER INFORMATION CONTACT: FAA, Aircraft Certification Service,
Rotorcraft Directorate, Regulations and Policy Group (ASW-111), Attn:
Stephen Barbini, 2601 Meacham Blvd., Fort Worth, Texas 76137; telephone
(817) 222-5196; facsimile (817) 222-5961.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite interested people to take part in this rulemaking by
sending written comments, data, or views. The most helpful comments
reference a specific portion of the special conditions, explain the
reason for any recommended change, and include supporting data.
We will file in the special conditions docket all comments we
receive, as well as a report summarizing each substantive public
contact with FAA personnel concerning these special conditions. You can
inspect the docket 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 document between 8:30 a.m. and 4 p.m., Monday through
Friday, except Federal holidays.
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
these special conditions based on the comments we receive.
If you want the FAA to acknowledge receipt of your mailed 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 back to you.
Background
On March 27, 2006, ECF applied for a change to Type Certificate
(TC) No. H4EU to install an optional SAR AFCS in the model EC225LP
helicopter. The model EC225LP is a transport category helicopter
certified to Category A requirements when configured for more than nine
passengers and Category A or B requirements when configured for nine or
less passengers. This helicopter is also certified for instrument
flight under the requirements of Appendix B of 14 CFR part 29,
Amendment 29-47.
The use of dedicated AFCS upper modes, in which a fully coupled
autopilot provides operational SAR profiles, is needed for SAR
operations conducted over water in offshore areas clear of
obstructions. The SAR modes enable the helicopter pilot to fly fully
coupled maneuvers, to include predefined search patterns during cruise
flight, and to transition from cruise flight to a stabilized hover and
departure (transition from hover to cruise flight). The SAR AFCS also
includes an auxiliary crew control that allows another crewmember (such
as a hoist operator) to have limited authority to control the
helicopter's longitudinal and lateral position during hover operations.
Flight operations conducted over water at night may have an
extremely limited visual horizon with little visual reference to the
surface even when conducted under Visual Meteorological Conditions
(VMC). Consequently, the certification requirements for SAR modes must
meet Appendix B to 14 CFR part 29. While Appendix B to 14 CFR part 29
prescribes airworthiness criteria for instrument flight, it does not
consider operations below instrument flight minimum speed
(VMINI), whereas the SAR modes allow for coupled operations
at low speed, all-azimuth flight to zero airspeed (hover).
Since SAR operations have traditionally been a public use mission,
the use of SAR modes in civil operations requires special airworthiness
standards (special conditions) to ensure that a level of safety
consistent with Category A and Instrument Flight Rule (IFR)
certification is maintained. In this regard, 14 CFR part 29 lacks
adequate airworthiness standards for AFCS SAR mode certification to
include flight characteristics, performance, and installed equipment
and systems.
Type Certification Basis
Under 14 CFR 21.101, ECF must show the EC225LP, as changed,
continues to meet the applicable provisions of the rules incorporated
by reference in TC No. H4EU or the applicable regulations in effect on
the date of application for the change. The regulations incorporated by
reference in the TC are commonly referred to as the ``original type
certification basis.'' The regulations incorporated by reference in
H4EU are as follows:
a. 14 CFR 21.29.
