Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes, 10875-10878 [2021-03483]

Download as PDF 10875 Federal Register / Vol. 86, No. 34 / Tuesday, February 23, 2021 / Proposed Rules undue risk to the NCUSIF as the 67 credit unions provided relief represent less than 1 percent of industry assets. TABLE 1—COMPLEX CREDIT UNIONS WITH A RISK BASED NET WORTH REQUIREMENT GREATER THAN 7 PERCENT Number of credit unions Asset category Assets >$50M 32 .......................................................................................................................... Assets >$500M 33 ........................................................................................................................ $50M< Assets <$500M ................................................................................................................ Therefore, this proposed rule would provide immediate relief for the 67 credit unions that must currently manage their capital levels to a riskbased net worth requirement above seven percent.34 Additionally, it would also provide relief to all credit unions with assets between $50 million and $500 million, which would be able to expand their portfolios and simply manage their capital levels to meet the seven percent leverage requirement to be well capitalized. The NCUA invites comments on all aspects of the proposal.35 V. Regulatory Procedures A. Regulatory Flexibility Act (RFA) The Regulatory Flexibility Act (RFA) generally requires that, in connection with a notice of proposed rulemaking, an agency prepare and make available for public comment an initial regulatory flexibility analysis that describes the impact of a proposed rule on small entities. A regulatory flexibility analysis is not required, however, if the agency certifies that the rule will not have a significant economic impact on a substantial number of small entities (defined for purposes of the RFA to include federally insured credit unions with assets less than $100 million) and publishes its certification and a short, explanatory statement in the Federal Register together with the rule. The proposed rule would only exempt additional credit unions from any riskbased net worth requirement in part 702 of the NCUA’s regulations applicable to complex credit unions. As a result, it 32 This reflects the current threshold for complex credit unions. 33 This reflects the proposed threshold for complex credit unions. 34 This would reduce the amount of capital they are required to hold to be well capitalized by $82 million in aggregate, based on September 30, 2020 data. 35 Because of the straightforward nature of the proposed change and the extensive comment period offered on the various RBC rulemakings, the Board is not providing the usual 60-day comment period. See NCUA Interpretive Ruling and Policy Statement (IRPS) 87–2, as amended by IRPS 03–2 and IRPS 15–1. 80 FR 57512 (Sept. 24, 2015), available at https://www.ncua.gov/files/publications/irps/ IRPS1987-2.pdf. VerDate Sep<11>2014 17:21 Feb 22, 2021 Jkt 253001 will not cause any increased burden on credit unions and will not have an impact on small credit unions. Accordingly, the NCUA certifies that the proposed rule will not have a significant economic impact on a substantial number of small credit unions. B. Paperwork Reduction Act The Paperwork Reduction Act of 1995 (PRA) applies to rulemakings in which an agency by rule creates a new paperwork burden on regulated entities or modifies an existing burden (44 U.S.C. 3507(d)). For purposes of the PRA, a paperwork burden may take the form of a reporting, recordkeeping, or a third-party disclosure requirement, referred to as an information collection. The NCUA may not conduct or sponsor, and the respondent is not required to respond to, an information collection unless it displays a valid Office of Management and Budget (OMB) control number. This proposed rule contains no provisions constituting a collection of information under the Paperwork Reduction Act of 1995 (44 U.S.C. et seq.). C. Executive Order 13132 Executive Order 13132 encourages independent regulatory agencies to consider the impact of their actions on state and local interests. The NCUA, an independent regulatory agency as defined in 44 U.S.C. 3502(5), voluntarily complies with the Executive order to adhere to fundamental federalism principles. This proposed rule would not have substantial direct effects on the states, on the relationship between the National Government and the states, or on the distribution of power and responsibilities among the various levels of government. The NCUA has therefore determined that this proposed rule does not constitute a policy that has federalism implications for purposes of the Executive order. D. Assessment of Federal Regulations and Policies on Families The NCUA has determined that this proposed rule will not affect family well-being within the meaning of PO 00000 Frm 00004 Fmt 4702 Sfmt 4702 Total assets (million) 94 27 67 Percent of industry assets $66.0 54.6 11.4 3.7 3.1 0.6 section 654 of the Treasury and General Government Appropriations Act, 1999, Public Law 105–277, 112 Stat. 2681 (1998). List of Subjects in 12 CFR Part 702 Credit, Credit unions, Reporting and recordkeeping requirements. By the NCUA Board on January 14, 2021. Melane Conyers-Ausbrooks, Secretary of the Board. For the reasons discussed in the preamble, the Board proposes to amend part 702 of chapter VII of title 12 of the Code of Federal Regulations as follows: PART 702—CAPITAL ADEQUACY 1. The authority citation for part 702 continues to read as follows: ■ Authority: 12 U.S.C. 1766(a), 1790d. § 702.103 [Amended] 2. Amend § 702.103(a) by removing the words ‘‘fifty million dollars ($50,000,000)’’ and add in their place ‘‘five hundred million dollars ($500,000,000).’’ ■ [FR Doc. 2021–01400 Filed 2–22–21; 8:45 am] BILLING CODE 7535–01–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2020–0994; Project Identifier AD–2020–00687–T] RIN 2120–AA64 Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: The FAA proposes to adopt a new airworthiness directive (AD) for certain Gulfstream Aerospace Corporation (Gulfstream) Model GVII– G600 airplanes. This proposed AD was prompted by a report that a failure mode SUMMARY: E:\FR\FM\23FEP1.SGM 23FEP1 10876 Federal Register / Vol. 86, No. 34 / Tuesday, February 23, 2021 / Proposed Rules in the data concentration network (DCN) software causes the pitch attitude value to freeze on the primary flight display (PFD) for up to 20 seconds. This proposed AD would require updating the DCN and flight deck master operating system (MOS) software. The FAA is proposing this AD to address the unsafe condition on these products. DATES: The FAA must receive comments on this proposed AD by April 9, 2021. ADDRESSES: You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: • Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments. • Fax: (202) 493–2251. • Mail: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE, Washington, DC 20590. • Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. For service information identified in this proposed rule, contact Gulfstream Aerospace Corporation, Technical Publications Dept., P.O. Box 2206, Savannah, GA 31402; phone: (800) 810– 4853; email: pubs@gulfstream.com; website: https://www.gulfstream.com/ en/customer-support/. You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 901 Locust, Kansas City, Missouri 64106. For information on the availability of this material at the FAA, call (816) 329– 4148. Examining the AD Docket You may examine the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA–2020–0994; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this NPRM, any comments received, and other information. The street address for Docket Operations is listed above. FOR FURTHER INFORMATION CONTACT: Myles Jalalian, Aviation Safety Engineer, Atlanta ACO Branch, FAA, 1701 Columbia Avenue, College Park, GA 30337; phone: (404) 474–5572; fax: (404) 474–5606; email: myles.jalalian@ faa.gov. SUPPLEMENTARY INFORMATION: Comments Invited The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send VerDate Sep<11>2014 17:21 Feb 22, 2021 Jkt 253001 your comments to an address listed under ADDRESSES. Include ‘‘Docket No. FAA–2020–0994; Project Identifier AD– 2020–00687–T’’ at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this proposal because of those comments. Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to https:// www.regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM. Confidential Business Information CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this AD contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this AD, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as ‘‘PROPIN.’’ The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this AD. Submissions containing CBI should be sent to Myles Jalalian, Aviation Safety Engineer, Atlanta ACO Branch, FAA, 1701 Columbia Avenue, College Park, GA 30337. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking. Background The FAA received a report that on certain Gulfstream Model GVII–G600 airplanes a failure mode in the DCN software causes the pitch attitude value to freeze on the PFD for up to 20 seconds. During implementation of the DCN software update version 10.10.10 for certain Model GVII–G500 airplane configurations (‘‘Block 1’’), it was discovered the software supplier had incorrectly implemented one of Gulfstream’s design requirements. At the time of this discovery on Model GVII–G500 Block 1 configurations, the PO 00000 Frm 00005 Fmt 4702 Sfmt 4702 DCN software version 10.10.10 had already been implemented on Model GVII–G600 airplanes in service. This airplane has three independent inertial reference systems (IRSs), identified as IRS1, IRS2, and IRS3, which are expected to provide identical pitch data. During flight testing, the GVII–G600 IRS1 was found to indicate a slightly different pitch from IRS2 and IRS3, at the same actual airplane pitch attitude. A DCN embedded function was created to correct the very minor pitch difference between IRS1, IRS2, and IRS3. DCN software version 10.10.10 implemented the new embedded function which computes a ‘‘PITCH_ DELTA correction factor’’ (pitch difference correction factor) between the IRS pitch angles being used by the PFDs. The system calculates pitch correction based in part on the IRS1 pitch angle. If the IRS1 is lost, it causes the embedded function to invalidate the ‘‘PITCH_DELTA output.’’ During this failure mode, the pitch attitude value freezes on the display for up to 20 seconds, which results in temporarily incorrect pitch indications. The effect is evident only if the pitch of the airplane changes during the 20 second reset window. After 20 seconds, the system returns to normal. The standby flight display and heads up display are unaffected by this failure mode and continue to display the correct pitch attitude. There is not an alert or annunciation that informs the flight crew of a stale (frozen) pitch display or potentially misleading flight information. This condition, if not addressed, could result in loss of control of the airplane in certain phases of flight during instrument meteorological conditions. Related Service Information Under 1 CFR Part 51 The FAA reviewed Gulfstream GVII– G600 Aircraft Service Change No. 901, Initial Issue, dated May 12, 2020. This service document specifies procedures for installing the MOS software update part number EB60001034–0106 and operationally checking the installation. The FAA also reviewed Gulfstream GVII–G600 Aircraft Service Change No. 020, Initial Issue, dated May 12, 2020. This service document specifies procedures for updating the DCN software level to version 10.10.12, updating system software in support of the MOS software update, and operationally checking the installation. This service information is reasonably available because the interested parties have access to it through their normal E:\FR\FM\23FEP1.SGM 23FEP1 Federal Register / Vol. 86, No. 34 / Tuesday, February 23, 2021 / Proposed Rules course of business or by the means identified in the ADDRESSES section. Proposed AD Requirements in This NPRM FAA’s Determination The FAA is issuing this NPRM after determining the unsafe condition described previously is likely to exist or develop in other products of the same type design. This proposed AD would require accomplishing the actions specified in the service information described previously. 10877 Costs of Compliance The FAA estimates that this AD, if adopted as proposed, would affect 43 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD: ESTIMATED COSTS Action Labor cost Update DNC software ............ Update MOS software ............ 30 work-hours × $85 per hour = $2,550 ................................ 10 work-hours × $85 per hour = $850 ................................... The FAA has included all known costs in its cost estimate. According to the manufacturer, however, some of the costs of this proposed AD may be covered under warranty, thereby reducing the cost impact on affected operators. Authority for This Rulemaking Title 49 of the United States Code specifies the FAA’s authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII: Aviation Programs, describes in more detail the scope of the Agency’s authority. The FAA is proposing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701: General requirements. Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. Regulatory Findings The FAA determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. For the reasons discussed above, I certify this proposed regulation: (1) Is not a ‘‘significant regulatory action’’ under Executive Order 12866, (2) Would not affect intrastate aviation in Alaska, and VerDate Sep<11>2014 17:21 Feb 22, 2021 Jkt 253001 Parts cost (3) Would not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. The Proposed Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows: PART 39—AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows: ■ Authority: 49 U.S.C. 106(g), 40113, 44701. § 39.13 [Amended] 2. The FAA amends § 39.13 by adding the following new airworthiness directive: ■ Gulfstream Aerospace Corporation: Docket No. FAA–2020–0994; Project Identifier AD–2020–00687–T. (a) Comments Due Date The FAA must receive comments on this airworthiness directive (AD) by April 9, 2021. (b) Affected ADs None. (c) Applicability This AD applies to Gulfstream Aerospace Corporation Model GVII–G600 airplanes, serial numbers 73001 through 73043, certificated in any category. (d) Subject Joint Aircraft System Component Code 3400, Navigation System. (e) Unsafe Condition This AD was prompted by reports of software causing pitch attitude value freezing on the Primary Flight Display (PFD) for up PO 00000 Frm 00006 Fmt 4702 Sfmt 4702 $52 52 Cost per product $2,602 902 Cost on U.S. operators $111,886 38,786 to 20 seconds. The FAA is issuing this AD to prevent a stale pitch display or potentially misleading flight information. The unsafe condition, if not addressed, could result in loss of control of the airplane in certain phases of flight during instrument meteorological conditions. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Update Software Within 24 months after the effective date of this AD, update the data concentration network and flight deck master operating system software by using the Modification Instructions, Steps III. A through I, in Gulfstream GVII–G600 Aircraft Service Change No. 901, Initial Issue, dated May 12, 2020, concurrently with the Modification Instructions, Steps III. A through D, in Gulfstream GVII–G600 Aircraft Service Change No. 020, Initial Issue, dated May 12, 2020. (h) Alternative Methods of Compliance (AMOCs) (1) The Manager, Atlanta ACO Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the certification office, send it to the attention of the person identified in Related Information. (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/ certificate holding district office. (i) Related Information (1) For more information about this AD, contact Myles