Airworthiness Directives; The Enstrom Helicopter Corporation, 12308-12310 [2017-03950]

Download as PDF 12308 Federal Register / Vol. 82, No. 40 / Thursday, March 2, 2017 / Proposed Rules (2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service. (h) Related Information Refer to MCAI European Aviation Safety Agency (EASA) AD No.: 2017–0005, dated January 10, 2017, for related information. You may examine the MCAI on the Internet at https://www.regulations.gov by searching for and locating Docket No. FAA–2017–0156. For service information related to this AD, ˇ ˇ contact ZLIN AIRCRAFT a.s., Letiste 1887, 765 02 Otrokovice, Czech Republic, telephone: +420 725 266 711; fax: +420 226 013 830; email: info@zlinaircraft.eu, Internet: https://www.zlinaircraft.eu. You may review copies of the referenced service information at the FAA, Small Airplane Directorate, 901 Locust, Kansas City, Missouri 64106. For information on the availability of this material at the FAA, call (816) 329–4148. Issued in Kansas City, Missouri, on February 17, 2017. Pat Mullen, Acting Manager, Small Airplane Directorate, Aircraft Certification Service. [FR Doc. 2017–03965 Filed 3–1–17; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2017–0141; Directorate Identifier 2016–SW–067–AD] RIN 2120–AA64 Airworthiness Directives; The Enstrom Helicopter Corporation Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: We propose to supersede airworthiness directive (AD) 2015–08– 51 for Enstrom Helicopter Corporation (Enstrom) Model F–28A, 280, F–28C, F– 28C–2, F–28C–2R, 280C, F–28F, F–28F– R, 280F, 280FX, and 480 helicopters. AD 2015–08–51 requires an inspection of the main rotor spindle (spindle) and reporting the inspection results to the FAA. This proposed AD was prompted by additional reports of cracked spindles and would require establishing a life limit and a recurring inspection. These proposed actions are intended to prevent the unsafe condition on these products. pmangrum on DSK3GDR082PROD with PROPOSALS SUMMARY: VerDate Sep<11>2014 13:51 Mar 01, 2017 Jkt 241001 We must receive comments on this proposed AD by May 1, 2017. ADDRESSES: You may send comments by any of the following methods: • Federal eRulemaking Docket: Go to https://www.regulations.gov. Follow the online instructions for sending your comments electronically. • Fax: 202–493–2251. • Mail: Send comments to the U.S. Department of Transportation, Docket Operations, M–30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590–0001. • Hand Delivery: Deliver to the ‘‘Mail’’ address between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. DATES: 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–2017– 0141; or in person at the Docket Operations Office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the economic evaluation, any comments received and other information. The street address for the Docket Operations Office (telephone 800–647–5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt. For service information identified in this proposed rule, contact Enstrom Helicopter Corporation, 2209 22nd Street, Menominee, MI; telephone (906) 863–1200; fax (906) 863–6821; or at www.enstromhelicopter.com. You may review service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N–321, Fort Worth, TX 76177. FOR FURTHER INFORMATION CONTACT: Monica Nemecek, Continued Operational Safety Program Manager, Chicago Aircraft Certification Office, Small Airplane Directorate, FAA, 2300 East Devon Ave., Des Plaines, IL 60018; (847) 294–7618; email 9-AGL-CHI-ACOCOS@faa.gov. SUPPLEMENTARY INFORMATION: Comments Invited We invite you to participate in this rulemaking by submitting written comments, data, or views. We also invite comments relating to the economic, environmental, energy, or federalism impacts that might result from adopting the proposals in this document. The most helpful comments reference a specific portion of the PO 00000 Frm 00008 Fmt 4702 Sfmt 4702 proposal, explain the reason for any recommended change, and include supporting data. To ensure the docket does not contain duplicate comments, commenters should send only one copy of written comments, or if comments are filed electronically, commenters should submit