b. 14 CFR part 29 Amendments 29-1 to 29-25; plus Sec. 29.785
through Amendment 29-28; plus Sec. Sec. 29.963, 29.967, 29.973, 29.975
through Amendment 29-34; plus Sec. Sec. 29.25, 29.865 through
Amendment 29-42; plus Sec. Sec. 29.1, 29.2, 29.49, 29.51, 29.53,
29.55, 29.59, 29.60, 29.61, 29.62, 29.64, 29.65, 29.67, 29.73, 29.75,
29.77, 29.79, 29.81, 29.83, 29.85, 29.87, 29.307, 29.337, 29.351,
29.361, 29.391, 29.395, 29.397, 29.401, 29.403, 29.413, 29.427, 29.501,
29.519, 29.547, 29.549, 29.561(c), 29.561(d), 29.563, 29.602, 29.610,
29.613, 29.621, 29.625, 29.629, 29.631, 29.663, 29.674, 29.727, 29.755,
29.775, 29.783, 29.787, 29.803, 29.805, 29.807, 29.809, 29.811, 29.855,
29.861, 29.901, 29.903, 29.908, 29.917, 29.923, 29.927, 29.954, 29.961,
29.965, 29.969, 29.971, 29.991, 29.997, 29.999, 29.1001, 29.1011,
29.1019, 29.1027, 29.1041, 29.1043, 29.1045, 29.1047, 29.1093, 29.1125,
29.1141, 29.1143, 29.1163, 29.1181, 29.1189, 29.1193, 29.1305, 29.1309,
29.1323, 29.1329, 29.1337, 29.1351, 29.1359, 29.1415, 29.1521, 29.1549,
29.1557, 29.1587, A29, B29, C29, D29 through Amendment 29-47; plus
29.1317 through Amendment 29-49.
c. 14 CFR part 36 Amendment 21 (ICAO Annex 16, Volume 1, Chapter
8).
d. Equivalent Safety Findings:
(1) TC2899RD-R-F-01; Sec. 29.1303(j), Vne aural
warning.
(2) TC2899RD-R-F-02; Sec. 29.1545(b)(4), Airspeed indicators
markings.
(3) TC2899RD-R-F-03; Sec. 29.1549(b), Powerplant instruments
markings.
(4) TC2899RD-R-F-05; Sec. Sec. 29.173, 29,175, Static Longitudinal
Stability.
(5) TC2899RD-R-F-06; 14 CFR part 29, Appendix B, paragraph IV; IFR
[[Page 79314]]
Static Longitudinal Stability-Airspeed stability.
(6) TC2899RD-R-A-01; Sec. 29.807(d)(2), Ditching emergency exits
for passengers.
(7) TC2899RD-R-P-01; Sec. 29.923(a)(2), Rotor drive system and
control mechanism tests.
In addition to the applicable airworthiness standards and special
conditions, the ECF model EC225LP must comply with the noise
certification requirements of 14 CFR part 36.
Regulatory Basis for Special Conditions
If the Administrator finds the applicable airworthiness standards
(that is, 14 CFR part 29) do not contain adequate or appropriate safety
standards for the ECF model EC225LP helicopter because of a novel or
unusual design feature, special conditions are prescribed under Sec.
21.16.
The FAA issues special conditions, as defined in Sec. 11.19, under
Sec. 11.38, and they become part of the type certification basis under
Sec. 21.101.
Special conditions are initially applicable to the model for which
they are issued. Should the TC for that model be amended later to
include any other model that incorporates the same novel or unusual
design feature, or should any other model already included on the same
TC be modified to incorporate the same novel or unusual design feature,
these special conditions would also apply to the other model.
Novel or Unusual Design Features
The ECF model EC225LP helicopter will incorporate the following
novel or unusual design features:
The SAR system is composed of a navigation computer with SAR modes,
an AFCS that provides coupled SAR functions, hoist operator control, a
hover speed reference system, and two radio altimeters. The AFCS
coupled SAR functions include:
(a) Hover hold at selected height above the surface.
(b) Ground speed hold.
(c) Transition down and hover to a waypoint under guidance from the
navigation computer.
(d) SAR pattern, transition down, and hover near a target over
which the helicopter has flown.
(e) Transition up, climb, and capture a cruise height.
(f) Capture and track SAR search patterns generated by the
navigation computer.
(g) Monitor the preselected hover height with automatic increase in
collective if the aircraft height drops below the safe minimum height.
These SAR modes are intended to be used over large bodies of water
in areas clear of obstructions. Further, use of the modes that
transition down from cruise to hover will include operation at
airspeeds below VMINI.
The SAR system only entails navigation, flight control, and coupled
AFCS operation of the helicopter. The system does not include the extra
equipment that may be required for over water flight or external loads
to meet other operational requirements.
