Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes, 45705-45710 [2017-20831]

Download as PDF Federal Register / Vol. 82, No. 189 / Monday, October 2, 2017 / Rules and Regulations Adoption of the Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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 (AD): ■ 2017–20–07 Bombardier, Inc.: Amendment 39–19064; Docket No. FAA–2017–0518; Product Identifier 2016–NM–167–AD. (a) Effective Date This AD is effective November 6, 2017. (b) Affected ADs None. (c) Applicability This AD applies to Bombardier, Inc., Model DHC–8–400, –401, and –402 airplanes, certificated in any category, serial numbers 4001, and 4003 through 4504 inclusive. (d) Subject Air Transport Association (ATA) of America Code 26, Fire protection. (e) Reason This AD was prompted by the failure of the fire control amplifier (FCA), which was likely caused by an electrical short in a discharged squib for a fire extinguishing bottle. We are issuing this AD to prevent failure of the FCA and subsequent discharge of fire extinguishing bottles and false fire indications, leaving the flight crew with reduced firefighting capability in the event of a fire. jstallworth on DSKBBY8HB2PROD with RULES (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Replacement of Affected Circuit Breakers Within 6,000 flight hours or 3 years, whichever occurs first, after the effective date of this AD: Replace the 7.5-amp circuit breakers specified in Bombardier Service Bulletin 84–26–16, Revision A, dated February 12, 2016, with 1-amp circuit breakers having part number MS3320–1, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 84–26–16, Revision A, dated February 12, 2016. (h) Credit for Previous Actions This paragraph provides credit for actions required by paragraph (g) of this AD, if those actions were performed before the effective date of this AD using Bombardier Service Bulletin 84–26–16, dated August 14, 2015. VerDate Sep<11>2014 15:21 Sep 29, 2017 Jkt 244001 (i) Other FAA AD Provisions The following provisions also apply to this AD: (1) Alternative Methods of Compliance (AMOCs): The Manager, New York 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 ATTN: Program Manager, Continuing Operational Safety, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516–228–7300; fax 516–794–5531. 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. (2) Contacting the Manufacturer: For any requirement in this AD to obtain corrective actions from a manufacturer, the action must be accomplished using a method approved by the Manager, New York ACO Branch, FAA; or Transport Canada Civil Aviation (TCCA); or Bombardier, Inc.’s TCCA Design Approval Organization (DAO). If approved by the DAO, the approval must include the DAO-authorized signature. (j) Related Information (1) Refer to Mandatory Continuing Airworthiness Information (MCAI) Canadian Airworthiness Directive CF–2016–25, dated August 22, 2016, for related information. This MCAI may be found in the AD docket on the Internet at https://www.regulations.gov by searching for and locating Docket No. FAA–2017–0518. (2) For more information about this AD, contact Assata Dessaline, Aerospace Engineer, Avionics and Administrative Services Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516–228– 7301; fax 516–794–5531. (3) Service information identified in this AD that is not incorporated by reference is available at the addresses specified in paragraphs (k)(3) and (k)(4) of this AD. (k) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this service information as applicable to do the actions required by this AD, unless this AD specifies otherwise. (i) Bombardier Service Bulletin 84–26–16, Revision A, dated February 12, 2016. (ii) Reserved. (3) For service information identified in this AD, contact Bombardier, Inc., Q-Series Technical Help Desk, 123 Garratt Boulevard, Toronto, Ontario M3K 1Y5, Canada; telephone 416–375–4000; fax 416–375–4539; email thd.qseries@aero.bombardier.com; Internet https://www.bombardier.com. (4) You may view this service information at the FAA, Transport Standards Branch, PO 00000 Frm 00027 Fmt 4700 Sfmt 4700 45705 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425–227–1221. (5) You may view this service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202–741–6030, or go to: https:// www.archives.gov/federal-register/cfr/ibrlocations.html. Issued in Renton, Washington, on September 20, 2017. Dionne Palermo, Acting Director, System Oversight Division, Aircraft Certification Service. [FR Doc. 2017–20824 Filed 9–29–17; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2016–9522; Product Identifier 2016–NM–144–AD; Amendment 39–19065; AD 2017–20–08] RIN 2120–AA64 Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Final rule. AGENCY: We are superseding Airworthiness Directive (AD) 2009–17– 01, which applied to certain Gulfstream Model G–IV, GIV–X, GV–SP airplanes and Model GV airplanes. AD 2009–17– 01 required an inspection for sealant applied to the exterior of the auxiliary power unit (APU) enclosure (firewall), and a revision of the airplane flight manual (AFM), as applicable. This AD requires revising the AFM and revising the applicability to include additional airplanes. This AD was prompted by a report indicating that the type design sealant applied to the APU enclosure failed certain tests. We are issuing this AD to address the unsafe condition on these products. DATES: This AD is effective November 6, 2017. The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of November 6, 2017. ADDRESSES: For service information identified in this final rule, contact Gulfstream Aerospace Corporation, Technical Publications Dept., P.O. Box 2206, Savannah, GA 31402–2206; telephone 800–810–4853; fax 912–965– 3520; email pubs@gulfstream.com; Internet https://www.gulfstream.com/ SUMMARY: E:\FR\FM\02OCR1.SGM 02OCR1 45706 Federal Register / Vol. 82, No. 189 / Monday, October 2, 2017 / Rules and Regulations product_support/technical_pubs/pubs/ index.htm. You may view this referenced service information at the FAA, Transport Standards Branch, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425–227–1221. It is also available on the Internet at https://www.regulations.gov by searching for and locating Docket No. FAA–2016– 9522. Examining the AD Docket You may examine the AD docket on the Internet at https:// www.regulations.gov by searching for and locating Docket No. FAA–2016– 9522; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the regulatory evaluation, any comments received, and other information. The address for the Docket Office (phone: 800–647–5527) is Docket Management Facility, U.S. Department of Transportation, Docket Operations, M–30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590. FOR FURTHER INFORMATION CONTACT: Ky Phan, Aerospace Engineer, Propulsion and Services Section, FAA, Atlanta ACO Branch, 1701 Columbia Avenue, College Park, GA 30337; phone: 404– 474–5536; fax: 404–474–5606; email: ky.phan@faa.gov. SUPPLEMENTARY INFORMATION: jstallworth on DSKBBY8HB2PROD with RULES Discussion We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2009–17–01, Amendment 39–15991 (74 FR 40061, August 11, 2009) (‘‘AD 2009–17–01’’). AD 2009–17–01 applied to certain Gulfstream Model G–IV, GIV–X, GV–SP airplanes, and Model GV airplanes. The NPRM published in the Federal Register on January 4, 2017 (82 FR 737) (‘‘the NPRM’’). The NPRM was prompted by a report indicating that the type design sealant (Aerospace Material Specification (AMS) 3374), applied to the APU enclosure, does not meet the requirement in 14 CFR 25.1191(b)(1) for a firewall to be fireproof, and failed a certification test and a company test. The NPRM proposed to require revising the AFM and revising the applicability to include additional airplanes. We are issuing this AD to provide the flight crew with operating procedures for airplanes that have AMS 3374 or Gulfstream Material Specification (GMS) 4107 sealant applied to the APU enclosure (firewall). Under certain VerDate Sep<11>2014 15:21 Sep 29, 2017 Jkt 244001 anomalous conditions such as an APU failure/APU compartment fire, AMS 3374 or GMS 4107 sealant could ignite the exterior surfaces of the APU enclosure, and result in propagation of an uncontained fire to other critical areas of the airplane. Comments We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the NPRM and the FAA’s response to each comment. Request To Withdraw the NPRM Gulfstream requested that the NPRM be withdrawn. The commenter stated that the FAA’s findings and decisions in the proposed AD are not based on analysis of the commenter’s supporting data and accepted risk and safety assessment methodologies. The commenter asserted that its risk assessments, performed using the FAA’s Transport Airplane Risk Assessment Methodology (TARAM) Handbook, are within the allowable guidelines of the FAA’s TARAM Handbook. We do not agree with the commenter’s request because this final rule is consistent with FAA policy and orders. The FAA’s TARAM is used to assess risk associated with a wide variety of potential safety issues. The FAA typically follows the defined risk guidelines contained in the TARAM Handbook for transport category airplanes. However, occasionally, other factors affect the decision on whether to issue an AD. FAA Order 8110.107A, ‘‘Monitor Safety/Analyze Data,’’ paragraph 2–10.e. states: In rare situations the Aviation Safety Engineer or FAA management may, based on factors unrelated to the risk analysis, make