Special Conditions: Robinson Helicopter Company R66 Helicopters, 14 CFR 27.1309, Installation of an Autopilot (AP) Stabilization Augmentation System (SAS), 28449-28451 [E9-14103]

Download as PDF 28449 Proposed Rules Federal Register Vol. 74, No. 114 Tuesday, June 16, 2009 This section of the FEDERAL REGISTER contains notices to the public of the proposed issuance of rules and regulations. The purpose of these notices is to give interested persons an opportunity to participate in the rule making prior to the adoption of the final rules. Engineer, FAA, Rotorcraft Directorate (ASW–112), Aircraft Certification Service, 2601 Meacham Blvd., Fort Worth, Texas, 76137; telephone (817) 222–5114; facsimile (817) 222–5961. SUPPLEMENTARY INFORMATION: Comments Invited DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 21 and 27 [Docket No. SW021; Notice No. 27–021–SC] Special Conditions: Robinson Helicopter Company R66 Helicopters, 14 CFR 27.1309, Installation of an Autopilot (AP) Stabilization Augmentation System (SAS) cprice-sewell on PRODPC61 with PROPOSALS AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed special conditions. SUMMARY: This action proposes special conditions for installing an Autopilot Stabilization Augmentation System (AP/ SAS) in the Robinson Helicopter Company (Robinson) Model R66 helicopter. This helicopter will have novel or unusual design features associated with installing a complex AP/SAS that has potential failure modes with more severe adverse results than those envisioned by the existing applicable airworthiness standards. The applicable airworthiness standards do not contain adequate or appropriate safety standards for this design feature. This proposed special condition contains the added safety standards the Administrator considers necessary to establish a level of safety equivalent to the existing airworthiness standards. DATES: We must receive your comments by July 31, 2009. ADDRESSES: Mail two copies of your comments to: Federal Aviation Administration, Rotorcraft Directorate, Attn: Rules Docket (ASW–111), Docket No. SW021, 2601 Meacham Blvd., Fort Worth, Texas 76137. You may deliver two copies to the Rotorcraft Directorate at this address. You must mark your comments for: Docket No. SW021. You may inspect comments in the Rules Docket weekdays, except Federal holidays, between 8:30 a.m. and 4 p.m. FOR FURTHER INFORMATION CONTACT: George Schwab, Aviation Safety VerDate Nov<24>2008 14:59 Jun 15, 2009 Jkt 217001 We invite you 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 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 on 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 additional 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 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 November 1, 2006, Robinson proposed a change to the certification basis, through the FAA’s Los Angeles Aircraft Certification Office (LA ACO), that would include installing an AP/ SAS as part of the application for type certification for the Robinson Model R66 helicopter. The Robinson Model R66 helicopter is a part 27 Normal category, single turbine engine, conventional helicopter designed for civil operation. The helicopter is capable of carrying four passengers with one pilot, and has a maximum gross weight of approximately 2,650 pounds. The major design features include a 2- PO 00000 Frm 00001 Fmt 4702 Sfmt 4702 blade, fully articulated main rotor, a 2blade anti-torque tail rotor, a skid landing gear, and a visual flight rule (VFR) basic avionics configuration. Robinson proposes offering the Hoh Aeronautics, Inc. two-axis AP/SAS as a factory installed option. Type Certification Basis Under 14 CFR 21.17, Robinson must show that the Model R66 helicopter meets the applicable provisions of 14 CFR part 27, as amended by Amendments 27–1 through 27–40. If the Administrator finds the applicable airworthiness standards, as they apply to the type certification, do not contain adequate or appropriate safety standards because of a novel or unusual design feature, special conditions are prescribed under § 21.16. Special conditions, as appropriate, are defined in § 11.19, and issued by following the procedures in § 11.38 and become part of the type certification basis under § 21.17(a)(2). Special conditions are initially applicable to the model for which they are issued. Should the Type Certificate for that model be amended later to include any other model that incorporates the same novel or unusual design feature, the special condition would also apply to the other model under § 21.101. Novel or Unusual Design Features The Robinson Model R66 helicopter will be required to show compliance with the current applicable requirements without the optional AP/ SAS system. The Hoh Aeronautics, Inc. AP/SAS system will constitute a novel or unusual design feature when installed in the Model R66 helicopter. Although this AP/SAS system performs non-critical control functions, the possible failure modes for this system and their effects on the ability of the helicopter to continue safe flight and landing are more severe than those envisioned when the present safety standards were