Discussion of Comments
Final special conditions; request for comments, No. 29-022-SC for
ECF model EC225LP helicopters was published in the Federal Register on
November 6, 2008 (73 FR 65968), with the comment period closing
December 22, 2008. One commenter, AgustaWestland (AW), responded to our
request for comments and submitted various comments and
recommendations.
Referring to subparagraph (a)(3), which deals with a Go Around
mode, AW states that they do not agree with a requirement for a
function that possibly performs an automatic ascent in case of a
detected failure. They state that this could be even an unsafe maneuver
during hover while operating the winch. They point out that EASA states
in CRI B-03 ``The automatic collective control should provide a high
integrity function that flies up whenever a SAR mode is coupled and the
aircraft is below the minimum safety height, if needed to satisfy the
failure demonstrations in Sec. G, 2. The minimum safety height must
not rely on crew setting only.'' They state there are more generic
requirements that address the safety aspects induced by SAR operation
at low height.
We disagree with the commenter's interpretation of the requirement.
The intent of the requirement is for the go-around mode to be manually
activated by the pilot in order to avoid a hazardous situation. This
action would interrupt any coupled SAR mode and automatically command
the helicopter to ascend and accelerate to the instrument flight rules
(IFR) envelope. The intent is that the go-around mode be provided in
any low-speed environment, such as during hover operations or while
transitioning to a hover. The requirement of subparagraph (a)(3)
differs from the requirement of automatic transition of the helicopter
to the instrument flight envelope in subparagraph (a)(2). Subparagraph
(a)(2) requires an automatic transition to the IFR flight envelope when
a departure from hover mode is activated as part of the normal SAR mode
sequencing. Subparagraph (a)(3) requires a means for the pilot to
interrupt the normal SAR modes sequencing, commanding the AFCS to
automatically transition the helicopter to the IFR flight envelope.
Subparagraph (a)(3) is not intended to require automatic initiation of
a go-around following a single failure of the AFCS. Failure modes are
addressed in subparagraph (a)(9). While we disagree with AW's
interpretation of the requirement, we recognize the wording may be
unclear. We have therefore made a change to subparagraph (a)(3) to
reflect that the required go-around mode is pilot-selectable and the
purpose is to interrupt any other coupled mode. We have also clarified
in subparagraph (a)(2) that this requirement pertains to normal SAR
mode sequencing.
With respect to subparagraphs (b)(3) and (b)(4) of the SAR Mode
System Architecture, the commenter asks if both the sensor variables
and the AFCS mode references should be presented to the crew.
We concur with these recommendations, which is consistent with the
requirement of subparagraph (b)(2). Therefore, subparagraphs (b)(3) and
(b)(4) are revised to additionally require the actual groundspeed and
actual heading to be displayed to the pilot.
For subparagraph (b)(5) of the special conditions, AW asks why the
wind indication should be available only when the automatic modes are
engaged, or transitioning from one mode to another. They state that the
wind information should be made available, independently from any AFCS
engaged mode, at the beginning of the transition from cruise to hover.
We disagree. Subparagraph (b)(5) requires wind speed and wind
direction only when SAR automatic piloting modes are engaged or
transitioning from one SAR mode to another. This requirement is
intended to be a minimum requirement to ensure wind speed and direction
is available for operations near the surface when coupled to the SAR
modes. Thus, the requirement is unchanged.
In reference to subparagraph (c)(3), the commenter states that AC
29-1329.d.(5) explains how the deviations caused by a malfunction
should be evaluated during an instrument landing system (ILS) approach.
The commenter believes that malfunction testing for SAR modes should be
evaluated in the same manner since the SAR-mandatory 15-foot buffer
above the surface is equivalent to the buffer provided in ILS
approaches. Likewise, penetration of this 15-foot buffer does not
guarantee a catastrophic event, but should be treated as a hazardous
event as long as impact
[[Page 79315]]
with the surface is avoided. Therefore, the commenter requests
subparagraph (c)(3) be modified to require failures not shown to be
extremely remote (a safety objective for hazardous failures) must not
result in a loss of height that is greater than half of the MUH with a
minimum of 15 feet above the surface.