recommendations not consistent with risk guidelines for ADs or other mandatory corrective actions. The decision to accept or reject these recommendations is made during the CARB [Corrective Action Review Board]. One such factor, unrelated to risk analysis, is whether the affected system provides an emergency or safety function. Examples of emergency/safety systems include seatbelts, life rafts, oxygen systems, and firewalls. Failure of emergency systems typically do not cause an accident, but can greatly increase the probability of fatalities in the event of an additional unrelated failure. TARAM analyses of emergency/ safety systems typically indicate a low TARAM risk. This is due to the fact that the precipitating event is very rare, for example, high-g decelerations due to an accident, ditching, explosive decompression, and engine fire. Ultimately, the decision regarding PO 00000 Frm 00028 Fmt 4700 Sfmt 4700 whether to mandate airworthiness action for a condition is the responsibility of the FAA’s CARB, which for this AD was comprised of representatives from the Atlanta ACO Branch, Transport Airplane Directorate, Atlanta MIDO Section, and the Aircraft Evaluation Group. The CARB unanimously concluded that factors other than the TARAM risk indicated the need to mandate corrective action for Gulfstream APU firewalls assembled using AMS 3374 sealant, in addition to the previously mandated requirements for Gulfstream APU firewalls assembled using GMS 4107 sealant. Several 14 CFR part 25 regulations are intended to prevent the spread of a fire to other critical areas of an airplane in the event of an in-flight or ground fire; one of these regulations is 14 CFR 25.1191 (‘‘Firewalls’’). The 14 CFR part 25 regulations include requirements for (1) fire detection, (2) fire suppression, and (3) fire containment by a firewall. The AMS 3374 sealant, as applied to the Gulfstream APU firewall type designs that are the subject of this AD, has been shown by fire testing to result in backside (cold side) ignition of the firewall when exposed to a 2,000 degree Fahrenheit flame for 15 minutes, thus violating the 14 CFR part 25 requirement for the firewall to be fireproof (refer to FAA Advisory Circular (AC) 20–135, ‘‘Powerplant Installation and Propulsion System Component Fire Protection Test Methods, Standards and Criteria,’’ dated February 6, 1990 (‘‘AC 20–135’’), for firewall fire testing guidance.) Previous fire testing also confirmed that Gulfstream APU firewalls assembled with GMS 4107 exhibited backside ignition during those tests. The backside ignition of the Gulfstream APU firewalls occurred in an area of the airplane that does not have fire detection or fire suppression. This is a non-compliance with the requirements of 14 CFR 25.1191(b)(1) for firewalls to be fireproof. If an APU fire occurred in flight or on the ground on such a noncompliant airplane, it could result in backside ignition of the firewall, potentially resulting in propagation of an uncontained fire to other critical areas of the airplane. The area outside and adjacent to the Gulfstream APU firewall contains many airplane critical systems such as empennage structure, flight control components, fuel lines, and oil lines. The FAA finds that APU operations on the affected Gulfstream models without a firewall that is fireproof, as required by 14 CFR 25.1191, constitutes an unsafe condition. The FAA performed an E:\FR\FM\02OCR1.SGM 02OCR1 Federal Register / Vol. 82, No. 189 / Monday, October 2, 2017 / Rules and Regulations additional TARAM analysis, which indicated a higher risk than the results of the original Gulfstream TARAM analysis. However, we want to point out that neither TARAM analysis was the sole consideration for mandating corrective action. We have made no changes to this AD in this regard. jstallworth on DSKBBY8HB2PROD with RULES Request for Separate AD Action for AMS 3374 Sealant Gulfstream requested that the FAA issue a separate rulemaking action to address the use of AMS 3374 sealant. The commenter deems it inaccurate to associate the GMS 4107 sealant unsafe condition with the application of the AMS 3374 sealant. Gulfstream also considers the corrective actions to be significantly different for the two types of sealants. We disagree with the commenter’s request. Many of the Gulfstream airplanes affected by this AD have both GMS 4107 and AMS 3374 sealants used in the fabrication of APU firewalls. The use of GMS 4107 and/or AMS 3374 sealants, per the Gulfstream type design for the APU firewalls that are the subject of this AD action, has resulted in backside ignition of the APU firewall in fire tests that were intended to demonstrate that the firewalls are fireproof. The corrective action for both types of sealants is identical, applying restrictions on APU operations. The corrective actions specified in the AD being superseded, AD 2009–17–01, did not address APU firewalls fabricated using AMS 3374 sealant. Subsequent fire testing has shown that AMS 3374 sealant, used as specified in the Gulfstream type design, does not comply with the regulations that require a firewall to be fireproof; therefore, AD 2009–17–01 must be superseded to include APU firewalls fabricated using AMS 3374 sealant. Future rulemaking to incorporate a solution proposed by Gulfstream might be considered when and if a proposed solution is made available to the FAA. We have made no changes to this AD in this regard. Request To Clarify Terminology Gulfstream requested that the FAA revise the NPRM by removing all of the statements that AMS 3374 sealant is flammable. The commenter stated that it is not accurate to make a general statement that AMS 3374 sealant is flammable because there are many applications where AMS 3374 sealants are compliant with applicable fireproof certification requirements. We partially agree with the commenter’s request. The FAA’s certification requirement is that firewalls be fireproof, not that the VerDate Sep<11>2014 15:21 Sep 29, 2017 Jkt 244001 sealant be fireproof. The FAA does not have specific requirements for sealant, apart from the requirement that its use in the assembly of firewalls must result in a fireproof firewall assembly. Also, the commenter’s statement that there are many applications where AMS 3374 sealants are compliant with applicable fireproof certification requirements may be partially correct. There could be firewalls assembled using AMS 3374 sealants that do meet the applicable fireproof certification requirements. The issue addressed by this final rule is that Gulfstream’s application of AMS 3374 sealant to the APU firewall assemblies affected by this rulemaking action is not compliant with the airworthiness requirement for the firewall to be fireproof. The AMS 3374 sealant does meet the requirements of an industry specification, the Society of Automotive Engineers (SAE) Standard AMS 3374. Compliance with an SAE standard is not equivalent to, and does not satisfy, compliance with the FAA certification requirement that firewalls be fireproof. AC 20–135 is used throughout the aviation industry as guidance material for how to show compliance with the FAA’s requirement that firewalls be fireproof. Regarding the use of sealants, AC 20–135 provides the following guidance: Outgassing. A characteristic of bonded construction firewall materials and seal materials is the outgassing of the volatile constituents of the bonding resins or seal materials. This can occur from either the hot or cool side surface of the specimens during the test. These gasses are, in most instances, highly flammable. Ignition occurring on the cool side is unacceptable in passing the fire test. . . . For these types of construction, no ‘‘cool side’’ ignition is allowed and verification is required. There are many variables that determine if a given firewall configuration meets the airworthiness requirement to be fireproof. Sealants are known to outgas volatile constituents. In the case of the Gulfstream APU firewall type design, outgassed constituents of AMS 3374 sealant ignited on the backside during fire testing, and therefore, the firewall does not meet the definition of fireproof per AC 20–135. We have changed the wording in this final rule to specify that the type design sealant (AMS 3374), as applied in the Gulfstream APU firewall, does not meet the airworthiness requirement in 14 CFR 25.1191(b)(1), for a firewall to be fireproof. We do not agree that AMS 3374 sealant is compliant with applicable fireproof certification requirements because the FAA does not certificate sealants; the FAA certificates that firewalls are fireproof. Therefore, we PO 00000 Frm 00029 Fmt 4700 Sfmt 4700 45707 have made no changes to this AD in this regard. Request To Revise the Estimated Costs of Compliance Gulfstream requested that the estimated costs of compliance in the NPRM be revised to include costs associated with an operator’s inability to use the APU during normal operations, and the cost associated with a terminating action. The commenter noted that the estimated costs in the NPRM are associated with physically revising the AFM by inserting the applicable AFM supplement (AFMS). The commenter stated that the costs associated with a terminating action that would allow an operator to use its APU in flight is much more expensive, and depending on the number of airplanes that need to be retrofitted, the costs are likely to be tens of millions of dollars. The FAA did not include any costs associated with an operator’s inability to use