Jalalian, Aviation Safety Engineer, Atlanta ACO Branch, FAA, 1701 Columbia Avenue, College Park, GA 30337; phone: (404) 474–5572; fax: (404) 474–5606; email: myles.jalalian@faa.gov. (2) For service information identified in this AD, contact Gulfstream Aerospace Corporation, Technical Publications Dept., P.O. Box 2206, Savannah, GA 31402; phone: E:\FR\FM\23FEP1.SGM 23FEP1 10878 Federal Register / Vol. 86, No. 34 / Tuesday, February 23, 2021 / Proposed Rules (800) 810–4853; email: pubs@ gulfstream.com; website: https:// www.gulfstream.com/en/customer-support/. You may view this referenced service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 901 Locust, Kansas City, Missouri 64106. For information on the availability of this material at the FAA, call (816) 329–4148. Issued on January 29, 2021. Gaetano A. Sciortino, Deputy Director for Strategic Initiatives, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2021–03483 Filed 2–22–21; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 Examining the AD Docket [Docket No. FAA–2021–0022; Project Identifier MCAI–2020–00395–E] RIN 2120–AA64 Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG (Type Certificate Previously Held by RollsRoyce plc) Turbofan Engines Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: The FAA proposes to adopt a new airworthiness directive (AD) for all Rolls-Royce Deutschland Ltd & Co KG (RRD) Trent XWB–75, Trent XWB–79, Trent XWB–79B, Trent XWB–84, and Trent XWB–97 model turbofan engines. This proposed AD was prompted by the manufacturer revising the time limits manual (TLM) to incorporate repairs to the low-pressure compressor (LPC) blades and introduce a new fan blade inspection. This proposed AD would require revisions to the airworthiness limitations section (ALS) of the RollsRoyce (RR) Trent XWB TLM and the operator’s existing approved aircraft maintenance program (AMP). The FAA is proposing this AD to address the unsafe condition on these products. DATES: The FAA must receive comments on this proposed AD by April 9, 2021. ADDRESSES: You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: • Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments. • Fax: (202) 493–2251. • Mail: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room SUMMARY: VerDate Sep<11>2014 17:21 Feb 22, 2021 Jkt 253001 W12 140, 1200 New Jersey Avenue SE, Washington, DC 20590. • Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. For service information identified in this NPRM, contact Rolls-Royce plc, Corporate Communications, P.O. Box 31, Derby, DE24 8BJ, United Kingdom; phone: +44 (0)1332 242424; fax: +44 (0)1332 249936; email: https:// www.rolls-royce.com/contact-us/civilaerospace.aspx; website: https:// www.rolls-royce.com/contact-us.aspx. You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 1200 District Avenue, Burlington, MA 01803. For information on the availability of this material at the FAA, call (781) 238–7759. You may examine the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA–2021–0022; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this NPRM, the mandatory continuing airworthiness information (MCAI), any comments received, and other information. The street address for Docket Operations is listed above. FOR FURTHER INFORMATION CONTACT: Scott Stevenson, Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: (781) 238–7132; fax: (781) 238– 7199; email: Scott.M.Stevenson@faa.gov. SUPPLEMENTARY INFORMATION: Comments Invited The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under ADDRESSES. Include ‘‘Docket No. FAA–2021–0022; Project Identifier MCAI–2020–00395–E’’ at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this proposal because of those comments. Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to https:// www.regulations.gov, including any personal information you provide. The PO 00000 Frm 00007 Fmt 4702 Sfmt 4702 agency will also post a report summarizing each substantive verbal contact received about this NPRM. Confidential Business Information CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as ‘‘PROPIN.’’ The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Scott Stevenson, Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking. Background The European Union Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community, has issued EASA AD 2020–0066, dated March 23, 2020 (referred to after this as ‘‘the MCAI’’), to address the unsafe condition on these products. The MCAI states: The Airworthiness Limitations Section instructions for Trent XWB engines, which are approved by EASA, are defined and published in TLM TRENTXWB–K0680– TIME0–01. These instructions have been identified as mandatory for continued airworthiness. Failure to accomplish these instructions could result in an unsafe condition. Rolls-Royce recently revised the TLM, introducing new and/or more restrictive instructions. For the reason described above, this [EASA] AD requires accomplishment of the instructions specified in the TLM, as defined in this AD. You may obtain further information by examining the MCAI in the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA–2021–0022. FAA’s Determination This product has been approved by EASA and is approved for operation in the United States. Pursuant to our bilateral agreement with the European Community, EASA has notified the FAA E:\FR\FM\23FEP1.SGM 23FEP1