We disagree with the commenter. The intent of the requirement to
have a 15-foot minimum height above the surface, following an AFCS
failure, was to provide an acceptable safety margin. The requirement
for such a margin stems from the likelihood of encountering hazards
such as inconsistent wave heights, floating debris, and other
unforeseen obstacles that would create a catastrophic condition if the
helicopter penetrated the 15-foot buffer. Therefore, we consider SAR
AFCS failure conditions that result in recovery closer than 15 feet
above the surface to be catastrophic. We have made non-substantive
changes to improve the intent of the requirement.
Additional wording was added to subparagraph (f)(1)(i)(C) that
provides linkage to the MUH determination made in subparagraph (c)(3).
This change was made for clarification purposes only and is not
intended to increase or alleviate the current requirements. We have
also defined MUH in subparagraph (c)(3). We do not intend for the SAR
AFCS to decouple automatically if the helicopter descends below MUH.
The commenter states that in subparagraphs (g)(4) and (g)(5), the
in-flight demonstration of failures should be required only for
failures that cannot be shown to be extremely remote. AW states that
this requirement would provide some alleviation for the malfunction
flight validation. They state that this should be allowed because SAR
missions are normally conducted by trained pilots and they should be
able to complete the mission even after some malfunction has occurred
in flight. Because of the considerable crew workload involved in a SAR
mission, the commenter believes that it is important to permit coupling
of the Flight Director modes even after a malfunction affecting the
AFCS. The commenter believes that the reduction in pilot workload
provided by a coupled Flight Director ``would considerably reduce the
risk of inadvertent pilot operation, a benefit that should be
considered in comparison to the probability of ``an extremely remote''
failure.''
We do not agree with commenter. The existing requirement does not
require flight testing for failure modes not shown to be extremely
improbable; rather, subparagraphs (g)(4) and (g)(5) permit ground or
flight testing to demonstrate compliance for failure modes not shown to
be extremely improbable. This is consistent with the methodology
prescribed in the advisory circular guidance for AFCS failure modes
testing.
We made some other minor changes to improve and clarify wording,
with no substantive increase or decrease to the current requirements.
In subparagraph (a)(1) we added ``(within the maximum demonstrated
wind envelope)'' to highlight that safe and controlled flight is
required throughout the wind envelope. Adding this phrase does not
change our intent of SAR envelope definition.
We added, ``Pilot-commanded descent below the safe minimum height
is acceptable provided the alerting requirements in (b)(7)(i) are
sufficient to alert the pilot of this encroachment'' to subparagraph
(a)(4). This clarifies that the SAR AFCS is permitted to descend below
the stored or pilot-selected safe minimum height only when commanded by
the pilot, provided the alerting requirements are sufficient to alert
the pilot of the descent.
We modified subparagraph (b)(6) to indicate that the AFCS system
must monitor for all deviations and failures, not just those that
create a hazard, which was our original intent. The alerting
requirement does not change; a pilot alert is still required for all
deviations and all failures that require pilot-corrective action.
Clarifications were made to subparagraph (b)(7) by adding
subparagraph (iii) for normal transitions. We have also denoted the
remainder of the subparagraph as a note. This makes the requirement
more specific.
We clarified in subparagraph (b)(8) that the hoist operator control
has limited authority.
Subparagraph (b)(8)(iii) of the current special condition contains
two requirements. We have separated them, so subparagraph (b)(8)(iii)
only contains the hoist operator control noninterference requirement
and subparagraph (b)(8)(iv) contains the pilot override criteria for
the hoist control.
We modified subparagraph (d)(2) by deleting ``danger of '' from the
first sentence. This change does not alter the intent of this
requirement.
Subparagraph (d)(3)(iii)(B) was modified to incorporate more
general terms to clarify the requirement.
We have changed subparagraph (b)(10) to state a functional hazard
assessment must address all failure conditions, not just those that
represent catastrophic failure conditions. This change makes this SAR
special condition requirement consistent with the requirements of Sec.
29.1309.
We have changed the second paragraph in subparagraph (e)(1)(ii) to
a note. This ``note'' provides information only and is better
characterized as a ``note.'' The original wording was always intended
to stand as a note, but it was not previously marked as one.
