Special Conditions: Agusta S.p.A. Model AW139 and AB139 Helicopter, Installation of a Search and Rescue (SAR) Automatic Flight Control System (AFCS), 44110-44113 [2012-18199]

Agencies

• Federal Aviation Administration
• DEPARTMENT OF TRANSPORTATION

[Federal Register Volume 77, Number 145 (Friday, July 27, 2012)]
[Rules and Regulations]
[Pages 44110-44113]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-18199]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 29

[Docket No. FAA-2012-0785; Special Conditions No. 29-027-SC]


Special Conditions: Agusta S.p.A. Model AW139 and AB139 
Helicopter, Installation of a Search and Rescue (SAR) Automatic Flight 
Control System (AFCS)

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final special conditions; request for comments.

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SUMMARY: These special conditions are issued for the Agusta S.p.A. 
(Agusta) Model AW139 and AB139 helicopters. These model helicopters, as 
modified by Agusta, will have novel or unusual design features 
associated with installing an optional SAR AFCS. The applicable 
airworthiness standards do not contain adequate or appropriate safety 
standards for this design feature. 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: The effective date of these special conditions is July 18, 2012. 
We must receive your comments by September 25, 2012.

ADDRESSES: Send comments identified by docket number [FAA-2012-0785] 
using any of the following methods:
     Federal eRegulations Portal: Go to https://www.regulations.gov and follow the online instructions for sending your 
comments electronically.
     Mail: Send comments to Docket Operations, M-30, U.S. 
Department of Transportation (DOT), 1200 New Jersey Avenue SE., Room 
W12-140, West Building Ground Floor, Washington, DC 20590-0001.
     Hand Delivery of Courier: Deliver comments to the ``Mail'' 
address between 9 a.m., and 5 p.m., Monday through Friday, except 
Federal holidays.
     Fax: Fax comments to Docket Operations at 202-493-2251.
    Privacy: The FAA will post all comments it receives, without 
change, to https://regulations.gov, including any personal information 
the commenter provides. Using the search function of the docket Web 
site, anyone can find and read the electronic form of all comments 
received into any FAA docket, including the name of the individual 
sending the comment (or signing the comment for an association, 
business, labor union, etc.). DOT's complete Privacy Act Statement can 
be found in the Federal Register published on April 11, 2000 (65 FR 
19477-19478), as well as at https://DocketsInfo.dot.gov.
    Docket: You can read the background documents or comments received 
at https://www.regulations.gov. Follow the online instructions for 
accessing the docket or go to the Docket Operations in Room @12-140 of 
the West Building Ground Floor at 1200 New Jersey Avenue SE., 
Washington, DC, between 9 a.m., and 5 p.m., Monday through Friday, 
except Federal holidays.

FOR FURTHER INFORMATION CONTACT: 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: 

Reason for No Prior Notice and Comment Before Adoption

    The substance of these special conditions has been subjected to the 
notice and comment period previously and has been derived without 
substantive change from those previously issued. It is unlikely that 
prior public comment would result in a significant change from the 
substance contained herein. Further, a delay in the effective date of 
these special conditions would significantly delay issuance of the 
design approval and thus delivery of the helicopter, which is imminent. 
Therefore, the FAA has determined that prior public notice and comment 
are unnecessary, impracticable, and contrary to the public interest, 
and finds good cause exists for adopting these special conditions upon 
issuance. The FAA is requesting comments to allow interested persons to 
submit views that may not have been submitted in response to the prior 
opportunities for comment.

Comments Invited

    While we did not precede this with a notice of proposed special 
conditions, we invite interested people to take part in this action 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 consider all comments we receive by the closing date for 
comments. We will consider comments filed late if it is possible to do 
so without incurring additional expense or delay. We may change these 
special conditions based on the comments we receive.