promulgated. Therefore, additional safety standards are necessary. Discussion Failure Condition Categories The effect on safety is not adequately covered under § 27.1309 for the application of new technology and new application of standard technology. E:\FR\FM\16JNP1.SGM 16JNP1 28450 Federal Register / Vol. 74, No. 114 / Tuesday, June 16, 2009 / Proposed Rules Specifically, the present provisions of § 27.1309(c) do not adequately address the safety requirements for systems whose failures could result in Catastrophic or Hazardous/Severe-Major failure conditions, or for complex systems whose failures could result in Major failure conditions. To comply with the provision of the special condition, we propose to require that Robinson provide the FAA with a Systems Safety Assessment (SSA) for the final Hoh Aeronautics Inc. AP/SAS installation configuration that will adequately address the safety objectives established by the Functional Hazard Assessment (FHA) and the Preliminary System Safety Assessment (PSSA), including the Fault Tree Analysis (FTA). This must ensure that all failure modes and their resulting effects are adequately addressed for the installed AP/SAS. The SSA process, FHA, PSSA, and FTA are all parts of the overall Safety Assessment (SA) process discussed in FAA Advisory Circular (AC) 27–1B (Certification of Normal Category Rotorcraft) and SAE document ARP 4761 (Guidelines and Methods for Conducting the Safety Assessment Process on civil airborne Systems and Equipment). This special condition requires that the AP/SAS system installed on a Robinson Model R66 helicopter meet these requirements to adequately address the failure effects identified by the FHA, and subsequently verified by the SSA, within the defined design integrity requirements. Applicability cprice-sewell on PRODPC61 with PROPOSALS As discussed, this special condition is applicable to the Robinson Model R66 helicopter with the Hoh Aeronautics, Inc. AP/SAS installed as a factory option under the pending application for the Robinson Model R66 type certificate. Should Robinson Helicopter Company apply at a later date for a change to the type certificate to include another model incorporating this same factory installed option Hoh Aeronautics, Inc. AP/SAS novel or unusual design feature, this special condition would also apply to that model, under the provisions of § 21.101(b)(1). Conclusion This action affects only the Robinson R66 model series of helicopter with the novel or unusual design features of a Hoh Aeronautics, Inc. AP/SAS installed. It is not a rule of general applicability. VerDate Nov<24>2008 14:59 Jun 15, 2009 Jkt 217001 List of Subjects in 14 CFR Parts 21 and 27 Aircraft, Aviation safety, Exports, Imports, Reporting and recordkeeping requirements. The authority citation for these special conditions is as follows: Authority: 42 U.S.C. 7572; 49 U.S.C. 106(g), 40105, 40113, 44701–44702, 44704, 44709, 44711, 44713, 44715, 45303. The Proposed Special Conditions Accordingly, the Federal Aviation Administration (FAA) proposes the following special conditions as part of the type certification basis for Robinson Model R66 helicopters: For installation of a Hoh Aeronautics, Inc. Autopilot/Stability Augmentation System on a Robinson Model R66 helicopter, the system must be designed and installed so that the failure conditions identified in the Functional Hazard Assessment and addressed by the System Safety Assessment, after design completion, are adequately addressed in accordance with the Definitions for the Failure Condition Categories and the Requirements (including the design integrity, design environmental, and test and analysis requirements) of this special condition. Definitions Failure Conditions are conditions that result from a failure and are classified, according to the severity of their effects on the rotorcraft, into one of the following categories: (1) No Effect—Failure Conditions that would have no effect on safety; for example, Failure Conditions that would not affect the operational capability of the rotorcraft or increase crew workload; however, could result in an inconvenience to the occupants, excluding the flight crew. (2) Minor—Failure conditions which would not significantly reduce rotorcraft safety, and would involve crew actions that are well within their capabilities. Minor failure conditions would include, for example, a slight reduction in safety margins or functional capabilities, a slight increase in crew workload such as routine flight plan changes, or result in some physical discomfort to occupants. (3) Major—Failure conditions which would reduce the capability of the rotorcraft or the ability of the crew to cope with adverse operating conditions to the extent there would be, for example, a significant reduction in safety margins or functional capabilities; a significant increase in crew workload or result in impairing crew efficiency; physical distress to occupants, including injuries; or physical discomfort to the flight crew. (4) Hazardous/Severe-Major—Failure conditions that would reduce the capability of the rotorcraft or the ability of the crew to cope with adverse operating conditions to the