We removed the parenthetical from subparagraph (g)(4) as it is not
needed. The intent of this requirement has not changed.
Finally, we clarified subparagraphs (g)(4)(i) and (g)(4)(ii), by
changing ``transition,'' ``hover,'' and ``cruise'' to ``transition
modes,'' ``hover modes,'' and ``cruise modes,'' respectively. This
general wording allows an applicant more flexibility in the use of SAR
mode terminology.
Applicability
These special conditions apply to the ECF model EC225LP
helicopters. Should ECF apply at a later date for a change to the TC to
include another model incorporating the same novel or unusual design
feature, these special conditions would apply to that model as well
under the provisions of Sec. 21.101(d).
Conclusion
This action affects only certain novel or unusual design features
on one model of helicopter. It is not a rule of general applicability.
List of Subjects in 14 CFR Part 29
Aircraft, Aviation safety.
The authority citation for these special conditions is as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701-44702, 44704.
The Special Conditions
Accordingly, the Federal Aviation Administration (FAA) proposes
replacing Special Conditions No. 29-022-SC, Docket No. SW022 (73 FR
65968, November 6, 2008) with the following special conditions as part
of the type certification basis for Eurocopter France model EC225LP
helicopters when the optional Search and Rescue (SAR) Automatic Flight
Control System (AFCS) is installed:
In addition to the part 29 certification requirements for Category
A and helicopter instrument flight (Appendix B), the following
additional requirements must be met for certification of the SAR AFCS:
(a) SAR Flight Modes. The coupled SAR flight modes must provide:
[[Page 79316]]
(1) Safe and controlled flight in three axes (lateral and
longitudinal position/speed and height/vertical speed) at all airspeeds
from instrument flight minimum speed (VMINI) to a hover
(within the maximum demonstrated wind envelope).
(2) Automatic transition to the helicopter instrument flight
(Appendix B) envelope as part of the normal SAR mode sequencing.
(3) A pilot-selectable Go-Around mode that safely interrupts any
other coupled mode and automatically transitions to the helicopter
instrument flight (Appendix B) envelope.
(4) A means to prevent unintended flight below a safe minimum
height. Pilot-commanded descent below the safe minimum height is
acceptable provided the alerting requirements in (b)(7)(i) are
sufficient to alert the pilot of this descent below safe minimum
height.
(b) SAR Mode System Architecture. To support the integrity of the
SAR modes, the following system architecture is required:
(1) A system for limiting the engine power demanded by the AFCS
when any of the automatic piloting modes are engaged, so FADEC power
limitations, such as torque and temperature, are not exceeded.
(2) A system providing the aircraft height above the surface and
final pilot-selected height at a location on the instrument panel in a
position acceptable to the FAA that will make it plainly visible to and
usable by any pilot at their station.
(3) A system providing the aircraft heading and the pilot-selected
heading at a location on the instrument panel in a position acceptable
to the FAA that will make it plainly visible to and usable by any pilot
at their station.
(4) A system providing the aircraft longitudinal and lateral ground
speeds and the pilot-selected longitudinal and lateral ground speeds
when used by the AFCS in the flight envelope where airspeed indications
become unreliable. This information must be presented at a location on
the instrument panel in a position acceptable to the FAA that is
plainly visible to and usable by any pilot at their station.
(5) A system providing wind speed and wind direction when automatic
piloting modes are engaged or transitioning from one mode to another.
(6) A system that monitors for flight guidance deviations and
failures with an appropriate alerting function that enables the flight
crew to take appropriate corrective action.
(7) An alerting system must provide visual or aural alerts, or
both, to the flight crew under any of the following conditions:
(i) When the stored or pilot-selected safe minimum height is
reached.
(ii) When a SAR mode system malfunction occurs.
(iii) When the AFCS changes modes automatically from one SAR mode
to another.
Note: For normal transitions from one SAR mode to another, a
single visual or aural alert may suffice. For a SAR mode malfunction
or a mode having a time-critical component, the flight crew alerting
system must activate early enough to allow the flight crew to take
timely and appropriate action. The alerting system means must be
designed to alert the flight crew in order to minimize crew errors
that could create an additional hazard.