only one time. We will file in the docket all comments that we receive, as well as a report summarizing each substantive public contact with FAA personnel concerning this proposed rulemaking. Before acting on this proposal, we will consider all comments we receive on or before the closing date for comments. We will consider comments filed after the comment period has closed if it is possible to do so without incurring expense or delay. We may change this proposal in light of the comments we receive. Discussion On May 8, 2015, we issued AD 2015– 08–51, Amendment 39–18160 (80 FR 28172, May 18, 2015), which was sent previously as an emergency AD to all known U.S. owners and operators of Enstrom Model F–28A, 280, F–28C, F– 28C–2, F–28C–2R, 280C, F–28F, F–28F– R, 280F, 280FX, and 480 helicopters. AD 2015–08–51 applies to helicopters with a spindle part number (P/N) 28– 14282–11 or 28–14282–13 installed and requires conducting a one-time magnetic particle inspection (MPI) of the spindle for cracks and reporting the inspection results to the FAA. AD 2015– 08–51 was prompted by a fatal accident and reports of spindles with cracks. The actions of AD 2015–08–51 are intended to detect a crack in a spindle and prevent loss of a main rotor blade and subsequent loss of control of the helicopter. Actions Since AD 2015–08–51 Was Issued Since we issued AD 2015–08–51, we received additional reports of cracked spindles. Additionally, Enstrom revised its service information to reduce the time for the initial MPI from 3,500 hours TIS to 1,500 hours TIS and extend the compliance time for a recurring MPI of the spindles from 300 hours TIS to 500 hours TIS. Based on a review of the inservice data and a fatigue analysis, the FAA determined a life limit and repetitive MPIs were necessary to reduce the risk of a crack developing in a spindle. We also determined the reporting requirement in AD 2015–08– 51 is no longer necessary. We issued AD 2015–08–51 as interim action; this proposed AD would provide long-term requirements to prevent a spindle failure. Accordingly, this E:\FR\FM\02MRP1.SGM 02MRP1 Federal Register / Vol. 82, No. 40 / Thursday, March 2, 2017 / Proposed Rules proposed AD would require an MPI of the spindle every 500 hours TIS until the spindle reaches its new life limit of 1,500 hours TIS. These proposed actions are intended to detect a crack in a spindle and prevent loss of a main rotor blade and subsequent loss of control of the helicopter. FAA’s Determination We are proposing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of these same type designs. Related Service Information We reviewed Enstrom Service Directive Bulletin No. 0119, Revision 3, dated June 24, 2016, for Model F–28A, F–28C, F–28F, 280, 280C, 280F, and 280FX helicopters with a spindle P/N 28–14282–11 or 28–14282–13. We also reviewed Enstrom Service Directive Bulletin No. T–050, Revision 3, dated June 24, 2016, for Model 480 helicopters, serial numbers 5001 through 5004 and 5006, and with a spindle P/N 28–14282–13, except those aircraft modified with tension-torsion straps. Both service directive bulletins specify sending the spindle to Enstrom for an MPI before the spindle reaches 1,500 hours time-in-service (TIS), or within 5 hours TIS for those spindles with 1,500 or more hours TIS. Thereafter, the service directive bulletins specify returning the spindle to Enstrom for an MPI every 500 hours. pmangrum on DSK3GDR082PROD with PROPOSALS Proposed AD Requirements This proposed AD would require establishing a life limit of 1,500 hours TIS for spindle P/Ns 28–14282–11 and 28–14282–13. This proposed AD would also require an initial and recurring MPI of the spindles. Differences Between This Proposed AD and the Service Information This proposed AD would require establishing a spindle life limit of 1,500 hours TIS. The service information does not specify a life limit. This proposed AD would require that the MPI be conducted by a Level II or Level III inspector or equivalent. The service information specifies sending the spindle to Enstrom for an MPI. This proposed AD would require an initial MPI before further flight for a spindle with 500 or more hours TIS, unless an MPI has been done within the