Voglio sapere a riguardo di…

Federal Register / Vol. 86, No. 170 / Tuesday, September 7, 2021 / Rules and Regulations IBR of the service information listed in this paragraph under 5 U.S.C. 552a 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 Rolls-Royce Non-Modification Service Bulletin Trent XWB 72K633, Initial Issue, dated August 7, 2020.
ii Reserved 3 For Rolls-Royce service information identified in this AD, contact Rolls-Royce plc, Corporate Communications, P.O. Box 31, Derby, DE24 8BJ, United Kingdom; phone:
+44 01332 242424; fax: +44 01332 249936;
website: https www.rolls-royce.com/
contact-us.aspx.
4 You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 1200 District Avenue, Burlington, MA 01803. For information on the availability of this material at the FAA, call 781 2387759.
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, email: fr.inspection@nara.gov, or go to:
https www.archives.gov/federal-register/cfr/
ibr-locations.html.
Issued on August 12, 2021.
Lance T. Gant, Director, Compliance & Airworthiness Division, Aircraft Certification Service.
FR Doc. 202119175 Filed 9321; 8:45 am BILLING CODE 491013P

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration 14 CFR Part 39
Docket No. FAA20210727; Project Identifier AD202100835R; Amendment 3921726; AD 20211908
RIN 2120AA64

Airworthiness Directives; Robinson Helicopter Company Helicopters Federal Aviation Administration FAA, DOT.
ACTION: Final rule; request for comments.
AGENCY:

The FAA is adopting a new airworthiness directive AD for certain Robinson Helicopter Company Model R44 and R44 II helicopters. This AD was prompted by reports of cracked tail rotor blades blades. This AD requires checking each blade for any crack and removing any cracked blade from service. This AD also requires removing all affected blades from service and prohibits installing any affected blade on any helicopter. The FAA is issuing this AD to address the unsafe condition on these products.

lotter on DSK11XQN23PROD with RULES1

SUMMARY:

VerDate Sep<11>2014

16:15 Sep 03, 2021

Jkt 253001

This AD is effective September 22, 2021.
The FAA must receive comments on this AD by October 22, 2021.
ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, by any of the following methods:
Federal eRulemaking Portal: Go to https www.regulations.gov. Follow the instructions for submitting comments.
Fax: 202 4932251.
Mail: U.S. Department of Transportation, Docket Operations, M
30, West Building Ground Floor, Room W12140, 1200 New Jersey Avenue SE, Washington, DC 20590.
Hand Delivery: Deliver to Mail address above between 9 a.m. and 5
p.m., Monday through Friday, except Federal holidays.
For service information identified in this final rule, contact Robinson Helicopter Company, Pete Riedl, 2901
Airport Drive, Torrance, CA 90505, United States; phone: 310 5390508;
email: eng1@robinsonheli.com; website:
https robinsonheli.com/. You may view this service information at the FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N321, Fort Worth, TX
76177. For information on the availability of this material at the FAA, call 817 2225110.
DATES:

Examining the AD Docket You may examine the AD docket at https www.regulations.gov by searching for and locating Docket No.
FAA20210727; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this final rule, any comments received, and other information. The street address for the Docket Operations is listed above.
FOR FURTHER INFORMATION CONTACT:
James Guo, Aerospace Engineer, Airframe Section, Los Angeles ACO
Branch, Compliance & Airworthiness Division, FAA, 3960 Paramount Blvd., Lakewood, CA 90712; telephone 562
6275357; email james.guo@faa.gov.
SUPPLEMENTARY INFORMATION:
Background The FAA received reports of spanwise cracks found along the leading edge of part number P/N C0293 blades, serial numbers S/N 9410 through 9909.
These affected blades were factoryinstalled or shipped as spares between March and December 2019. The cracks were found at different inspection intervals ranging from preflight inspections to 100-hour inspections. In one instance, a cracked blade was
PO 00000

Frm 00013

Fmt 4700

Sfmt 4700

49915

suspected when the pilot felt abnormal vibrations during flight; subsequent investigation determined that the blade was cracked. The cause of the cracks is a manufacturing defect in the properties of the blade skin that makes the blades prone to stress corrosion cracking. This condition, if not addressed, could result in reduced controllability and subsequent loss of control of the helicopter. The FAA is issuing this AD
to address the unsafe condition on these products.
FAAs Determination The FAA is issuing this AD because the agency has determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.
Related Service Information The FAA reviewed Robinson Helicopter Company R44 Service Bulletin SB108, dated June 30, 2021. This service bulletin specifies removing P/N
C0293 blades with S/N 9410 through 9909 from service. For continued operation until the affected blades are replaced, the service bulletin specifies a preflight inspection to be performed by the pilot.
AD Requirements This AD requires, before further flight and thereafter before each flight, checking blade P/N C0293 with S/N
9410 through 9909 inclusive, for any crack along the leading edge of the blade. An owner/operator pilot may perform this required check but must enter compliance with the applicable paragraph of this AD in the helicopter maintenance records in accordance with 14 CFR 43.9a1 through 4 and 91.417a2v. A pilot may perform this check because it involves visually checking each blade for a crack. This action can be performed equally well by a pilot or a mechanic. This check is an exception to the FAAs standard maintenance regulations. This AD also requires, before further flight, removing from service any cracked blade and prohibits installing the affected blades on any helicopter. Additionally, this AD
requires, within three months after the effective date of this AD, removing all affected blades from service.
Justification for Immediate Adoption and Determination of the Effective Date Section 553b3B of the Administrative Procedure Act APA 5
U.S.C. 551 et seq. authorizes agencies to dispense with notice and comment procedures for rules when the agency, for good cause, finds that those
E:FRFM07SER1.SGM

07SER1