the APU during normal operations because APU usage is not required by the FAA for the operation of any of the affected aircraft. This final rule does allow APU usage during certain emergencies. We acknowledge that the costs associated with a terminating action, which would allow an operator to have use of its APU in flight, may be higher because the costs associated with retrofit of the airplane are likely to be higher than for implementing the change to the AFMS. This final rule only provides the costs associated with implementing the AFMS that restricts APU operations. There are no hardware or modification costs associated with this final rule. We do not agree with the commenter’s request to revise the estimated costs of compliance. The FAA uses a standard labor rate of $85 per hour for evaluation of all airworthiness actions, regardless of who performs the corrective action. The only cost associated with this final rule is for revising the AFM by inserting the applicable AFMS. Therefore, we have made no changes to this final rule regarding this issue. Additional Change Made to This Final Rule The FAA no longer considers this final rule to be an ‘‘interim action’’ and reference to ‘‘interim action,’’ which was included in the NPRM, has been omitted from this final rule. The FAA will accept the AFMS restrictions on APU operation as terminating action. If Gulfstream proposes design changes that would eliminate the APU firewall unsafe condition addressed by this AD, E:\FR\FM\02OCR1.SGM 02OCR1 45708 Federal Register / Vol. 82, No. 189 / Monday, October 2, 2017 / Rules and Regulations the FAA might consider further rulemaking. Conclusion We reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this AD with the changes described previously, and minor editorial changes. We have determined that these minor changes: • Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and • Do not add any additional burden upon the public than was already proposed in the NPRM. We also determined that these changes will not increase the economic burden on any operator or increase the scope of this AD. Related Service Information Under 1 CFR Part 51 We reviewed the following Gulfstream AFMSs. The AFMSs provide operating limitations on the use of the APU during certain ground and flight operations. These documents are distinct since they apply to different airplane models. • Gulfstream GIV/G300/G400 AFM Supplement GIV–2016–01, dated July 27, 2016, to the Gulfstream GIV AFM, dated April 22, 1987; the Gulfstream G300 AFM, dated January 15, 2003; and the Gulfstream G400 AFM, dated November 18, 2002. • Gulfstream G450/G350 AFM Supplement G450–2016–01, dated July 27, 2016, to the Gulfstream G450 AFM, dated August 12, 2004; and the Gulfstream G350 AFM, dated October 28, 2004. • Gulfstream GV AFM Supplement GV–2016–01, dated July 27, 2016, to the Gulfstream GV AFM, dated April 11, 1997. • Gulfstream G550/G500 AFM Supplement G550–2016–01, dated July 27, 2016, to the Gulfstream G550 AFM, dated August 14, 2003; and the Gulfstream G500 AFM, dated December 5, 2003. • Gulfstream GVI (G650) AFM Supplement G650–2016–01, dated July 27, 2016, to the Gulfstream GVI (G650) AFM, dated September 7, 2012. • Gulfstream GVI (G650ER) AFM Supplement G650ER–2016–03, dated July 27, 2016, to the Gulfstream GVI (G650ER) AFM, dated October 2, 2014. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section. Costs of Compliance We estimate that this AD affects 1,220 airplanes of U.S. registry. We estimate the following costs to comply with this AD: ESTIMATED COSTS Action Labor cost AFM revision ........................... 1 work-hour × $85 per hour = $85 ......................................... jstallworth on DSKBBY8HB2PROD with RULES 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. We are issuing 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. This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs VerDate Sep<11>2014 15:21 Sep 29, 2017 Jkt 244001 Cost per product Parts cost applicable to transport category airplanes to the Director of the System Oversight Division. Regulatory Findings We have determined that this AD will not have federalism implications under Executive Order 13132. This AD will 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 that this AD: (1) Is not a ‘‘significant regulatory action’’ under Executive Order 12866, (2) Is not a ‘‘significant rule’’ under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), (3) Will not affect intrastate aviation in Alaska, and (4) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. $0 Cost on U.S. operators $85 $103,700 Adoption of the Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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 removing Airworthiness Directive (AD) 2009–17–01, Amendment 39–15991 (74 FR 40061, August 11, 2009), and adding the following new AD: ■ 2017–20–08 Gulfstream Aerospace Corporation: Amendment 39–19065; Docket No. FAA–2016–9522; Product Identifier 2016–NM–144–AD. (a) Effective Date This AD is effective November 6, 2017. List of Subjects in 14 CFR Part 39 (b) Affected ADs This AD replaces AD 2009–17–01, Amendment 39–15991 (74 FR 40061, August 11, 2009) (‘‘AD 2009–17–01’’). Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. (c) Applicability This AD applies to the Gulfstream Aerospace Corporation airplanes, certificated PO 00000 Frm 00030 Fmt 4700 Sfmt 4700 E:\FR\FM\02OCR1.SGM 02OCR1 Federal Register / Vol. 82, No. 189 / Monday, October 2, 2017 / Rules and Regulations in any category, identified in paragraphs (c)(1) through (c)(5) of this AD. (1) Model G–IV airplanes, having serial numbers (S/Ns) 1000 and subsequent. (2) Model GIV–X airplanes, having S/Ns 4001 and subsequent. (3) Model GV airplanes, having S/Ns 501 and subsequent. (4) Model GV–SP airplanes, having S/Ns 5001 and subsequent. (5) Model GVI airplanes, having S/Ns 6001 and subsequent. (d) Subject Air Transport Association (ATA) of America Code 49, Airborne Auxiliary Power; and 53, Fuselage. (e) Unsafe Condition This AD was prompted by a report indicating that the type design sealant (Aerospace Material Specification (AMS) 3374), as applied to the auxiliary power unit (APU) enclosure (firewall), does not meet the requirement in 14 CFR 25.1191(b)(1) for a firewall to be fireproof, and failed a certification test and a company test. We are issuing this AD to provide the flight crew with operating procedures for airplanes that have AMS 3374 or Gulfstream Material Specification (GMS) 4107 sealant applied to the APU enclosure. Under certain anomalous conditions such as an APU failure/APU compartment fire, AMS 3374 or GMS 4107 sealant could ignite the exterior surfaces of the APU enclosure and result in propagation of an uncontained fire to other critical areas of the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. jstallworth on DSKBBY8HB2PROD with RULES (g) Airplane Flight Manual (AFM) Revision Within 30 days after the effective date of this AD, revise the Limitations Section of the applicable Gulfstream AFM specified in paragraphs (h)(1) through (h)(6) of this AD to include the information in the applicable Gulfstream AFM supplement (AFMS) specified in paragraphs (h)(1) through (h)(6) of this AD. These AFMSs introduce operating limitations on the use of the APU during certain ground and flight operations. This AFM revision may be done by inserting a copy of the applicable AFMS into the applicable AFM specified in paragraphs (h)(1) through (h)(6) of this AD. When the AFMS has been included in the general revision of the AFM, the general revision may be inserted into the AFM, provided the relevant information in the general revision is identical to that in the applicable AFMS specified in paragraphs (h)(1) through (h)(6) of this AD. (h) AFMSs For the AFM revision required by paragraph (g) of this AD, insert the applicable AFMS into the applicable Gulfstream AFM identified in paragraphs (h)(1) through (h)(6) of this AD. (1) Gulfstream GIV/G300/G400 AFM Supplement GIV–2016–01, dated July 27, 2016, to the Gulfstream GIV AFM, dated April 22, 1987; the Gulfstream G300 AFM, VerDate Sep<11>2014 15:21 Sep 29, 2017 Jkt 244001 dated January 15, 2003; and the Gulfstream G400 AFM, dated November 18, 2002. (2) Gulfstream G450/G350 AFM Supplement G450–2016–01, dated July 27, 2016, to the Gulfstream G450 AFM, dated August 12, 2004; and the Gulfstream G350 AFM, dated October 28, 2004. (3) Gulfstream GV AFM Supplement GV– 2016–01, dated July 27, 2016, to the Gulfstream GV AFM, dated April 11, 1997. (4) Gulfstream G550/G500 AFM Supplement G550–2016–01, dated July 27, 2016, to the Gulfstream G550 AFM, dated August 14, 2003; and the Gulfstream G500 AFM, dated December 5, 2003. (5) Gulfstream GVI (G650) AFM Supplement G650–2016–01, dated July 27, 2016, to the Gulfstream GVI (G650) AFM, dated September 7, 2012. (6) Gulfstream GVI (G650ER) AFM Supplement G650ER–2016–03, dated July 27, 2016, to the Gulfstream GVI (G650ER) AFM, dated October 2, 2014. (i) Credit for Previous Actions This paragraph provides credit for the action required by paragraph (g) of this AD, if that action was performed before the effective date of this AD using the applicable service information specified in paragraphs (i)(1) through (i)(4) of this AD. This service information was incorporated by reference in AD 2009–17–01. (1) Gulfstream G–IV/G300/G400 AFM Supplement G–IV–2009–02, Revision 1, dated June 25, 2009, to the Gulfstream GIV AFM, the Gulfstream G300 AFM, and the Gulfstream G400 AFM. (2) Gulfstream