Background and Discussion

    On November 11, 2008, Agusta applied for a change to Type 
Certificate (TC) No. R00002RD to install an optional SAR AFCS in the 
Model AB139 and AW139 helicopters. The AB139 and AW139 models are 
transport category helicopters certificated to Category A and Category 
B requirements, and instrument flight certificated under the 
requirements of Appendix B to 14 CFR part 29, Amendment 29-40.
    There is a need to use dedicated AFCS upper modes, in which a fully 
coupled autopilot provides operational SAR profiles, 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. 
Consequently, the certification requirements for SAR modes must meet 
Appendix B to 14 CFR part 29 for helicopter instrument flight. While 
this appendix 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 maintain a level of safety

[[Page 44111]]

consistent with Category A and Instrument Flight Rule (IFR) 
certification. 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, Agusta must show the AW139 and AB139 model 
helicopters, as changed, continue to meet either the applicable 
provisions of the rules incorporated by reference in TC No. R00002RD or 
the applicable regulations in effect on the date of application for the 
change, depending on the significance of the change as defined by 14 
CFR 21.101. The regulations incorporated by reference in the TC are 
commonly referred to as the ``original type certification basis.'' The 
regulations incorporated by reference in R00002RD are as follows:
    (a) 14 CFR 21.29 and Part 29, Amendments 29-1 through 29-45.
    (b) Appendix B to Part 29, Amendment 29-40.
    (c) 14 CFR part 36, Appendix H, Amendment 36-1 through Amendment 
36-25.
    (d) Special Condition No. 29-0010-SC, High Intensity Radiated 
Fields (HIRF), dated Feb. 19, 2004.
    (e) Equivalent Level of Safety Findings issued against:
    (1) 14 CFR 29.1305, as documented in AB139 FAA Memo dated Dec. 20, 
2004.
    (2) 14 CFR 29.1321, as documented in AB139 FAA Memo dated Dec. 20, 
2004.

Regulatory Basis for Special Conditions

    If the Administrator finds the applicable airworthiness standards 
(i.e., 14 CFR part 29) do not contain adequate or appropriate safety 
standards for the Agusta model AW139 and AB139 helicopters because of a 
novel or unusual design feature, special conditions are prescribed 
under 14 CFR 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 Agusta model AW139 and AB139 helicopters 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 
additional equipment that may be required for over water flight or 
external loads to meet other operational requirements.

Applicability

    These special conditions apply to the Agusta Model AW139 and AB139 
helicopters. Should Agusta 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 two model helicopters (i.e., AW139 and AB139 helicopters). It is not 
a rule of general applicability.

List of Subjects in 14 CFR Part 29

    Aircraft, Aviation safety.

0
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, pursuant to the authority delegated to me by the 
Administrator, the following special conditions are issued as part of 
the type certification basis for Agusta Model AW139 and AB139 
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:
    (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 the helicopter to the 
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) 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 full authority 
digital engine control 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

[[Page 44112]]

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, and contains an alerting function that provides the flight 
crew with enough information to take appropriate corrective action.
    (7) The alerting system must provide visual or aural alerts, or 
both, to the flight crew under any of the below 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.

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 limited 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 and a system safety assessment 
must be provided to the FAA that addresses the failure conditions 
associated with SAR operations.
    (i) For SAR catastrophic failure conditions, changes may be 
required to the following:
    (A) System architecture.
    (B) Software and complex electronic hardware design assurance 
levels.
    (C) High Intensity Radiated Field (HIRF) test levels.
    (D) Instructions for continued airworthiness.
    (ii) 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) HIRF 
requirements.
    (c) SAR Mode Performance Requirements.
    (1) Demonstrate the SAR modes for the requested flight envelope, 
including 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) The minimum use height (MUH) for the SAR modes must be no more 
than the maximum loss of height following any single failure or any 
combination of failures not shown to be extremely improbable, plus an 
additional 15 feet. The MUH is the minimum height at which any SAR AFCS 
mode may 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 of 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 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

[[Page 44113]]

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 (14 CFR 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 paragraph (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 (e.g., erroneous data 
from and loss of the radio altimeter, attitude, heading, and altitude 
sensors) that 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 July 18, 2012.
Kimberly K. Smith,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2012-18199 Filed 7-26-12; 8:45 am]
BILLING CODE 4910-13-P