extent there would be: (i) A large reduction in safety margins or functional capabilities; (ii) Physical distress or excessive workload that would impair the flight crew’s ability to the extent that they could not be relied on PO 00000 Frm 00002 Fmt 4702 Sfmt 4702 to perform their tasks accurately or completely; or (iii) Possible serious or fatal injury to a passenger or a cabin crewmember, excluding the flight crew. Note: Hazardous/Severe-Major failure conditions can include events that are manageable by the crew by use of proper procedures, which, if not carried out correctly or in a timely manner, may result in a Catastrophic Event. (5) Catastrophic—Failure Conditions which would result in multiple fatalities to occupants, fatalities or incapacitation to the flight crew, or result in the inability of the rotorcraft to continue safe flight and landing. Requirements Robinson must comply with the existing requirements of § 27.1309 for all applicable design and operational aspects of the AP/ SAS with the failure condition categories of No Effect, Minor, and for non-complex systems whose failure condition category is classified as Major. Robinson must also comply with the requirements of this special condition for all applicable design and operational aspects of the AP/SAS with the failure condition categories of Catastrophic and Hazardous/Severe-Major, and for complex systems classified as a Major failure condition category. A complex system is a system whose operations, failure modes, or failure effects are difficult to understand without the aid of analytical methods (for example, Fault Tree Analysis, Failure Modes and Effect Analysis, Functional Hazard Assessment, etc.). a. Design Integrity Requirements Each of the failure condition categories defined in this special condition relate to the corresponding aircraft system integrity requirements. The design integrity requirements for the Hoh Aeronautics, Inc. AP/SAS as they relate to the allowed probability of occurrence for each failure condition category, and the proposed software design assurance level, are as follows: Major—Condition classified as a ‘‘Major failure condition’’ and resulting in Major effects must be shown to be improbable, or at or less than 1 × 10¥5 failures/hour, and associated software must be developed to the RTCA/DO–178B (Software Considerations in Airborne Systems And Equipment Certification) software design assurance Level C. Hazardous/Severe-Major—Condition classified as a ‘‘Hazardous/Severe-Major failure condition’’ and resulting in Hazardous/Severe-Major effects must be shown to be extremely remote or at or less than 1 × 10¥7 failures/hour, and associated software must be developed to the RTCA/ DO–178B (Software Considerations in Airborne Systems And Equipment Certification) software design assurance Level B. Catastrophic—Condition classified as a ‘‘Catastrophic failure condition’’ and resulting in Catastrophic effects must be shown to be extremely improbable or at or less than 1 × 10¥9 failures/hour, and associated software must be developed to the E:\FR\FM\16JNP1.SGM 16JNP1 Federal Register / Vol. 74, No. 114 / Tuesday, June 16, 2009 / Proposed Rules RTCA/DO–178B (Software Considerations in Airborne Systems And Equipment Certification) Level A software design assurance level. b. Design Environmental Requirements Robinson must qualify the AP/SAS system equipment to the appropriate environmental level in the RTCA document DO–160F (Environmental Conditions and Test Procedures for Airborne Equipment), for all relevant aspects. This must show that the AP/SAS system performs its intended function under any foreseeable operating condition, which includes the expected environment in which the AP/SAS is intended to operate. Some of the main considerations for environmental concerns are installation locations and the resulting exposure to environmental conditions for the AP/SAS system equipment, including considerations for other equipment that may be affected environmentally by the AP/SAS equipment installation. The level of environmental qualification must be related to the severity of the considered failure condition and effects on the aircraft. c. Test & Analysis Requirements cprice-sewell on PRODPC61 with PROPOSALS Compliance with these requirements may be shown by a variety of methods, which typically consist of analysis, flight tests, ground tests, and simulation, as a minimum. Compliance methodology is partly related to the associated failure condition category. If the AP/SAS is a complex system, compliance with the requirements for aspects of the AP/ SAS that can result in failure conditions classified as Major may be shown by analysis, in combination with appropriate testing to validate the analysis. Compliance with the requirements for aspects of the AP/ SAS that can result in failure conditions classified as Hazardous/Severe-Major may be shown by flight-testing in combination with analysis and simulation, and the appropriate testing to validate the analysis. Flight tests may be limited for this classification of failures due to safety considerations. Compliance with the requirements for aspects of the AP/SAS that