last 500 hours TIS. The service information specifies an initial MPI compliance time of within 5 hours TIS for a spindle with 1,500 or more hours TIS. VerDate Sep<11>2014 13:51 Mar 01, 2017 Jkt 241001 Costs of Compliance We estimate that this proposed AD would affect 323 helicopters of U.S. Registry. We estimate that operators may incur the following costs in order to comply with this AD. Labor costs are estimated at $85 per work-hour. Inspecting the spindles would take about 15 work-hours for an estimated cost of $1,275 per helicopter and $411,825 for the U.S. fleet per inspection cycle. Replacing a cracked spindle would cost $8,164 for parts and no additional work-hours. Replacing a set of three spindles that have reached their life limit would take about 14 work-hours and parts would cost $17,500 for a total cost of $18,690 per helicopter. 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. Regulatory Findings We 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, I certify this proposed regulation: 1. Is not a ‘‘significant regulatory action’’ under Executive Order 12866; 2. Is not a ‘‘significant rule’’ under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 3. Will not affect intrastate aviation in Alaska to the extent that it justifies making a regulatory distinction; and 4. Will not have a significant economic impact, positive or negative, PO 00000 Frm 00009 Fmt 4702 Sfmt 4702 12309 on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. We prepared an economic evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket. 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 removing Airworthiness Directive (AD) 2015–08–51, Amendment 39–18160 (80 FR 28172, May 18, 2015), and adding the following new AD: ■ The Enstrom Helicopter Corporation (Enstrom): Docket No. FAA–2017–0141; Directorate Identifier 2016–SW–067–AD. (a) Applicability This AD applies to Enstrom Model F–28A, 280, F–28C, F–28C–2, F–28C–2R, 280C, F– 28F, F–28F–R, 280F, and 280FX helicopters, all serial numbers; and Enstrom Model 480 helicopters, serial numbers 5001 through 5006; with a main rotor spindle (spindle) part number (P/N) 28–14282–11 or 28–14282–13, installed, certificated in any category. (b) Unsafe Condition This AD defines the unsafe condition as a crack in a spindle, which, if not detected, could result in loss of a main rotor blade and subsequent loss of control of the helicopter. (c) Affected ADs This AD supersedes AD 2015–08–51, Amendment 39–18160 (80 FR 28172, May 18, 2015). (d) Comments Due Date We must receive comments by May 1, 2017. (e) Compliance You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time. (f) Required Actions (1) Before further flight, remove from service any spindle P/N 28–14282–11 or 28– 14282–13 that has 1,500 or more hours timein-service (TIS). If the hours TIS of a spindle is unknown, use the TIS of the helicopter. E:\FR\FM\02MRP1.SGM 02MRP1 12310 Federal Register / Vol. 82, No. 40 / Thursday, March 2, 2017 / Proposed Rules Thereafter, remove from service any spindle P/N 28–14282–11 or 28–14282–13 before accumulating 1,500 hours TIS. (2) For each spindle with 500 or more hours TIS, using the hours TIS of the helicopter if the hours TIS of the spindle is unknown: (i) Before further flight, unless already done within the last 500 hours TIS, conduct a magnetic particle inspection (MPI) of the spindle for a crack, paying particular attention to the threaded portion of the spindle. The MPI of the spindle must be conducted by a Level II or Level III inspector qualified in the MPI in the Aeronautics Sector according to the EN4179 or NAS410 standard or equivalent. If there is a crack in the spindle, replace it with an airworthy spindle before further flight. (ii) Thereafter at intervals not to exceed 500 hours TIS, repeat the MPI specified in paragraph (f)(2)(i) of this AD. (g) Alternative Methods of Compliance (AMOCs) (1) The Manager, Chicago Aircraft Certification Office, FAA, may approve AMOCs for this AD. Send your proposal to: Monica Nemecek, Continued Operational Safety Program Manager, Chicago Aircraft Certification Office, Small Airplane Directorate, FAA, 2300 East Devon Ave., Des Plaines, IL 60018; (847) 294–7618; email 