AD 2020-15-12

(a) Effective Date

    This AD is effective August 31, 2020.

(b) Affected ADs

    This AD replaces AD 2018-08-02, Amendment 39-19255 (83 FR 17746, 
April 24, 2018).

(c) Applicability

    This AD applies to Rolls-Royce Deutschland Ltd & Co KG (Type 
Certificate previously held by Rolls-Royce plc) Trent 1000-A2, Trent 
1000-AE2, Trent 1000-C2, Trent 1000-CE2, Trent 1000-D2, Trent 1000-
E2, Trent 1000-G2, Trent 1000-H2, Trent 1000-J2, Trent 1000-K2, and 
Trent 1000-L2 model turbofan engines, except those that have the 
redesigned intermediate-pressure compressor (IPC) stage 1 and stage 
2 rotor blades introduced by Rolls-Royce plc (RR) Service Bulletin 
(SB) Trent 1000 72-J941, Revision 1, dated February 6, 2019.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7230, Turbine Engine 
Compressor Section.

(e) Unsafe Condition

    This AD was prompted by IPC blade separations resulting in 
engine failures. Subsequently, the manufacturer identified cracking 
of parts in-service resulting in the need to require new inspections 
using new inspection thresholds and intervals. The manufacturer also 
determined the need to add an optional terminating action, amend the 
asymmetric power condition for engine inspection, and require an 
inspection after a cabin depressurization event. The FAA is issuing 
this AD to prevent failure of the IPC. The unsafe condition, if not 
addressed, could result in failure of one or more engines, loss of 
thrust control, and loss of the airplane.

(f) Compliance

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

(g) Required Actions

    (1) After the effective date of this AD, before exceeding the 
initial inspection thresholds and repeat inspection intervals 
specified in Table 1 of RR Alert Non-Modification Service Bulletin 
(NMSB) Trent 1000 72-AK313, Revision 1, dated August 22, 2019 (``RR 
NMSB Trent 1000 72-AK313, R1''):
    (i) Perform initial ultrasonic inspections (USIs) of the IPC 
stage 1 blade root (front face).
    (ii) Thereafter, perform repetitive USIs of the IPC stage 1 
blade root (front face).
    (iii) Use the Accomplishment Instructions, paragraph 3.A.(1)(a) 
(on-wing) or 3.A.(2)(a) and (b) (in-shop) of RR NMSB Trent 1000 72-
AK313, R1 to perform the inspections.
    (2) After the effective date of this AD, before exceeding the 
initial inspection thresholds and repeat inspection intervals 
specified in Table 2 of RR NMSB Trent 1000 72-AK313, R1:
    (i) Perform initial visual inspections of the IPC stage 2 blade 
root (front face) and IPC shaft stage 2 dovetail post (front face).
    (ii) Thereafter, perform repetitive visual inspections of the 
IPC stage 2 blade root (front face) and IPC shaft stage 2 dovetail 
post (front face).
    (iii) Use the Accomplishment Instructions, paragraph 3.B.(1)(a) 
(on-wing) or 3.B.(2)(b) (in-shop) of RR NMSB Trent 1000 72-AK313, R1 
to perform the inspections.
    (3) After the effective date of this AD, before exceeding the 
initial inspection threshold and repeat inspection intervals 
specified in Table 2 of RR NMSB Trent 1000 72-AK313, R1:
    (i) Perform initial USIs of IPC stage 2 blade root (rear face).
    (ii) Thereafter, perform repetitive USIs of IPC stage 2 blade 
root (rear face).
    (iii) Use the Accomplishment Instructions, paragraph 3.C.(1)(a) 
(on-wing) or 3.C.(2)(a) (in-shop) of RR NMSB Trent 1000 72-AK313, R1 
to perform the inspections.
    (4) After the effective date of this AD, within 5 engine flight 
cycles (FCs) after each occurrence in which any engine operates in 
asymmetric power conditions at an altitude of less than 28,000 feet, 
perform the following inspections on the engine not affected by the 
power reduction or in-flight shutdown (IFSD):
    (i) Perform initial USIs and visual inspections required by 
paragraphs (g)(1), (2), and (3) of this AD.
    (ii) Thereafter, perform the repetitive USIs and visual 
inspections required by paragraphs (g)(1), (2), and (3) of this AD.
    (iii) Use the service information and repetitive inspection 
thresholds required by paragraphs (g)(1)(iii), (2)(iii), and 
(3)(iii) to perform the inspections, as applicable.
    (5) After the effective date of this AD, within 5 engine FCs 
following a cabin depressurization event, perform the following 
inspections on both engines installed on the airplane:
    (i) Perform initial USIs and visual inspections required by 
paragraphs (g)(1), (2), and (3) of this AD.
    (ii) Thereafter, perform the repetitive USIs and visual 
inspections required by paragraphs (g)(1), (2), and (3) of this AD.
    (iii) Use the service information and repetitive inspection 
thresholds required by paragraphs (g)(1)(iii), (2)(iii), and 
(3)(iii) to perform the inspections, as applicable.
    (6) If any IPC stage 1 blade root (front face), IPC stage 2 
blade root (front face), IPC shaft stage 2 dovetail post (front 
face), or IPC stage 2 blade root (rear face) is found cracked during 
any inspection required by this AD, replace the part with a part 
eligible for installation before further flight.