can result in failure conditions classified as Catastrophic may be shown by analysis and validated by appropriate testing in combination with simulation. Very limited flight tests in combination with simulation may be used as a part of a showing of compliance for failures in this classification. Flight tests are performed only in circumstances that use operational variations or extrapolations from other flight performance aspects to address flight safety. Issued in Fort Worth, Texas, on June 11, 2009. Mark R. Schilling, Acting Manager, Rotorcraft Directorate, Aircraft Certification Service. [FR Doc. E9–14103 Filed 6–15–09; 8:45 am] BILLING CODE 4910–13–P VerDate Nov<24>2008 14:59 Jun 15, 2009 Jkt 217001 ENVIRONMENTAL PROTECTION AGENCY 40 CFR Parts 51, 60, 61 and 63 [EPA–HQ–OAR–2008–0531; FRL–8917–3] RIN 2060–AP23 Restructuring of the Stationary Source Audit Program AGENCY: Environmental Protection Agency (EPA). ACTION: Proposed rule. SUMMARY: The action proposes amendments to the General Provisions to allow accredited providers to supply stationary source audit samples and to require sources to obtain and use these samples from the accredited providers instead of from EPA, as is the current practice. In addition, this proposed rule incorporates by reference Volume 3, ‘‘General Requirements for Environmental Proficiency Test Providers’’ adopted December 22, 2007, as an example of an acceptable accredited proficiency test sample provider (APTSP) technical criteria document. This document outlines the criteria an accredited provider program must meet for the samples to be acceptable. Requirements pertaining to the audit samples have all been moved to the General Provisions and have been removed from the test methods because the current language in the test methods regarding audit samples is inconsistent from method to method. Therefore, deleting all references to audit samples in the test methods eliminates any possible confusion and inconsistencies. Under this proposed amendment, the requirement to use an audit sample during a compliance test will apply to all test methods for which a commercially available audit exists. DATES: Comments must be received on or before July 16, 2009. Under the Paperwork Reduction Act, comments on the information collection provisions are best assured of having full effect if the Office of Management and Budget (OMB) receives a copy of your comments on or before July 16, 2009. ADDRESSES: Submit your comments, identified by Docket ID Number EPA– HQ–OAR–2008–0531, by one of the following methods: • https://www.regulations.gov: Follow the on-line instructions for submitting comments. • E-mail: Comments may be sent by electronic mail (e-mail) to a-and-rdocket@epa.gov, Attention Docket ID No. EPA–HQ–OAR–2008–0531. PO 00000 Frm 00003 Fmt 4702 Sfmt 4702 28451 • Fax: Fax your comments to: 202– 566–9744, Attention Docket ID No. EPA–HQ–OAR–2008–0531. • Mail: Send your comments to: Air and Radiation Docket and Information Center, Environmental Protection Agency, Mail Code 2822T, 1200 Pennsylvania Ave., NW., Washington, DC 20460. Attention Docket ID No. EPA–HQ–OAR–2008–0531. In addition, please mail a copy of your comments on the information collection provisions to the Office of Information and Regulatory Affairs, Office of Management and Budget (OMB), Attn: Desk Officer for EPA, 725 17th St., NW., Washington, DC 20503. • Hand Delivery or Courier: Deliver your comments to: EPA Docket Center, 1301 Constitution Ave., NW., Room 3334, Washington, DC. Such deliveries are only accepted during the Docket’s normal hours of operation, and special arrangements should be made for deliveries of boxed information. Instructions: Direct your comments to Docket ID No. EPA–HQ–OAR–2008– 0531. EPA’s policy is that all comments received will be included in the public docket without change and may be made available online at https:// www.regulations.gov, including any personal information provided, unless the comment includes information claimed to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Do not submit information that you consider to be CBI or otherwise protected through https:// www.regulations.gov or e-mail. The https://www.regulations.gov Web site is an ‘‘anonymous access’’ system, which means EPA will not know your identity or contact information unless you provide it in the body of your comment. If you send an e-mail comment directly to EPA without going through https:// www.regulations.gov, your e-mail address will be automatically captured and included as part of the comment that is placed in the public docket and made available on the Internet. If you submit an electronic comment, EPA recommends that you include your name and other contact information in the body of your comment and with any disk or CD–ROM you submit. If EPA cannot read your comment due to technical difficulties and cannot contact you for clarification, EPA may not be able to consider your comment. Electronic files should avoid the use of special characters, any form of encryption, and be free of any defects or viruses. For additional information about EPA’s public docket, visit the EPA E:\FR\FM\16JNP1.SGM 16JNP1