9AGL-CHI-ACO-COS@faa.gov. (2) For operations conducted under a 14 CFR part 119 operating certificate or under 14 CFR part 91, subpart K, we suggest that you notify your principal inspector, or lacking a principal inspector, the manager of the local flight standards district office or certificate holding district office before operating any aircraft complying with this AD through an AMOC. (3) AMOCs approved previously in accordance with AD 2015–08–51, Amendment 39–18160 (80 FR 28172, May 18, 2015), are approved as AMOCs for the corresponding requirements in paragraph (f) of this AD. pmangrum on DSK3GDR082PROD with PROPOSALS (h) Additional Information Enstrom Service Directive Bulletin Nos. 0119 and T–050, both Revision 3 and both dated June 24, 2016, which are not incorporated by reference, contain additional information about the subject of this AD. For service information identified in this AD, contact Enstrom Helicopter Corporation, 2209 22nd Street, Menominee, MI; telephone (906) 863–1200; fax (906) 863–6821; or at www.enstromhelicopter.com. You may review the service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N– 321, Fort Worth, TX 76177. (i) Subject Joint Aircraft Service Component (JASC) Code: 6220, Main Rotor Head. VerDate Sep<11>2014 13:51 Mar 01, 2017 Jkt 241001 Issued in Fort Worth, Texas, on February 16, 2017. Lance T. Gant, Manager, Rotorcraft Directorate, Aircraft Certification Service. [FR Doc. 2017–03950 Filed 3–1–17; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2017–0157; Directorate Identifier 2016–CE–039–AD] RIN 2120–AA64 Airworthiness Directives; Piper Aircraft, Inc. Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: We propose to supersede Airworthiness Directive (AD) 69–13–03, which applies to all Piper Aircraft, Inc. Models PA–23, PA–23–160, PA–23–235, PA–23–250, PA–E23–250, and PA–30 airplanes. AD 69–13–03 currently requires inspection of the heater exhaust extension, replacement of the extension as necessary, and overhaul of the combustion heater assembly. Since we issued AD 69–13–03, we proposed an AD that applies to the Meggitt (Troy), Inc. combustion heaters, and the proposed combustion heater AD would incorporate corrective actions for the heater that contradict the overhaul requirement of AD 69–13–03. This proposed AD would retain the inspection of the heater exhaust extension, with replacement of the extension as necessary, and remove the overhaul requirement of the combustion heater assembly. We are proposing this AD to correct the unsafe condition on these products. DATES: We must receive comments on this proposed AD by April 17, 2017. 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 SUMMARY: PO 00000 Frm 00010 Fmt 4702 Sfmt 4702 p.m., Monday through Friday, except Federal holidays. 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–2017– 0157; 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 proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (phone: 800–647–5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt. FOR FURTHER INFORMATION CONTACT: Scott Hopper, Aerospace Engineer, FAA, Atlanta Aircraft Certification Office, 1701 Columbia Avenue, College Park, Georgia 30337; phone: (404) 474– 5535; fax: (404) 474–5606; email: scott.hopper@faa.gov. SUPPLEMENTARY INFORMATION: Comments Invited We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include ‘‘Docket No. FAA–2017–9157; Directorate Identifier 2016–CE–039–AD’’ at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments. We will post all comments we receive, without change, to https:// www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD. Discussion We issued AD 69–13–03, Amendment 39–1749 (38 FR 33765, December 7, 1973) (‘‘AD 69–13–03’’), for certain Piper Aircraft, Inc. Models PA–23, PA– 23–160, PA–23–235, PA–23–250, PA– E23–250, and PA–30 airplanes. AD 69– 13–03 requires inspection of the heater exhaust extension to determine if it is mild steel or stainless steel, repetitive inspections of the mild steel extensions for deterioration, replacing the extension as necessary, and overhaul of the combustion heater assembly. AD 69–13–03 resulted from the potential of carbon monoxide entering the airplane E:\FR\FM\02MRP1.SGM 02MRP1