G450/G350 AFM Supplement G450–2009–03, Revision 1, dated June 25, 2009, to the Gulfstream G450 AFM and the Gulfstream G350 AFM. (3) Gulfstream GV AFM Supplement GV– 2009–03, Revision 1, dated June 25, 2009, to the Gulfstream GV AFM. (4) Gulfstream G550/G500 AFM Supplement G550–2009–03, Revision 1, dated June 25, 2009, Gulfstream G550 AFM and the Gulfstream G500 AFM. (j) 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 paragraph (k)(1) of this AD. (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. (3) AMOCs approved previously for paragraph (h) of AD 2009–17–01 are approved as AMOCs for the corresponding provisions of paragraph (g) of this AD. (k) Related Information (1) For more information about this AD, contact Ky Phan, Aerospace Engineer, Propulsion and Services Section, FAA, PO 00000 Frm 00031 Fmt 4700 Sfmt 4700 45709 Atlanta ACO Branch, 1701 Columbia Avenue, College Park, GA 30337; phone: 404–474–5536; fax: 404–474–5606; email: ky.phan@faa.gov. (2) Service information identified in this AD that is not incorporated by reference is available at the addresses specified in paragraphs (l)(3) and (l)(4) of this AD. (l) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this service information as applicable to do the actions required by this AD, unless the AD specifies otherwise. (i) Gulfstream GIV/G300/G400 Airplane Flight Manual (AFM) Supplement GIV– 2016–01, dated July 27, 2016, to the Gulfstream GIV AFM, dated April 22, 1987; the Gulfstream G300 AFM, dated January 15, 2003; and the Gulfstream G400 AFM, dated November 18, 2002. (ii) Gulfstream G450/G350 Airplane Flight Manual (AFM) Supplement G450–2016–01, dated July 27, 2016, to the Gulfstream G450 AFM, dated August 12, 2004; and the Gulfstream G350 AFM, dated October 28, 2004. (iii) Gulfstream GV Airplane Flight Manual (AFM) Supplement GV–2016–01, dated July 27, 2016, to the Gulfstream GV AFM, dated April 11, 1997. (iv) Gulfstream G550/G500 Airplane Flight Manual (AFM) Supplement G550–2016–01, dated July 27, 2016, to the Gulfstream G550 AFM, dated August 14, 2003; and the Gulfstream G500 AFM, dated December 5, 2003. (v) Gulfstream GVI (G650) Airplane Flight Manual (AFM) Supplement G650–2016–01, dated July 27, 2016, to the Gulfstream GVI (G650) AFM, dated September 7, 2012. (vi) Gulfstream GVI (G650ER) Airplane Flight Manual (AFM) Supplement G650ER– 2016–03, dated July 27, 2016, to the Gulfstream GVI (G650ER) AFM, dated October 2, 2014. (3) For service information identified in this AD, contact Gulfstream Aerospace Corporation, Technical Publications Dept., P.O. Box 2206, Savannah, GA 31402–2206; telephone 800–810–4853; fax 912–965–3520; email pubs@gulfstream.com; Internet https:// www.gulfstream.com/product_support/ technical_pubs/pubs/index.htm. (4) You may view this service information at the FAA, Transport Standards Branch, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425–227–1221. (5) You may view this service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202–741–6030, or go to: https:// www.archives.gov/federal-register/cfr/ibrlocations.html. E:\FR\FM\02OCR1.SGM 02OCR1 45710 Federal Register / Vol. 82, No. 189 / Monday, October 2, 2017 / Rules and Regulations Issued in Renton, Washington, on September 18, 2017. Dionne Palermo, Acting Director, System Oversight Division, Aircraft Certification Service. for and locating Docket No. FAA–2017– 0099. Examining the AD Docket [FR Doc. 2017–20831 Filed 9–29–17; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2017–0099; Product Identifier 2017–NE–02–AD; Amendment 39– 19035; AD 2017–19–05] RIN 2120–AA64 Airworthiness Directives; Siemens S.A.S. Smoke Detectors Republication Editorial Note: Rule document 2017– 20425 was originally published on pages 44717 through 44720 in the issue of Tuesday, September 26, 2017. In that publication, on page 44719, in Figure 1, a number was omitted from the first entry under column ‘‘P/N’’. Also in that publication, on page 44720, in Figure 3, a number was omitted from the table heading. The corrected document is published here in its entirety. Federal Aviation Administration (FAA), DOT. ACTION: Final rule. AGENCY: We are adopting a new airworthiness directive (AD) for certain Siemens S.A.S. smoke detectors installed on various transport category airplanes. This AD requires inspection and replacement of the affected smoke detectors. This AD was prompted by a report that the affected smoke detectors failed an acceptance test. We are issuing this AD to correct the unsafe condition on these products. DATES: This AD becomes effective October 31, 2017. The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of October 31, 2017. ADDRESSES: For service information identified in this final rule, contact Siemens, Aviation Customer Support, 697 Rue Fourny, 78530 Buc, France; phone: (33) 1 3084 6650; fax: (33) 1 3956 1364. You may view this service information at the FAA, Engine and Propeller Standards Branch, Policy and Innovation Division, 1200 District Avenue, Burlington, MA. For information on the availability of this material at the FAA, call 781- 238–7125. It is also available on the Internet at https://www.regulations.gov by searching jstallworth on DSKBBY8HB2PROD with RULES 15:21 Sep 29, 2017 Erin Hulverson, Aerospace Engineer, FAA, Boston ACO Branch, Compliance and Airworthiness Division, 1200 District Avenue, Burlington, MA 01803; phone: 781–238–7655; fax: 781–238–7199; email: erin.hulverson@faa.gov. FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: Discussion SUMMARY: VerDate Sep<11>2014 You may examine the AD docket on the Internet at https:// www.regulations.gov by searching for and locating Docket No. FAA–2017– 0099; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the mandatory continuing airworthiness information (MCAI), the regulatory evaluation, any comments received, and other information. The address for the Docket Office (phone: 800–647–5527) is Document Management Facility, U.S. Department of Transportation, Docket Operations, M–30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590. Jkt 244001 We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to the specified products. The NPRM was published in the Federal Register on April 20, 2017 (82 FR 18588). The NPRM proposed to correct an unsafe condition for the specified products. The MCAI states: During a maintenance operation, some smoke detectors P/N PMC1102–02 failed an acceptance test, due to a significant degraded optical sensitivity. Investigation results concluded that light-emitting diodes (LED) were abnormally degraded, affecting specific batches where changes occurred in the LED manufacturer production process. Further investigation has determined that the affected LED have been installed on smoke detectors manufactured between November 2010 and January 2013, and on certain repaired units. This condition, if not corrected, will generate an abnormal ageing of the smoke detector, leading to a decrease of the light intensity capability, possibly resulting in failure to detect smoke and consequent risk of an on-board uncontrolled fire. You may obtain further information by examining the MCAI in the AD docket on the Internet at https:// www.regulations.gov by searching for and locating Docket No. FAA–2017– 0099. PO 00000 Frm 00032 Fmt 4700 Sfmt 4700 Comments We gave the public the opportunity to participate in developing this AD. We considered the comments received. Comment on Certifying Authority The European Aviation Safety Agency (EASA) commented that the affected smoke detectors were approved by EASA rather than by France. We agree. These smoke detectors were approved by EASA. We did not change this AD because this AD does not reference the certifying authority for these smoke detectors. The section commented on by EASA exists only in the ‘‘Determination and Requirements of This Proposed AD’’ section of the NPRM. We did not change this AD. Request To Revise Applicability Delta Air Lines (Delta) requested that we revise the Applicability section of this AD to remove the reference to the date range when certain affected smoke detectors were produced. Delta indicated that the NPRM may be interpreted as implying that there are more affected smoke detector serial numbers than those identified in paragraph 1/D/ of Siemens Service Information Letter (SIL) PMC–26–002, Revision No. 1, dated January 2016, and of SIL PMC–26–003, Revision No. 2, dated February, 2016. Delta commented that removing the date range from the Applicability section of this AD would clarify applicability for operators. We agree. We find that providing the part numbers (P/Ns) and serial numbers (S/Ns) for the affected smoke detectors sufficiently identifies all affected detectors. We revised this AD by removing the reference to the production date range from the Applicability section of this AD. Request To Revise Compliance Schedule Delta requested that we revise paragraph (f)(2) in the compliance section of this AD to indicate that repaired units identified in Figure (1) to paragraph (c) of this AD should be replaced within 5 months after the effective date of this AD. Delta commented that the NPRM does not specify when these affected detectors are to be replaced. We agree. We revised the compliance section of this AD to specify that smoke detectors identified in paragraph (c)(2) of this AD must be replaced within 5 months after the effective date of this AD. Support for This AD The Air Line Pilots Association, International, commented that it E:\FR\FM\02OCR1.SGM 02OCR1