Agencies

[Federal Register Volume 74, Number 114 (Tuesday, June 16, 2009)]
[Proposed Rules]
[Pages 28449-28451]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E9-14103]


========================================================================
Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

========================================================================


Federal Register / Vol. 74, No. 114 / Tuesday, June 16, 2009 / 
Proposed Rules

[[Page 28449]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 21 and 27

[Docket No. SW021; Notice No. 27-021-SC]


Special Conditions: Robinson Helicopter Company R66 Helicopters, 
14 CFR 27.1309, Installation of an Autopilot (AP) Stabilization 
Augmentation System (SAS)

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed special conditions.

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

SUMMARY: This action proposes special conditions for installing an 
Autopilot Stabilization Augmentation System (AP/SAS) in the Robinson 
Helicopter Company (Robinson) Model R66 helicopter. This helicopter 
will have novel or unusual design features associated with installing a 
complex AP/SAS that has potential failure modes with more severe 
adverse results than those envisioned by the existing applicable 
airworthiness standards. The applicable airworthiness standards do not 
contain adequate or appropriate safety standards for this design 
feature. This proposed special condition contains the added safety 
standards the Administrator considers necessary to establish a level of 
safety equivalent to the existing airworthiness standards.

DATES: We must receive your comments by July 31, 2009.

ADDRESSES: Mail two copies of your comments to: Federal Aviation 
Administration, Rotorcraft Directorate, Attn: Rules Docket (ASW-111), 
Docket No. SW021, 2601 Meacham Blvd., Fort Worth, Texas 76137. You may 
deliver two copies to the Rotorcraft Directorate at this address. You 
must mark your comments for: Docket No. SW021. You may inspect comments 
in the Rules Docket weekdays, except Federal holidays, between 8:30 
a.m. and 4 p.m.