Agencies

[Federal Register Volume 82, Number 40 (Thursday, March 2, 2017)]
[Proposed Rules]
[Pages 12308-12310]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-03950]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-0141; Directorate Identifier 2016-SW-067-AD]
RIN 2120-AA64


Airworthiness Directives; The Enstrom Helicopter Corporation

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: We propose to supersede airworthiness directive (AD) 2015-08-
51 for Enstrom Helicopter Corporation (Enstrom) Model F-28A, 280, F-
28C, F-28C-2, F-28C-2R, 280C, F-28F, F-28F-R, 280F, 280FX, and 480 
helicopters. AD 2015-08-51 requires an inspection of the main rotor 
spindle (spindle) and reporting the inspection results to the FAA. This 
proposed AD was prompted by additional reports of cracked spindles and 
would require establishing a life limit and a recurring inspection. 
These proposed actions are intended to prevent the unsafe condition on 
these products.

DATES: We must receive comments on this proposed AD by May 1, 2017.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Docket: Go to https://www.regulations.gov. Follow the online instructions for sending your 
comments electronically.
     Fax: 202-493-2251.
     Mail: Send comments to the U.S. Department of 
Transportation, Docket Operations, M-30, West Building Ground Floor, 
Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590-0001.
     Hand Delivery: Deliver to the ``Mail'' address between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

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-2017-
0141; or in person at the Docket Operations Office between 9 a.m. and 5 
p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this proposed AD, the economic evaluation, any comments 
received and other information. The street address for the Docket 
Operations Office (telephone 800-647-5527) is in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.
    For service information identified in this proposed rule, contact 
Enstrom Helicopter Corporation, 2209 22nd Street, Menominee, MI; 
telephone (906) 863-1200; fax (906) 863-6821; or at 
www.enstromhelicopter.com. You may review service information at the 
FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood 
Pkwy., Room 6N-321, Fort Worth, TX 76177.

FOR FURTHER INFORMATION CONTACT: Monica Nemecek, Continued Operational 
Safety Program Manager, Chicago Aircraft Certification Office, Small 
Airplane Directorate, FAA, 2300 East Devon Ave., Des Plaines, IL 60018; 
(847) 294-7618; email 9-AGL-CHI-ACO-COS@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to participate in this rulemaking by submitting 
written comments, data, or views. We also invite comments relating to 
the economic, environmental, energy, or federalism impacts that might 
result from adopting the proposals in this document. The most helpful 
comments reference a specific portion of the proposal, explain the 
reason for any recommended change, and include supporting data. To 
ensure the docket does not contain duplicate comments, commenters 
should send only one copy of written comments, or if comments are filed 
electronically, commenters should submit only one time.
    We will file in the docket all comments that we receive, as well as 
a report summarizing each substantive public contact with FAA personnel 
concerning this proposed rulemaking. Before acting on this proposal, we 
will consider all comments we receive on or before the closing date for 
comments. We will consider comments filed after the comment period has 
closed if it is possible to do so without incurring expense or delay. 
We may change this proposal in light of the comments we receive.

Discussion

    On May 8, 2015, we issued AD 2015-08-51, Amendment 39-18160 (80 FR 
28172, May 18, 2015), which was sent previously as an emergency AD to 
all known U.S. owners and operators of Enstrom Model F-28A, 280, F-28C, 
F-28C-2, F-28C-2R, 280C, F-28F, F-28F-R, 280F, 280FX, and 480 
helicopters. AD 2015-08-51 applies to helicopters with a spindle part 
number (P/N) 28-14282-11 or 28-14282-13 installed and requires 
conducting a one-time magnetic particle inspection (MPI) of the spindle 
for cracks and reporting the inspection results to the FAA. AD 2015-08-
51 was prompted by a fatal accident and reports of spindles with 
cracks. The actions of AD 2015-08-51 are intended to detect a crack in 
a spindle and prevent loss of a main rotor blade and subsequent loss of 
control of the helicopter.