Agencies

[Federal Register Volume 86, Number 34 (Tuesday, February 23, 2021)]
[Proposed Rules]
[Pages 10875-10878]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-03483]


=======================================================================
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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0994; Project Identifier AD-2020-00687-T]
RIN 2120-AA64


Airworthiness Directives; Gulfstream Aerospace Corporation 
Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain Gulfstream Aerospace Corporation (Gulfstream) Model GVII-
G600 airplanes. This proposed AD was prompted by a report that a 
failure mode

[[Page 10876]]

in the data concentration network (DCN) software causes the pitch 
attitude value to freeze on the primary flight display (PFD) for up to 
20 seconds. This proposed AD would require updating the DCN and flight 
deck master operating system (MOS) software. The FAA is proposing this 
AD to address the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by April 9, 
2021.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: (202) 493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this proposed rule, contact 
Gulfstream Aerospace Corporation, Technical Publications Dept., P.O. 
Box 2206, Savannah, GA 31402; phone: (800) 810-4853; email: 
[email protected]; website: https://www.gulfstream.com/en/customer-support/. You may view this service information at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 901 Locust, 
Kansas City, Missouri 64106. For information on the availability of 
this material at the FAA, call (816) 329-4148.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2020-0994; or in person at 
Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The AD docket contains this NPRM, any comments 
received, and other information. The street address for Docket 
Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Myles Jalalian, Aviation Safety 
Engineer, Atlanta ACO Branch, FAA, 1701 Columbia Avenue, College Park, 
GA 30337; phone: (404) 474-5572; fax: (404) 474-5606; email: 
[email protected].

SUPPLEMENTARY INFORMATION: 

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under ADDRESSES. Include ``Docket No. FAA-2020-0994; Project Identifier 
AD-2020-00687-T'' at the beginning of your comments. The most helpful 
comments reference a specific portion of the proposal, explain the 
reason for any recommended change, and include supporting data. The FAA 
will consider all comments received by the closing date and may amend 
this proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
https://www.regulations.gov, including any personal information you 
provide. The agency will also post a report summarizing each 
substantive verbal contact received about this NPRM.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this AD contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or responsive to 
this AD, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and they will not be placed in the public 
docket of this AD. Submissions containing CBI should be sent to Myles 
Jalalian, Aviation Safety Engineer, Atlanta ACO Branch, FAA, 1701 
Columbia Avenue, College Park, GA 30337. Any commentary that the FAA 
receives which is not specifically designated as CBI will be placed in 
the public docket for this rulemaking.

Background

    The FAA received a report that on certain Gulfstream Model GVII-
G600 airplanes a failure mode in the DCN software causes the pitch 
attitude value to freeze on the PFD for up to 20 seconds.
    During implementation of the DCN software update version 10.10.10 
for certain Model GVII-G500 airplane configurations (``Block 1''), it 
was discovered the software supplier had incorrectly implemented one of 
Gulfstream's design requirements. At the time of this discovery on 
Model GVII-G500 Block 1 configurations, the DCN software version 
10.10.10 had already been implemented on Model GVII-G600 airplanes in 
service. This airplane has three independent inertial reference systems 
(IRSs), identified as IRS1, IRS2, and IRS3, which are expected to 
provide identical pitch data. During flight testing, the GVII-G600 IRS1 
was found to indicate a slightly different pitch from IRS2 and IRS3, at 
the same actual airplane pitch attitude. A DCN embedded function was 
created to correct the very minor pitch difference between IRS1, IRS2, 
and IRS3. DCN software version 10.10.10 implemented the new embedded 
function which computes a ``PITCH_DELTA correction factor'' (pitch 
difference correction factor) between the IRS pitch angles being used 
by the PFDs. The system calculates pitch correction based in part on 
the IRS1 pitch angle. If the IRS1 is lost, it causes the embedded 
function to invalidate the ``PITCH_DELTA output.'' During this failure 
mode, the pitch attitude value freezes on the display for up to 20 
seconds, which results in temporarily incorrect pitch indications. The 
effect is evident only if the pitch of the airplane changes during the 
20 second reset window. After 20 seconds, the system returns to normal. 
The standby flight display and heads up display are unaffected by this 
failure mode and continue to display the correct pitch attitude.
    There is not an alert or annunciation that informs the flight crew 
of a stale (frozen) pitch display or potentially misleading flight 
information.
    This condition, if not addressed, could result in loss of control 
of the airplane in certain phases of flight during instrument 
meteorological conditions.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Gulfstream GVII-G600 Aircraft Service Change No. 
901, Initial Issue, dated May 12, 2020. This service document specifies 
procedures for installing the MOS software update part number 
EB60001034-0106 and operationally checking the installation.
    The FAA also reviewed Gulfstream GVII-G600 Aircraft Service Change 
No. 020, Initial Issue, dated May 12, 2020. This service document 
specifies procedures for updating the DCN software level to version 
10.10.12, updating system software in support of the MOS software 
update, and operationally checking the installation.
    This service information is reasonably available because the 
interested parties have access to it through their normal