(8) The SAR system hoist operator control is considered a flight
control with limited authority and must comply with the following:
(i) The hoist operator control must be designed and located to
provide for convenient operation and to prevent confusion and
inadvertent operation.
(ii) The helicopter must be safely controllable by the hoist
operator control throughout the range of that control.
(iii) The hoist operator control may not interfere with the safe
operation of the helicopter.
(iv) Pilot and copilot flight controls must be able to smoothly
override the control authority of the hoist operator control, without
exceptional piloting skill, alertness, or strength, and without the
danger of exceeding any other limitation because of the override.
(9) The reliability of the AFCS must be related to the effects of
its failure. The occurrence of any failure condition that would prevent
continued safe flight and landing must be extremely improbable. For any
failure condition of the AFCS which is not shown to be extremely
improbable:
(i) The helicopter must be safely controllable and capable of
continued safe flight without exceptional piloting skill, alertness, or
strength. Additional unrelated probable failures affecting the control
system must be evaluated.
(ii) The AFCS must be designed so that it cannot create a hazardous
deviation in the flight path or produce hazardous loads on the
helicopter during normal operation or in the event of a malfunction or
failure, assuming corrective action begins within an appropriate period
of time. Where multiple systems are installed, subsequent malfunction
conditions must be evaluated in sequence unless their occurrence is
shown to be improbable.
(10) A functional hazard assessment (FHA) and a system safety
assessment must be provided to address the failure conditions
associated with SAR operations. For SAR catastrophic failure
conditions, changes may be required to the following:
(i) System architecture.
(ii) Software and complex electronic hardware design assurance
levels.
(iii) HIRF test levels.
(iv) Instructions for continued airworthiness.
The assessments must consider all the systems required for SAR
operations to include the AFCS, all associated AFCS sensors (for
example, radio altimeter), and primary flight displays. Electrical and
electronic systems with SAR catastrophic failure conditions (for
example, AFCS) must comply with the Sec. 29.1317(a)(4) High Intensity
Radiated Field (HIRF) requirements.
(c) SAR Mode Performance Requirements.
(1) The SAR modes must be demonstrated in the requested flight
envelope for the following minimum sea-state and wind conditions:
(i) Sea-State: Wave height of 2.5 meters (8.2 feet), considering
both short and long swells.
(ii) Wind: 25 knots headwind; 17 knots for all other azimuths.
(2) The selected hover height and hover velocity must be captured
(to include the transition from one captured mode to another captured
mode) accurately and smoothly and not exhibit any significant overshoot
or oscillation.
(3) For any single failure or any combination of failures of the
AFCS that is not shown to be extremely improbable, the recovery must
not result in a loss of height greater than half of the minimum use
height (MUH) with a minimum margin of 15 feet above the surface. MUH is
the minimum height at which any SAR AFCS mode can be engaged.
(4) The SAR mode system must be usable up to the maximum certified
gross weight of the aircraft or to the lower of the following weights:
(i) Maximum emergency flotation weight.
(ii) Maximum hover Out-of-Ground Effect (OGE) weight.
(iii) Maximum demonstrated weight.
(d) Flight Characteristics.
(1) The basic aircraft must meet all the part 29 airworthiness
criteria for helicopter instrument flight (Appendix B).
(2) For SAR mode coupled flight below VMINI, at the
maximum demonstrated winds, the helicopter must be able to maintain any
required flight condition and make a smooth transition from any flight
condition to any other flight condition without
[[Page 79317]]
requiring exceptional piloting skill, alertness, or strength, and
without exceeding the limit load factor. This requirement also includes
aircraft control through the hoist operator's control.
(3) For SAR modes at airspeeds below VMINI, the
following requirements of Appendix B to part 29 must be met and will be
used as an extension to the IFR certification envelope of the basic
aircraft:
(i) Static Longitudinal Stability: The requirements of paragraph IV
of Appendix B are not applicable.
(ii) Static Lateral-Directional Stability: The requirements of
paragraph V of Appendix B are not applicable.