Agencies

[Federal Register Volume 82, Number 189 (Monday, October 2, 2017)]
[Rules and Regulations]
[Pages 45705-45710]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-20831]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-9522; Product Identifier 2016-NM-144-AD; Amendment 
39-19065; AD 2017-20-08]
RIN 2120-AA64


Airworthiness Directives; Gulfstream Aerospace Corporation 
Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: We are superseding Airworthiness Directive (AD) 2009-17-01, 
which applied to certain Gulfstream Model G-IV, GIV-X, GV-SP airplanes 
and Model GV airplanes. AD 2009-17-01 required an inspection for 
sealant applied to the exterior of the auxiliary power unit (APU) 
enclosure (firewall), and a revision of the airplane flight manual 
(AFM), as applicable. This AD requires revising the AFM and revising 
the applicability to include additional airplanes. This AD was prompted 
by a report indicating that the type design sealant applied to the APU 
enclosure failed certain tests. We are issuing this AD to address the 
unsafe condition on these products.

DATES: This AD is effective November 6, 2017.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of November 6, 
2017.

ADDRESSES: For service information identified in this final rule, 
contact Gulfstream Aerospace Corporation, Technical Publications Dept., 
P.O. Box 2206, Savannah, GA 31402-2206; telephone 800-810-4853; fax 
912-965-3520; email pubs@gulfstream.com; Internet https://
www.gulfstream.com/

[[Page 45706]]

product_support/technical_pubs/pubs/index.htm. You may view this 
referenced service information at the FAA, Transport Standards Branch, 
1601 Lind Avenue SW., Renton, WA. For information on the availability 
of this material at the FAA, call 425-227-1221. It is also available on 
the Internet at https://www.regulations.gov by searching for and 
locating Docket No. FAA-2016-9522.

Examining the AD Docket

    You may examine the AD docket on the Internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2016-
9522; or in person at the Docket Management Facility between 9 a.m. and 
5 p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this AD, the regulatory evaluation, any comments received, and 
other information. The address for the Docket Office (phone: 800-647-
5527) is Docket Management Facility, U.S. Department of Transportation, 
Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 
New Jersey Avenue SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Ky Phan, Aerospace Engineer, 
Propulsion and Services Section, FAA, Atlanta ACO Branch, 1701 Columbia 
Avenue, College Park, GA 30337; phone: 404-474-5536; fax: 404-474-5606; 
email: ky.phan@faa.gov.

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to supersede AD 2009-17-01, Amendment 39-15991 (74 FR 40061, 
August 11, 2009) (``AD 2009-17-01''). AD 2009-17-01 applied to certain 
Gulfstream Model G-IV, GIV-X, GV-SP airplanes, and Model GV airplanes. 
The NPRM published in the Federal Register on January 4, 2017 (82 FR 
737) (``the NPRM''). The NPRM was prompted by a report indicating that 
the type design sealant (Aerospace Material Specification (AMS) 3374), 
applied to the APU enclosure, does not meet the requirement in 14 CFR 
25.1191(b)(1) for a firewall to be fireproof, and failed a 
certification test and a company test. The NPRM proposed to require 
revising the AFM and revising the applicability to include additional 
airplanes. We are issuing this AD to provide the flight crew with 
operating procedures for airplanes that have AMS 3374 or Gulfstream 
Material Specification (GMS) 4107 sealant applied to the APU enclosure 
(firewall). Under certain anomalous conditions such as an APU failure/
APU compartment fire, AMS 3374 or GMS 4107 sealant could ignite the 
exterior surfaces of the APU enclosure, and result in propagation of an 
uncontained fire to other critical areas of the airplane.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the NPRM and 
the FAA's response to each comment.