[[Page 10877]]

course of business or by the means identified in the ADDRESSES section.

FAA's Determination

    The FAA is issuing this NPRM after determining the unsafe condition 
described previously is likely to exist or develop in other products of 
the same type design.

Proposed AD Requirements in This NPRM

    This proposed AD would require accomplishing the actions specified 
in the service information described previously.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 43 airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Update DNC software...................  30 work-hours x $85 per              $52          $2,602        $111,886
                                         hour = $2,550.
Update MOS software...................  10 work-hours x $85 per               52             902          38,786
                                         hour = $850.
----------------------------------------------------------------------------------------------------------------

    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, some of the costs of this 
proposed AD may be covered under warranty, thereby reducing the cost 
impact on affected operators.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII: Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    The FAA is proposing this rulemaking under the authority described 
in Subtitle VII, Part A, Subpart III, Section 44701: General 
requirements. Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    The FAA determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would not 
have a substantial direct effect on the States, on the relationship 
between the national government and the States, or on the distribution 
of power and responsibilities among the various levels of government.
    For the reasons discussed above, I certify this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Would not affect intrastate aviation in Alaska, and
    (3) Would not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

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


Sec.  39.13  [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

Gulfstream Aerospace Corporation: Docket No. FAA-2020-0994; Project 
Identifier AD-2020-00687-T.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by April 9, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Gulfstream Aerospace Corporation Model GVII-
G600 airplanes, serial numbers 73001 through 73043, certificated in 
any category.

(d) Subject

    Joint Aircraft System Component Code 3400, Navigation System.

(e) Unsafe Condition

    This AD was prompted by reports of software causing pitch 
attitude value freezing on the Primary Flight Display (PFD) for up 
to 20 seconds. The FAA is issuing this AD to prevent a stale pitch 
display or potentially misleading flight information. The unsafe 
condition, if not addressed, could result in loss of control of the 
airplane in certain phases of flight during instrument 
meteorological conditions.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Update Software

    Within 24 months after the effective date of this AD, update the 
data concentration network and flight deck master operating system 
software by using the Modification Instructions, Steps III. A 
through I, in Gulfstream GVII-G600 Aircraft Service Change No. 901, 
Initial Issue, dated May 12, 2020, concurrently with the 
Modification Instructions, Steps III. A through D, in Gulfstream 
GVII-G600 Aircraft Service Change No. 020, Initial Issue, dated May 
12, 2020.

(h) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Atlanta ACO Branch, FAA, has the authority to 
approve AMOCs for this AD, if requested using the procedures found 
in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request 
to your principal inspector or local Flight Standards District 
Office, as appropriate. If sending information directly to the 
manager of the certification office, send it to the attention of the 
person identified in Related Information.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(i) Related Information

    (1) For more information about this AD, contact Myles Jalalian, 
Aviation Safety Engineer, Atlanta ACO Branch, FAA, 1701 Columbia 
Avenue, College Park, GA 30337; phone: (404) 474-5572; fax: (404) 
474-5606; email: [email protected].
    (2) For service information identified in this AD, contact 
Gulfstream Aerospace Corporation, Technical Publications Dept., P.O. 
Box 2206, Savannah, GA 31402; phone:

[[Page 10878]]

(800) 810-4853; email: [email protected]; website: https://www.gulfstream.com/en/customer-support/. You may view this 
referenced service information at the FAA, Airworthiness Products 
Section, Operational Safety Branch, 901 Locust, Kansas City, 
Missouri 64106. For information on the availability of this material 
at the FAA, call (816) 329-4148.

    Issued on January 29, 2021.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-03483 Filed 2-22-21; 8:45 am]
BILLING CODE 4910-13-P

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