Actions Since AD 2015-08-51 Was Issued

    Since we issued AD 2015-08-51, we received additional reports of 
cracked spindles. Additionally, Enstrom revised its service information 
to reduce the time for the initial MPI from 3,500 hours TIS to 1,500 
hours TIS and extend the compliance time for a recurring MPI of the 
spindles from 300 hours TIS to 500 hours TIS. Based on a review of the 
in-service data and a fatigue analysis, the FAA determined a life limit 
and repetitive MPIs were necessary to reduce the risk of a crack 
developing in a spindle. We also determined the reporting requirement 
in AD 2015-08-51 is no longer necessary.
    We issued AD 2015-08-51 as interim action; this proposed AD would 
provide long-term requirements to prevent a spindle failure. 
Accordingly, this

[[Page 12309]]

proposed AD would require an MPI of the spindle every 500 hours TIS 
until the spindle reaches its new life limit of 1,500 hours TIS. These 
proposed actions are intended to detect a crack in a spindle and 
prevent loss of a main rotor blade and subsequent loss of control of 
the helicopter.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of these same type 
designs.

Related Service Information

    We reviewed Enstrom Service Directive Bulletin No. 0119, Revision 
3, dated June 24, 2016, for Model F-28A, F-28C, F-28F, 280, 280C, 280F, 
and 280FX helicopters with a spindle P/N 28-14282-11 or 28-14282-13. We 
also reviewed Enstrom Service Directive Bulletin No. T-050, Revision 3, 
dated June 24, 2016, for Model 480 helicopters, serial numbers 5001 
through 5004 and 5006, and with a spindle P/N 28-14282-13, except those 
aircraft modified with tension-torsion straps. Both service directive 
bulletins specify sending the spindle to Enstrom for an MPI before the 
spindle reaches 1,500 hours time-in-service (TIS), or within 5 hours 
TIS for those spindles with 1,500 or more hours TIS. Thereafter, the 
service directive bulletins specify returning the spindle to Enstrom 
for an MPI every 500 hours.

Proposed AD Requirements

    This proposed AD would require establishing a life limit of 1,500 
hours TIS for spindle P/Ns 28-14282-11 and 28-14282-13. This proposed 
AD would also require an initial and recurring MPI of the spindles.

Differences Between This Proposed AD and the Service Information

    This proposed AD would require establishing a spindle life limit of 
1,500 hours TIS. The service information does not specify a life limit.
    This proposed AD would require that the MPI be conducted by a Level 
II or Level III inspector or equivalent. The service information 
specifies sending the spindle to Enstrom for an MPI.
    This proposed AD would require an initial MPI before further flight 
for a spindle with 500 or more hours TIS, unless an MPI has been done 
within the last 500 hours TIS. The service information specifies an 
initial MPI compliance time of within 5 hours TIS for a spindle with 
1,500 or more hours TIS.

Costs of Compliance

    We estimate that this proposed AD would affect 323 helicopters of 
U.S. Registry. We estimate that operators may incur the following costs 
in order to comply with this AD. Labor costs are estimated at $85 per 
work-hour. Inspecting the spindles would take about 15 work-hours for 
an estimated cost of $1,275 per helicopter and $411,825 for the U.S. 
fleet per inspection cycle. Replacing a cracked spindle would cost 
$8,164 for parts and no additional work-hours. Replacing a set of three 
spindles that have reached their life limit would take about 14 work-
hours and parts would cost $17,500 for a total cost of $18,690 per 
helicopter.

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.

Regulatory Findings

    We 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, I certify this proposed regulation:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979);
    3. Will not affect intrastate aviation in Alaska to the extent that 
it justifies making a regulatory distinction; 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.
    We prepared an economic evaluation of the estimated costs to comply 
with this proposed AD and placed it in the AD docket.

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 removing Airworthiness Directive (AD) 
2015-08-51, Amendment 39-18160 (80 FR 28172, May 18, 2015), and adding 
the following new AD:

The Enstrom Helicopter Corporation (Enstrom): Docket No. FAA-2017-
0141; Directorate Identifier 2016-SW-067-AD.