Request To Withdraw the NPRM

    Gulfstream requested that the NPRM be withdrawn. The commenter 
stated that the FAA's findings and decisions in the proposed AD are not 
based on analysis of the commenter's supporting data and accepted risk 
and safety assessment methodologies. The commenter asserted that its 
risk assessments, performed using the FAA's Transport Airplane Risk 
Assessment Methodology (TARAM) Handbook, are within the allowable 
guidelines of the FAA's TARAM Handbook.
    We do not agree with the commenter's request because this final 
rule is consistent with FAA policy and orders. The FAA's TARAM is used 
to assess risk associated with a wide variety of potential safety 
issues. The FAA typically follows the defined risk guidelines contained 
in the TARAM Handbook for transport category airplanes. However, 
occasionally, other factors affect the decision on whether to issue an 
AD. FAA Order 8110.107A, ``Monitor Safety/Analyze Data,'' paragraph 2-
10.e. states:

    In rare situations the Aviation Safety Engineer or FAA 
management may, based on factors unrelated to the risk analysis, 
make recommendations not consistent with risk guidelines for ADs or 
other mandatory corrective actions. The decision to accept or reject 
these recommendations is made during the CARB [Corrective Action 
Review Board].

    One such factor, unrelated to risk analysis, is whether the 
affected system provides an emergency or safety function. Examples of 
emergency/safety systems include seatbelts, life rafts, oxygen systems, 
and firewalls. Failure of emergency systems typically do not cause an 
accident, but can greatly increase the probability of fatalities in the 
event of an additional unrelated failure. TARAM analyses of emergency/
safety systems typically indicate a low TARAM risk. This is due to the 
fact that the precipitating event is very rare, for example, high-g 
decelerations due to an accident, ditching, explosive decompression, 
and engine fire. Ultimately, the decision regarding whether to mandate 
airworthiness action for a condition is the responsibility of the FAA's 
CARB, which for this AD was comprised of representatives from the 
Atlanta ACO Branch, Transport Airplane Directorate, Atlanta MIDO 
Section, and the Aircraft Evaluation Group. The CARB unanimously 
concluded that factors other than the TARAM risk indicated the need to 
mandate corrective action for Gulfstream APU firewalls assembled using 
AMS 3374 sealant, in addition to the previously mandated requirements 
for Gulfstream APU firewalls assembled using GMS 4107 sealant.
    Several 14 CFR part 25 regulations are intended to prevent the 
spread of a fire to other critical areas of an airplane in the event of 
an in-flight or ground fire; one of these regulations is 14 CFR 25.1191 
(``Firewalls''). The 14 CFR part 25 regulations include requirements 
for (1) fire detection, (2) fire suppression, and (3) fire containment 
by a firewall. The AMS 3374 sealant, as applied to the Gulfstream APU 
firewall type designs that are the subject of this AD, has been shown 
by fire testing to result in backside (cold side) ignition of the 
firewall when exposed to a 2,000 degree Fahrenheit flame for 15 
minutes, thus violating the 14 CFR part 25 requirement for the firewall 
to be fireproof (refer to FAA Advisory Circular (AC) 20-135, 
``Powerplant Installation and Propulsion System Component Fire 
Protection Test Methods, Standards and Criteria,'' dated February 6, 
1990 (``AC 20-135''), for firewall fire testing guidance.) Previous 
fire testing also confirmed that Gulfstream APU firewalls assembled 
with GMS 4107 exhibited backside ignition during those tests. The 
backside ignition of the Gulfstream APU firewalls occurred in an area 
of the airplane that does not have fire detection or fire suppression. 
This is a non-compliance with the requirements of 14 CFR 25.1191(b)(1) 
for firewalls to be fireproof. If an APU fire occurred in flight or on 
the ground on such a non-compliant airplane, it could result in 
backside ignition of the firewall, potentially resulting in propagation 
of an uncontained fire to other critical areas of the airplane. The 
area outside and adjacent to the Gulfstream APU firewall contains many 
airplane critical systems such as empennage structure, flight control 
components, fuel lines, and oil lines. The FAA finds that APU 
operations on the affected Gulfstream models without a firewall that is 
fireproof, as required by 14 CFR 25.1191, constitutes an unsafe 
condition. The FAA performed an

[[Page 45707]]

additional TARAM analysis, which indicated a higher risk than the 
results of the original Gulfstream TARAM analysis. However, we want to 
point out that neither TARAM analysis was the sole consideration for 
mandating corrective action. We have made no changes to this AD in this 
regard.

Request for Separate AD Action for AMS 3374 Sealant

    Gulfstream requested that the FAA issue a separate rulemaking 
action to address the use of AMS 3374 sealant. The commenter deems it 
inaccurate to associate the GMS 4107 sealant unsafe condition with the 
application of the AMS 3374 sealant. Gulfstream also considers the 
corrective actions to be significantly different for the two types of 
sealants.
    We disagree with the commenter's request. Many of the Gulfstream 
airplanes affected by this AD have both GMS 4107 and AMS 3374 sealants 
used in the fabrication of APU firewalls. The use of GMS 4107 and/or 
AMS 3374 sealants, per the Gulfstream type design for the APU firewalls 
that are the subject of this AD action, has resulted in backside 
ignition of the APU firewall in fire tests that were intended to 
demonstrate that the firewalls are fireproof. The corrective action for 
both types of sealants is identical, applying restrictions on APU 
operations. The corrective actions specified in the AD being 
superseded, AD 2009-17-01, did not address APU firewalls fabricated 
using AMS 3374 sealant. Subsequent fire testing has shown that AMS 3374 
sealant, used as specified in the Gulfstream type design, does not 
comply with the regulations that require a firewall to be fireproof; 
therefore, AD 2009-17-01 must be superseded to include APU firewalls 
fabricated using AMS 3374 sealant. Future rulemaking to incorporate a 
solution proposed by Gulfstream might be considered when and if a 
proposed solution is made available to the FAA. We have made no changes 
to this AD in this regard.

Request To Clarify Terminology

    Gulfstream requested that the FAA revise the NPRM by removing all 
of the statements that AMS 3374 sealant is flammable. The commenter 
stated that it is not accurate to make a general statement that AMS 
3374 sealant is flammable because there are many applications where AMS 
3374 sealants are compliant with applicable fireproof certification 
requirements.
    We partially agree with the commenter's request. The FAA's 
certification requirement is that firewalls be fireproof, not that the 
sealant be fireproof. The FAA does not have specific requirements for 
sealant, apart from the requirement that its use in the assembly of 
firewalls must result in a fireproof firewall assembly.
    Also, the commenter's statement that there are many applications 
where AMS 3374 sealants are compliant with applicable fireproof 
certification requirements may be partially correct. There could be 
firewalls assembled using AMS 3374 sealants that do meet the applicable 
fireproof certification requirements. The issue addressed by this final 
rule is that Gulfstream's application of AMS 3374 sealant to the APU 
firewall assemblies affected by this rulemaking action is not compliant 
with the airworthiness requirement for the firewall to be fireproof. 
The AMS 3374 sealant does meet the requirements of an industry 
specification, the Society of Automotive Engineers (SAE) Standard AMS 
3374. Compliance with an SAE standard is not equivalent to, and does 
not satisfy, compliance with the FAA certification requirement that 
firewalls be fireproof. AC 20-135 is used throughout the aviation 
industry as guidance material for how to show compliance with the FAA's 
requirement that firewalls be fireproof. Regarding the use of sealants, 
AC 20-135 provides the following guidance:

    Outgassing. A characteristic of bonded construction firewall 
materials and seal materials is the outgassing of the volatile 
constituents of the bonding resins or seal materials. This can occur 
from either the hot or cool side surface of the specimens during the 
test. These gasses are, in most instances, highly flammable. 
Ignition occurring on the cool side is unacceptable in passing the 
fire test. . . . For these types of construction, no ``cool side'' 
ignition is allowed and verification is required.