FOR FURTHER INFORMATION CONTACT: George Schwab, Aviation Safety 
Engineer, FAA, Rotorcraft Directorate (ASW-112), Aircraft Certification 
Service, 2601 Meacham Blvd., Fort Worth, Texas, 76137; telephone (817) 
222-5114; facsimile (817) 222-5961.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you 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 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 
on 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 additional 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 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 November 1, 2006, Robinson proposed a change to the 
certification basis, through the FAA's Los Angeles Aircraft 
Certification Office (LA ACO), that would include installing an AP/SAS 
as part of the application for type certification for the Robinson 
Model R66 helicopter. The Robinson Model R66 helicopter is a part 27 
Normal category, single turbine engine, conventional helicopter 
designed for civil operation. The helicopter is capable of carrying 
four passengers with one pilot, and has a maximum gross weight of 
approximately 2,650 pounds. The major design features include a 2-
blade, fully articulated main rotor, a 2-blade anti-torque tail rotor, 
a skid landing gear, and a visual flight rule (VFR) basic avionics 
configuration. Robinson proposes offering the Hoh Aeronautics, Inc. 
two-axis AP/SAS as a factory installed option.

Type Certification Basis

    Under 14 CFR 21.17, Robinson must show that the Model R66 
helicopter meets the applicable provisions of 14 CFR part 27, as 
amended by Amendments 27-1 through 27-40.
    If the Administrator finds the applicable airworthiness standards, 
as they apply to the type certification, do not contain adequate or 
appropriate safety standards because of a novel or unusual design 
feature, special conditions are prescribed under Sec.  21.16.
    Special conditions, as appropriate, are defined in Sec.  11.19, and 
issued by following the procedures in Sec.  11.38 and become part of 
the type certification basis under Sec.  21.17(a)(2).
    Special conditions are initially applicable to the model for which 
they are issued. Should the Type Certificate for that model be amended 
later to include any other model that incorporates the same novel or 
unusual design feature, the special condition would also apply to the 
other model under Sec.  21.101.

Novel or Unusual Design Features

    The Robinson Model R66 helicopter will be required to show 
compliance with the current applicable requirements without the 
optional AP/SAS system. The Hoh Aeronautics, Inc. AP/SAS system will 
constitute a novel or unusual design feature when installed in the 
Model R66 helicopter. Although this AP/SAS system performs non-critical 
control functions, the possible failure modes for this system and their 
effects on the ability of the helicopter to continue safe flight and 
landing are more severe than those envisioned when the present safety 
standards were promulgated. Therefore, additional safety standards are 
necessary.

Discussion

Failure Condition Categories

    The effect on safety is not adequately covered under Sec.  27.1309 
for the application of new technology and new application of standard 
technology.

[[Page 28450]]

Specifically, the present provisions of Sec.  27.1309(c) do not 
adequately address the safety requirements for systems whose failures 
could result in Catastrophic or Hazardous/Severe-Major failure 
conditions, or for complex systems whose failures could result in Major 
failure conditions.
    To comply with the provision of the special condition, we propose 
to require that Robinson provide the FAA with a Systems Safety 
Assessment (SSA) for the final Hoh Aeronautics Inc. AP/SAS installation 
configuration that will adequately address the safety objectives 
established by the Functional Hazard Assessment (FHA) and the 
Preliminary System Safety Assessment (PSSA), including the Fault Tree 
Analysis (FTA). This must ensure that all failure modes and their 
resulting effects are adequately addressed for the installed AP/SAS. 
The SSA process, FHA, PSSA, and FTA are all parts of the overall Safety 
Assessment (SA) process discussed in FAA Advisory Circular (AC) 27-1B 
(Certification of Normal Category Rotorcraft) and SAE document ARP 4761 
(Guidelines and Methods for Conducting the Safety Assessment Process on 
civil airborne Systems and Equipment).
    This special condition requires that the AP/SAS system installed on 
a Robinson Model R66 helicopter meet these requirements to adequately 
address the failure effects identified by the FHA, and subsequently 
verified by the SSA, within the defined design integrity requirements.