(a) Applicability

    This AD applies to Enstrom Model F-28A, 280, F-28C, F-28C-2, F-
28C-2R, 280C, F-28F, F-28F-R, 280F, and 280FX helicopters, all 
serial numbers; and Enstrom Model 480 helicopters, serial numbers 
5001 through 5006; with a main rotor spindle (spindle) part number 
(P/N) 28-14282-11 or 28-14282-13, installed, certificated in any 
category.

(b) Unsafe Condition

    This AD defines the unsafe condition as a crack in a spindle, 
which, if not detected, could result in loss of a main rotor blade 
and subsequent loss of control of the helicopter.

(c) Affected ADs

    This AD supersedes AD 2015-08-51, Amendment 39-18160 (80 FR 
28172, May 18, 2015).

(d) Comments Due Date

    We must receive comments by May 1, 2017.

(e) Compliance

    You are responsible for performing each action required by this 
AD within the specified compliance time unless it has already been 
accomplished prior to that time.

(f) Required Actions

    (1) Before further flight, remove from service any spindle P/N 
28-14282-11 or 28-14282-13 that has 1,500 or more hours time-in-
service (TIS). If the hours TIS of a spindle is unknown, use the TIS 
of the helicopter.

[[Page 12310]]

Thereafter, remove from service any spindle P/N 28-14282-11 or 28-
14282-13 before accumulating 1,500 hours TIS.
    (2) For each spindle with 500 or more hours TIS, using the hours 
TIS of the helicopter if the hours TIS of the spindle is unknown:
    (i) Before further flight, unless already done within the last 
500 hours TIS, conduct a magnetic particle inspection (MPI) of the 
spindle for a crack, paying particular attention to the threaded 
portion of the spindle. The MPI of the spindle must be conducted by 
a Level II or Level III inspector qualified in the MPI in the 
Aeronautics Sector according to the EN4179 or NAS410 standard or 
equivalent. If there is a crack in the spindle, replace it with an 
airworthy spindle before further flight.
    (ii) Thereafter at intervals not to exceed 500 hours TIS, repeat 
the MPI specified in paragraph (f)(2)(i) of this AD.

(g) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Chicago Aircraft Certification Office, FAA, may 
approve AMOCs for this AD. Send your proposal to: Monica Nemecek, 
Continued Operational Safety Program Manager, Chicago Aircraft 
Certification Office, Small Airplane Directorate, FAA, 2300 East 
Devon Ave., Des Plaines, IL 60018; (847) 294-7618; email 9-AGL-CHI-ACO-COS@faa.gov.
    (2) For operations conducted under a 14 CFR part 119 operating 
certificate or under 14 CFR part 91, subpart K, we suggest that you 
notify your principal inspector, or lacking a principal inspector, 
the manager of the local flight standards district office or 
certificate holding district office before operating any aircraft 
complying with this AD through an AMOC.
    (3) AMOCs approved previously in accordance with AD 2015-08-51, 
Amendment 39-18160 (80 FR 28172, May 18, 2015), are approved as 
AMOCs for the corresponding requirements in paragraph (f) of this 
AD.

(h) Additional Information

    Enstrom Service Directive Bulletin Nos. 0119 and T-050, both 
Revision 3 and both dated June 24, 2016, which are not incorporated 
by reference, contain additional information about the subject of 
this AD. For service information identified in this AD, contact 
Enstrom Helicopter Corporation, 2209 22nd Street, Menominee, MI; 
telephone (906) 863-1200; fax (906) 863-6821; or at 
www.enstromhelicopter.com. You may review the service information at 
the FAA, Office of the Regional Counsel, Southwest Region, 10101 
Hillwood Pkwy., Room 6N-321, Fort Worth, TX 76177.

(i) Subject

    Joint Aircraft Service Component (JASC) Code: 6220, Main Rotor 
Head.


    Issued in Fort Worth, Texas, on February 16, 2017.
Lance T. Gant,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2017-03950 Filed 3-1-17; 8:45 am]
BILLING CODE 4910-13-P
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.