There are many variables that determine if a given firewall 
configuration meets the airworthiness requirement to be fireproof. 
Sealants are known to outgas volatile constituents. In the case of the 
Gulfstream APU firewall type design, outgassed constituents of AMS 3374 
sealant ignited on the backside during fire testing, and therefore, the 
firewall does not meet the definition of fireproof per AC 20-135. We 
have changed the wording in this final rule to specify that the type 
design sealant (AMS 3374), as applied in the Gulfstream APU firewall, 
does not meet the airworthiness requirement in 14 CFR 25.1191(b)(1), 
for a firewall to be fireproof.
    We do not agree that AMS 3374 sealant is compliant with applicable 
fireproof certification requirements because the FAA does not 
certificate sealants; the FAA certificates that firewalls are 
fireproof. Therefore, we have made no changes to this AD in this 
regard.

Request To Revise the Estimated Costs of Compliance

    Gulfstream requested that the estimated costs of compliance in the 
NPRM be revised to include costs associated with an operator's 
inability to use the APU during normal operations, and the cost 
associated with a terminating action. The commenter noted that the 
estimated costs in the NPRM are associated with physically revising the 
AFM by inserting the applicable AFM supplement (AFMS). The commenter 
stated that the costs associated with a terminating action that would 
allow an operator to use its APU in flight is much more expensive, and 
depending on the number of airplanes that need to be retrofitted, the 
costs are likely to be tens of millions of dollars.
    The FAA did not include any costs associated with an operator's 
inability to use the APU during normal operations because APU usage is 
not required by the FAA for the operation of any of the affected 
aircraft. This final rule does allow APU usage during certain 
emergencies.
    We acknowledge that the costs associated with a terminating action, 
which would allow an operator to have use of its APU in flight, may be 
higher because the costs associated with retrofit of the airplane are 
likely to be higher than for implementing the change to the AFMS. This 
final rule only provides the costs associated with implementing the 
AFMS that restricts APU operations. There are no hardware or 
modification costs associated with this final rule.
    We do not agree with the commenter's request to revise the 
estimated costs of compliance. The FAA uses a standard labor rate of 
$85 per hour for evaluation of all airworthiness actions, regardless of 
who performs the corrective action. The only cost associated with this 
final rule is for revising the AFM by inserting the applicable AFMS. 
Therefore, we have made no changes to this final rule regarding this 
issue.

Additional Change Made to This Final Rule

    The FAA no longer considers this final rule to be an ``interim 
action'' and reference to ``interim action,'' which was included in the 
NPRM, has been omitted from this final rule. The FAA will accept the 
AFMS restrictions on APU operation as terminating action. If Gulfstream 
proposes design changes that would eliminate the APU firewall unsafe 
condition addressed by this AD,

[[Page 45708]]

the FAA might consider further rulemaking.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
this AD with the changes described previously, and minor editorial 
changes. We have determined that these minor changes:
     Are consistent with the intent that was proposed in the 
NPRM for correcting the unsafe condition; and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM.
    We also determined that these changes will not increase the 
economic burden on any operator or increase the scope of this AD.

Related Service Information Under 1 CFR Part 51

    We reviewed the following Gulfstream AFMSs. The AFMSs provide 
operating limitations on the use of the APU during certain ground and 
flight operations. These documents are distinct since they apply to 
different airplane models.
     Gulfstream GIV/G300/G400 AFM Supplement GIV-2016-01, dated 
July 27, 2016, to the Gulfstream GIV AFM, dated April 22, 1987; the 
Gulfstream G300 AFM, dated January 15, 2003; and the Gulfstream G400 
AFM, dated November 18, 2002.
     Gulfstream G450/G350 AFM Supplement G450-2016-01, dated 
July 27, 2016, to the Gulfstream G450 AFM, dated August 12, 2004; and 
the Gulfstream G350 AFM, dated October 28, 2004.
     Gulfstream GV AFM Supplement GV-2016-01, dated July 27, 
2016, to the Gulfstream GV AFM, dated April 11, 1997.
     Gulfstream G550/G500 AFM Supplement G550-2016-01, dated 
July 27, 2016, to the Gulfstream G550 AFM, dated August 14, 2003; and 
the Gulfstream G500 AFM, dated December 5, 2003.
     Gulfstream GVI (G650) AFM Supplement G650-2016-01, dated 
July 27, 2016, to the Gulfstream GVI (G650) AFM, dated September 7, 
2012.
     Gulfstream GVI (G650ER) AFM Supplement G650ER-2016-03, 
dated July 27, 2016, to the Gulfstream GVI (G650ER) AFM, dated October 
2, 2014.
    This service information is reasonably available because the 
interested parties have access to it through their normal course of 
business or by the means identified in the ADDRESSES section.

Costs of Compliance

    We estimate that this AD affects 1,220 airplanes of U.S. registry. 
We estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
               Action                         Labor cost            Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
AFM revision.......................  1 work-hour x $85 per hour               $0             $85        $103,700
                                      = $85.
----------------------------------------------------------------------------------------------------------------

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.
    We are issuing 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.
    This AD is issued in accordance with authority delegated by the 
Executive Director, Aircraft Certification Service, as authorized by 
FAA Order 8000.51C. In accordance with that order, issuance of ADs is 
normally a function of the Compliance and Airworthiness Division, but 
during this transition period, the Executive Director has delegated the 
authority to issue ADs applicable to transport category airplanes to 
the Director of the System Oversight Division.

Regulatory Findings

    We have determined that this AD will not have federalism 
implications under Executive Order 13132. This AD will 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 that this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) Will 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.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 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 removing Airworthiness Directive (AD) 
2009-17-01, Amendment 39-15991 (74 FR 40061, August 11, 2009), and 
adding the following new AD:

2017-20-08 Gulfstream Aerospace Corporation: Amendment 39-19065; 
Docket No. FAA-2016-9522; Product Identifier 2016-NM-144-AD.

(a) Effective Date

    This AD is effective November 6, 2017.

(b) Affected ADs

    This AD replaces AD 2009-17-01, Amendment 39-15991 (74 FR 40061, 
August 11, 2009) (``AD 2009-17-01'').

(c) Applicability

    This AD applies to the Gulfstream Aerospace Corporation 
airplanes, certificated

[[Page 45709]]

in any category, identified in paragraphs (c)(1) through (c)(5) of 
this AD.
    (1) Model G-IV airplanes, having serial numbers (S/Ns) 1000 and 
subsequent.
    (2) Model GIV-X airplanes, having S/Ns 4001 and subsequent.
    (3) Model GV airplanes, having S/Ns 501 and subsequent.
    (4) Model GV-SP airplanes, having S/Ns 5001 and subsequent.
    (5) Model GVI airplanes, having S/Ns 6001 and subsequent.

