Quiero saber acerca de...

Federal Register / Vol. 86, No. 139 / Friday, July 23, 2021 / Proposed Rules 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 39AIRWORTHINESS
DIRECTIVES
1. The authority citation for part 39
continues to read as follows:

Authority: 49 U.S.C. 106g, 40113, 44701.
39.13

Amended
2. The FAA amends 39.13 by:
a. Removing Airworthiness Directive AD 20210516, Amendment 3921459
86 FR 17287, April 2, 2021; and b. Adding the following new airworthiness directive:

Pratt & Whitney Division: Docket No. FAA
20210577; Project Identifier AD2021
00470E.
a Comments Due Date The FAA must receive comments on this airworthiness directive AD action by September 7, 2021.
b Affected ADs This AD replaces AD 20210516, Amendment 3921459 86 FR 17287, April 2, 2021.
c Applicability This AD applies to Pratt & Whitney Division PW PW4164, PW41641D, PW4168, PW41681D, PW4168A, PW4168A
1D, and PW4170 model turbofan engines with low-pressure turbine LPT 4th-stage air sealing ring segment assemblies, part number P/N 50N46301, P/N 50N52601, or FAAapproved equivalent part numbers, installed.

khammond on DSKJM1Z7X2PROD with PROPOSALS

d Subject Joint Aircraft System Component JASC
Code 7250, Turbine Section.
e Unsafe Condition This AD was prompted by several reports from the manufacturer concerning LPT 4thstage vane cluster assemblies leaning back and notching into the rotating LPT 4th-stage blades, causing some blades to fracture and release. A manufacturer investigation into those reports determined that the leaning back of the LPT 4th-stage vane cluster assemblies was caused by damage to the LPT
4th-stage air sealing ring segment assemblies.
The FAA is issuing this AD to prevent damage to the LPT 4th-stage air sealing ring segment assemblies, the LPT case, and the LPT 4th-stage blades. The unsafe condition, if not addressed, could result in uncontained release of the LPT 4th-stage blades, damage to the engine, and damage to the airplane.

VerDate Sep<11>2014

16:27 Jul 22, 2021

Jkt 253001

f Compliance Comply with this AD within the compliance times specified, unless already done.
g Required Actions 1 For affected engines that have either the Talon IIA outer combustion chamber assembly, P/N 51J100 or P/N 51J382, or the Talon IIB outer combustion chamber assembly, P/N 51J381 or P/N 51J500, installed, at the next engine shop visit after the effective date of this AD, remove from service the LPT 4th-stage air sealing ring segment assemblies, P/N 50N46301, P/N
50N52601, or FAA-approved equivalent part numbers, and replace with parts eligible for installation.
2 For affected engines not referenced in paragraph g1 of this AD, at the next LPT
overhaul after the effective date of this AD, remove from service the LPT 4th-stage air sealing ring segment assemblies, P/N
50N46301, P/N 50N52601, or FAAapproved equivalent part numbers, and replace with parts eligible for installation.
3 For all affected engines, at each LPT
overhaul after compliance with the required actions in paragraphs g1 or 2 of this AD, remove from service the LPT 4th-stage air sealing ring segment assemblies, P/N
50N52601 or FAA-approved equivalent part numbers, and replace with parts eligible for installation.
4 During each replacement of the LPT
4th-stage air sealing ring segment assemblies required by paragraphs g1 through 3 of this AD, perform a dimensional inspection of the LPT case for bulging in accordance with the Accomplishment Instructions, paragraph 2, of PW Alert Service Bulletin No. PW4G
100A72262 Revision No. 1, dated September 3, 2020 the ASB.
5 If, during the dimensional inspection of the LPT case required by paragraph g4 of this AD, any LPT case found to be outside the serviceable limits specified in Table 1:
Serviceable Limits and Repairs of the ASB, repair or replace the LPT case before further flight.
h Definitions For the purpose of this AD:
1 An engine shop visit is the induction of an engine into the shop for maintenance involving the separation of pairs of major mating engine flanges H through P. The separation of engine flanges solely for the purpose of transportation without subsequent engine maintenance does not constitute an engine shop visit.
2 An LPT overhaul is when the LPT
rotor is removed from the engine, all four disks are removed from the LPT rotor, and all blades are removed from the disks.
3 Parts eligible for installation are LPT
4th-stage air sealing ring segment assemblies, P/N 50N52601, or FAA-approved equivalent part numbers, with zero flight cycles since new or with a P/N not mentioned in this AD.
i Credit for Previous Actions You may take credit for the dimensional inspection of the LPT case for bulging required by paragraph g4 of this AD if the inspection was performed before the effective
PO 00000

Frm 00003

Fmt 4702

Sfmt 4702

38943

date of this AD using PW ASB No. PW4G
100A72262 Original Issue, dated October 22, 2019.
j Alternative Methods of Compliance AMOCs 1 The Manager, ECO Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14
CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the certification office, send it to the attention of the person identified in Related Information.
Information may be emailed to: ANE-ADAMOC@faa.gov.
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.
k Related Information 1 For more information about this AD, contact Carol Nguyen, Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781
2387655; fax: 781 2387199; email:
carol.nguyen@faa.gov.
2 For service information identified in this AD, contact Pratt & Whitney, 400 Main Street, East Hartford, CT 06118; phone: 800
5650140; email: help24@prattwhitney.com;
website: https prattwhitney.com. You may view this referenced 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.
Issued on July 16, 2021.
Lance T. Gant, Director, Compliance & Airworthiness Division, Aircraft Certification Service.
FR Doc. 202115518 Filed 72221; 8:45 am BILLING CODE 491013P

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration 14 CFR Part 39
Docket No. FAA20210574; Project Identifier 2019SW073AD
RIN 2120AA64

Airworthiness Directives; Helicopteres Guimbal Helicopters Federal Aviation Administration FAA, DOT.
ACTION: Notice of proposed rulemaking NPRM.
AGENCY:

The FAA proposes to adopt a new airworthiness directive AD for certain Helicopteres Guimbal Model CABRI G2 helicopters. This proposed AD was prompted by a report that, SUMMARY:

E:FRFM23JYP1.SGM

23JYP1