Applicability

    As discussed, this special condition is applicable to the Robinson 
Model R66 helicopter with the Hoh Aeronautics, Inc. AP/SAS installed as 
a factory option under the pending application for the Robinson Model 
R66 type certificate. Should Robinson Helicopter Company apply at a 
later date for a change to the type certificate to include another 
model incorporating this same factory installed option Hoh Aeronautics, 
Inc. AP/SAS novel or unusual design feature, this special condition 
would also apply to that model, under the provisions of Sec.  
21.101(b)(1).

Conclusion

    This action affects only the Robinson R66 model series of 
helicopter with the novel or unusual design features of a Hoh 
Aeronautics, Inc. AP/SAS installed. It is not a rule of general 
applicability.

List of Subjects in 14 CFR Parts 21 and 27

    Aircraft, Aviation safety, Exports, Imports, Reporting and 
recordkeeping requirements.

    The authority citation for these special conditions is as follows:

    Authority:  42 U.S.C. 7572; 49 U.S.C. 106(g), 40105, 40113, 
44701-44702, 44704, 44709, 44711, 44713, 44715, 45303.

The Proposed Special Conditions

    Accordingly, the Federal Aviation Administration (FAA) proposes 
the following special conditions as part of the type certification 
basis for Robinson Model R66 helicopters:
    For installation of a Hoh Aeronautics, Inc. Autopilot/Stability 
Augmentation System on a Robinson Model R66 helicopter, the system 
must be designed and installed so that the failure conditions 
identified in the Functional Hazard Assessment and addressed by the 
System Safety Assessment, after design completion, are adequately 
addressed in accordance with the Definitions for the Failure 
Condition Categories and the Requirements (including the design 
integrity, design environmental, and test and analysis requirements) 
of this special condition.

Definitions

    Failure Conditions are conditions that result from a failure and 
are classified, according to the severity of their effects on the 
rotorcraft, into one of the following categories:
    (1) No Effect--Failure Conditions that would have no effect on 
safety; for example, Failure Conditions that would not affect the 
operational capability of the rotorcraft or increase crew workload; 
however, could result in an inconvenience to the occupants, 
excluding the flight crew.
    (2) Minor--Failure conditions which would not significantly 
reduce rotorcraft safety, and would involve crew actions that are 
well within their capabilities. Minor failure conditions would 
include, for example, a slight reduction in safety margins or 
functional capabilities, a slight increase in crew workload such as 
routine flight plan changes, or result in some physical discomfort 
to occupants.
    (3) Major--Failure conditions which would reduce the capability 
of the rotorcraft or the ability of the crew to cope with adverse 
operating conditions to the extent there would be, for example, a 
significant reduction in safety margins or functional capabilities; 
a significant increase in crew workload or result in impairing crew 
efficiency; physical distress to occupants, including injuries; or 
physical discomfort to the flight crew.
    (4) Hazardous/Severe-Major--Failure conditions that would reduce 
the capability of the rotorcraft or the ability of the crew to cope 
with adverse operating conditions to the extent there would be:
    (i) A large reduction in safety margins or functional 
capabilities;
    (ii) Physical distress or excessive workload that would impair 
the flight crew's ability to the extent that they could not be 
relied on to perform their tasks accurately or completely; or
    (iii) Possible serious or fatal injury to a passenger or a cabin 
crewmember, excluding the flight crew.

    Note:  Hazardous/Severe-Major failure conditions can include 
events that are manageable by the crew by use of proper procedures, 
which, if not carried out correctly or in a timely manner, may 
result in a Catastrophic Event.

    (5) Catastrophic--Failure Conditions which would result in 
multiple fatalities to occupants, fatalities or incapacitation to 
the flight crew, or result in the inability of the rotorcraft to 
continue safe flight and landing.