(d) Subject

    Air Transport Association (ATA) of America Code 49, Airborne 
Auxiliary Power; and 53, Fuselage.

(e) Unsafe Condition

    This AD was prompted by a report indicating that the type design 
sealant (Aerospace Material Specification (AMS) 3374), as applied to 
the auxiliary power unit (APU) enclosure (firewall), does not meet 
the requirement in 14 CFR 25.1191(b)(1) for a firewall to be 
fireproof, and failed a certification test and a company test. We 
are issuing this AD to provide the flight crew with operating 
procedures for airplanes that have AMS 3374 or Gulfstream Material 
Specification (GMS) 4107 sealant applied to the APU enclosure. Under 
certain anomalous conditions such as an APU failure/APU compartment 
fire, AMS 3374 or GMS 4107 sealant could ignite the exterior 
surfaces of the APU enclosure and result in propagation of an 
uncontained fire to other critical areas of the airplane.

(f) Compliance

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

(g) Airplane Flight Manual (AFM) Revision

    Within 30 days after the effective date of this AD, revise the 
Limitations Section of the applicable Gulfstream AFM specified in 
paragraphs (h)(1) through (h)(6) of this AD to include the 
information in the applicable Gulfstream AFM supplement (AFMS) 
specified in paragraphs (h)(1) through (h)(6) of this AD. These 
AFMSs introduce operating limitations on the use of the APU during 
certain ground and flight operations. This AFM revision may be done 
by inserting a copy of the applicable AFMS into the applicable AFM 
specified in paragraphs (h)(1) through (h)(6) of this AD. When the 
AFMS has been included in the general revision of the AFM, the 
general revision may be inserted into the AFM, provided the relevant 
information in the general revision is identical to that in the 
applicable AFMS specified in paragraphs (h)(1) through (h)(6) of 
this AD.

(h) AFMSs

    For the AFM revision required by paragraph (g) of this AD, 
insert the applicable AFMS into the applicable Gulfstream AFM 
identified in paragraphs (h)(1) through (h)(6) of this AD.
    (1) Gulfstream GIV/G300/G400 AFM Supplement GIV-2016-01, dated 
July 27, 2016, to the Gulfstream GIV AFM, dated April 22, 1987; the 
Gulfstream G300 AFM, dated January 15, 2003; and the Gulfstream G400 
AFM, dated November 18, 2002.
    (2) Gulfstream G450/G350 AFM Supplement G450-2016-01, dated July 
27, 2016, to the Gulfstream G450 AFM, dated August 12, 2004; and the 
Gulfstream G350 AFM, dated October 28, 2004.
    (3) Gulfstream GV AFM Supplement GV-2016-01, dated July 27, 
2016, to the Gulfstream GV AFM, dated April 11, 1997.
    (4) Gulfstream G550/G500 AFM Supplement G550-2016-01, dated July 
27, 2016, to the Gulfstream G550 AFM, dated August 14, 2003; and the 
Gulfstream G500 AFM, dated December 5, 2003.
    (5) Gulfstream GVI (G650) AFM Supplement G650-2016-01, dated 
July 27, 2016, to the Gulfstream GVI (G650) AFM, dated September 7, 
2012.
    (6) Gulfstream GVI (G650ER) AFM Supplement G650ER-2016-03, dated 
July 27, 2016, to the Gulfstream GVI (G650ER) AFM, dated October 2, 
2014.

(i) Credit for Previous Actions

    This paragraph provides credit for the action required by 
paragraph (g) of this AD, if that action was performed before the 
effective date of this AD using the applicable service information 
specified in paragraphs (i)(1) through (i)(4) of this AD. This 
service information was incorporated by reference in AD 2009-17-01.
    (1) Gulfstream G-IV/G300/G400 AFM Supplement G-IV-2009-02, 
Revision 1, dated June 25, 2009, to the Gulfstream GIV AFM, the 
Gulfstream G300 AFM, and the Gulfstream G400 AFM.
    (2) Gulfstream G450/G350 AFM Supplement G450-2009-03, Revision 
1, dated June 25, 2009, to the Gulfstream G450 AFM and the 
Gulfstream G350 AFM.
    (3) Gulfstream GV AFM Supplement GV-2009-03, Revision 1, dated 
June 25, 2009, to the Gulfstream GV AFM.
    (4) Gulfstream G550/G500 AFM Supplement G550-2009-03, Revision 
1, dated June 25, 2009, Gulfstream G550 AFM and the Gulfstream G500 
AFM.

(j) 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 paragraph (k)(1) of this AD.
    (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.
    (3) AMOCs approved previously for paragraph (h) of AD 2009-17-01 
are approved as AMOCs for the corresponding provisions of paragraph 
(g) of this AD.

(k) Related Information

    (1) For more information about this AD, contact Ky Phan, 
Aerospace Engineer, Propulsion and Services Section, FAA, Atlanta 
ACO Branch, 1701 Columbia Avenue, College Park, GA 30337; phone: 
404-474-5536; fax: 404-474-5606; email: ky.phan@faa.gov.
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (l)(3) and (l)(4) of this AD.

(l) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Gulfstream GIV/G300/G400 Airplane Flight Manual (AFM) 
Supplement GIV-2016-01, dated July 27, 2016, to the Gulfstream GIV 
AFM, dated April 22, 1987; the Gulfstream G300 AFM, dated January 
15, 2003; and the Gulfstream G400 AFM, dated November 18, 2002.
    (ii) Gulfstream G450/G350 Airplane Flight Manual (AFM) 
Supplement G450-2016-01, dated July 27, 2016, to the Gulfstream G450 
AFM, dated August 12, 2004; and the Gulfstream G350 AFM, dated 
October 28, 2004.
    (iii) Gulfstream GV Airplane Flight Manual (AFM) Supplement GV-
2016-01, dated July 27, 2016, to the Gulfstream GV AFM, dated April 
11, 1997.
    (iv) Gulfstream G550/G500 Airplane Flight Manual (AFM) 
Supplement G550-2016-01, dated July 27, 2016, to the Gulfstream G550 
AFM, dated August 14, 2003; and the Gulfstream G500 AFM, dated 
December 5, 2003.
    (v) Gulfstream GVI (G650) Airplane Flight Manual (AFM) 
Supplement G650-2016-01, dated July 27, 2016, to the Gulfstream GVI 
(G650) AFM, dated September 7, 2012.
    (vi) Gulfstream GVI (G650ER) Airplane Flight Manual (AFM) 
Supplement G650ER-2016-03, dated July 27, 2016, to the Gulfstream 
GVI (G650ER) AFM, dated October 2, 2014.
    (3) For service information identified in this AD, contact 
Gulfstream Aerospace Corporation, Technical Publications Dept., P.O. 
Box 2206, Savannah, GA 31402-2206; telephone 800-810-4853; fax 912-
965-3520; email pubs@gulfstream.com; Internet https://www.gulfstream.com/product_support/technical_pubs/pubs/index.htm.
    (4) You may view this service information at the FAA, Transport 
Standards Branch, 1601 Lind Avenue SW., Renton, WA. For information 
on the availability of this material at the FAA, call 425-227-1221.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, call 202-741-6030, or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.


[[Page 45710]]


    Issued in Renton, Washington, on September 18, 2017.
Dionne Palermo,
Acting Director, System Oversight Division, Aircraft Certification 
Service.
[FR Doc. 2017-20831 Filed 9-29-17; 8:45 am]
 BILLING CODE 4910-13-P
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