(h) Terminating Action (Optional)

    Modification of an engine by installing the redesigned IPC stage 
1 and stage 2 rotor blades, using RR SB Trent 1000 72-J941, Revision 
1, dated February 6, 2019, or Initial Issue, dated December 6, 2018, 
is the terminating action for the initial and repetitive ultrasonic 
or visual inspection requirements, as applicable, of paragraph 
(g)(1) through (5) of this AD for that engine.

(i) Definition

    For the purpose of this AD, an ``asymmetric power condition'' is 
the

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operation of the airplane at an altitude of less than 28,000 feet, 
experiencing either single engine take-off, engine fault (reduced 
power on one engine), or single engine IFSD, which includes 
execution of any non-normal checklist procedure.

(j) Credit for Previous Actions

    You may take credit for the initial inspections required by 
paragraphs (g)(1) through (5) of this AD if you performed these 
inspections before the effective date of this AD using any of the 
following.
    (1) RR Alert NMSB Trent 1000 72-AJ819, Revision 3, dated April 
13, 2018, or earlier revisions;
    (2) RR NMSB Trent 1000 72-AJ814, Revision 4, dated September 28, 
2018, or earlier revisions;
    (3) RR Alert NMSB Trent 1000 72-AK313, Initial Issue, dated May 
2, 2019; or
    (4) RR Alert NMSB Trent 1000 72-AK092, Revision 3, dated 
February 28, 2019 or earlier revisions.

(k) Special Flight Permit

    Special flight permits, as described in Section 21.197 and 
Section 21.199 of the Federal Aviation Regulations (14 CFR 21.197 
and 21.199), are subject to the requirements of paragraph (k)(1) of 
this AD.
    (1) Operators who are prohibited from further flight due to a 
crack finding as a result of paragraph (g) of this AD, may perform a 
one-time non-revenue ferry flight to a location where the engine can 
be removed from service. This ferry flight must be performed without 
passengers, involve non-ETOPS operation, and consume no more than 
three FCs.
    (2) [Reserved]

(l) 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 paragraph (m)(1) of this AD. You may email your 
request to: [email protected].
    (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.

(m) Related Information

    (1) For more information about this AD, contact Stephen Elwin, 
Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: 781-238-7236; fax: 781-238-7199; email: 
[email protected].
    (2) Refer to European Union Aviation Safety Agency (EASA) AD 
2019-0250, dated October 9, 2019, for more information. You may 
examine the EASA AD in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-
2020-0009.

(n) 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) Rolls-Royce plc (RR) Alert Non-Modification Service Bulletin 
Trent 1000 72-AK313, Revision 1, dated August 22, 2019.
    (ii) RR Service Bulletin (SB) Trent 1000 72-J941, Revision 1, 
dated February 6, 2019.
    (iii) RR SB Trent 1000 72-J941, Initial Issue, dated December 6, 
2018.
    (3) For RR service information identified in this AD, contact 
Rolls-Royce Deutschland Ltd. & Co KG, Eschenweg 11, 15827 
Blankenfelde-Mahlow, Germany; phone: +49 (0) 33 708 6 0; email: 
https://www.rolls-royce.com/contact-us.aspx.
    (4) You may view this service information at FAA, Airworthiness 
Products Section, Operational Safety Branch, 1200 District Avenue, 
Burlington, MA 01803. For information on the availability of this 
material at the FAA, call 781-238-7759.
    (5) You may view this service information at the National 
Archives and Records Administration (NARA). For information on the 
availability of this material at NARA, email: [email protected], 
or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.