Requirements

    Robinson must comply with the existing requirements of Sec.  
27.1309 for all applicable design and operational aspects of the AP/
SAS with the failure condition categories of No Effect, Minor, and 
for non-complex systems whose failure condition category is 
classified as Major. Robinson must also comply with the requirements 
of this special condition for all applicable design and operational 
aspects of the AP/SAS with the failure condition categories of 
Catastrophic and Hazardous/Severe-Major, and for complex systems 
classified as a Major failure condition category.
    A complex system is a system whose operations, failure modes, or 
failure effects are difficult to understand without the aid of 
analytical methods (for example, Fault Tree Analysis, Failure Modes 
and Effect Analysis, Functional Hazard Assessment, etc.).

a. Design Integrity Requirements

    Each of the failure condition categories defined in this special 
condition relate to the corresponding aircraft system integrity 
requirements. The design integrity requirements for the Hoh 
Aeronautics, Inc. AP/SAS as they relate to the allowed probability 
of occurrence for each failure condition category, and the proposed 
software design assurance level, are as follows:
    Major--Condition classified as a ``Major failure condition'' and 
resulting in Major effects must be shown to be improbable, or at or 
less than 1 x 10-5 failures/hour, and associated software 
must be developed to the RTCA/DO-178B (Software Considerations in 
Airborne Systems And Equipment Certification) software design 
assurance Level C.
    Hazardous/Severe-Major--Condition classified as a ``Hazardous/
Severe-Major failure condition'' and resulting in Hazardous/Severe-
Major effects must be shown to be extremely remote or at or less 
than 1 x 10-7 failures/hour, and associated software must 
be developed to the RTCA/DO-178B (Software Considerations in 
Airborne Systems And Equipment Certification) software design 
assurance Level B.
    Catastrophic--Condition classified as a ``Catastrophic failure 
condition'' and resulting in Catastrophic effects must be shown to 
be extremely improbable or at or less than 1 x 10-9 
failures/hour, and associated software must be developed to the

[[Page 28451]]

RTCA/DO-178B (Software Considerations in Airborne Systems And 
Equipment Certification) Level A software design assurance level.

b. Design Environmental Requirements

    Robinson must qualify the AP/SAS system equipment to the 
appropriate environmental level in the RTCA document DO-160F 
(Environmental Conditions and Test Procedures for Airborne 
Equipment), for all relevant aspects. This must show that the AP/SAS 
system performs its intended function under any foreseeable 
operating condition, which includes the expected environment in 
which the AP/SAS is intended to operate. Some of the main 
considerations for environmental concerns are installation locations 
and the resulting exposure to environmental conditions for the AP/
SAS system equipment, including considerations for other equipment 
that may be affected environmentally by the AP/SAS equipment 
installation. The level of environmental qualification must be 
related to the severity of the considered failure condition and 
effects on the aircraft.

c. Test & Analysis Requirements

    Compliance with these requirements may be shown by a variety of 
methods, which typically consist of analysis, flight tests, ground 
tests, and simulation, as a minimum. Compliance methodology is 
partly related to the associated failure condition category. If the 
AP/SAS is a complex system, compliance with the requirements for 
aspects of the AP/SAS that can result in failure conditions 
classified as Major may be shown by analysis, in combination with 
appropriate testing to validate the analysis. Compliance with the 
requirements for aspects of the AP/SAS that can result in failure 
conditions classified as Hazardous/Severe-Major may be shown by 
flight-testing in combination with analysis and simulation, and the 
appropriate testing to validate the analysis. Flight tests may be 
limited for this classification of failures due to safety 
considerations.
    Compliance with the requirements for aspects of the AP/SAS that 
can result in failure conditions classified as Catastrophic may be 
shown by analysis and validated by appropriate testing in 
combination with simulation. Very limited flight tests in 
combination with simulation may be used as a part of a showing of 
compliance for failures in this classification. Flight tests are 
performed only in circumstances that use operational variations or 
extrapolations from other flight performance aspects to address 
flight safety.

    Issued in Fort Worth, Texas, on June 11, 2009.
Mark R. Schilling,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. E9-14103 Filed 6-15-09; 8:45 am]
BILLING CODE 4910-13-P
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