(iii) Dynamic Stability: The requirements of paragraph VI of
Appendix B are replaced with the following two paragraphs:
(A) Any oscillation must be damped and any aperiodic response must
not double in amplitude in less than 10 seconds. This requirement must
also be met with degraded upper mode(s) of the AFCS. An ``upper mode''
is a mode that utilizes a fully coupled autopilot to provide an
operational SAR profile.
(B) After any upset, the AFCS must return the aircraft to the last
commanded position within 10 seconds or less.
(4) With any of the upper mode(s) of the AFCS engaged, the pilot
must be able to manually recover the aircraft and transition to the
normal (Appendix B) IFR flight profile envelope without exceptional
skill, alertness, or strength.
(e) One-Engine Inoperative (OEI) Performance Information.
(1) The following performance information must be provided in the
Rotorcraft Flight Manual Supplement (RFMS):
(i) OEI performance information and emergency procedures, providing
the maximum weight that will provide a minimum clearance of 15 feet
above the surface, following failure of the critical engine in a hover.
The maximum weight must be presented as a function of the hover height
for the temperature and pressure altitude range requested for
certification. The effects of wind must be reflected in the hover
performance information.
(ii) Hover OGE performance with the critical engine inoperative for
OEI continuous and time-limited power ratings for those weights,
altitudes, and temperatures for which certification is requested.
Note: These OEI performance requirements do not replace
performance requirements that may be needed to comply with the
airworthiness or operational standards (Sec. 29.865 or 14 CFR part
133) for external loads or human external cargo.
(f) RFMS.
(1) The RFMS must contain, at a minimum:
(i) Limitations necessary for safe operation of the SAR system to
include:
(A) Minimum crew requirements.
(B) Maximum SAR weight.
(C) Engagement criteria for each of the SAR modes to include MUH
(as determined in subparagraph (c)(3)).
(ii) Normal and emergency procedures for operation of the SAR
system (to include operation of the hoist operator control), with AFCS
failure modes, AFCS degraded modes, and engine failures.
(iii) Performance information:
(A) OEI performance and height-loss.
(B) Hover OGE performance information, utilizing OEI continuous and
time-limited power ratings.
(C) The maximum wind envelope demonstrated in flight test.
(g) Flight Demonstration.
(1) Before approval of the SAR system, an acceptable flight
demonstration of all the coupled SAR modes is required.
(2) The AFCS must provide fail-safe operations during coupled
maneuvers. The demonstration of fail-safe operations must include a
pilot workload assessment associated with manually flying the aircraft
to an altitude greater than 200 feet above the surface and an airspeed
of at least the best rate of climb airspeed (Vy).
(3) For any failure condition of the SAR system not shown to be
extremely improbable, the pilot must be able to make a smooth
transition from one flight mode to another without exceptional piloting
skill, alertness, or strength.
(4) Failure conditions that are not shown to be extremely
improbable must be demonstrated by analysis, ground testing, or flight
testing. For failures demonstrated in flight, the following normal
pilot recovery times are acceptable:
(i) Transition modes (Cruise-to-Hover/Hover-to-Cruise) and Hover
modes: Normal pilot recognition plus 1 second.
(ii) Cruise modes: Normal pilot recognition plus 3 seconds.
(5) All AFCS malfunctions must include evaluation at the low-speed
and high-power flight conditions typical of SAR operations.
Additionally, AFCS hard-over, slow-over, and oscillatory malfunctions,
particularly in yaw, require evaluation. AFCS malfunction testing must
include a single or a combination of failures (for example, erroneous
data from and loss of the radio altimeter, attitude, heading, and
altitude sensors) which are not shown to be extremely improbable.
(6) The flight demonstration must include the following
environmental conditions:
(i) Swell into wind.
(ii) Swell and wind from different directions.
(iii) Cross swell.
(iv) Swell of different lengths (short and long swell).
Issued in Fort Worth, Texas, on December 14, 2010.
Bruce E. Cain,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2010-31867 Filed 12-17-10; 8:45 am]
BILLING CODE 4910-13-P