05-14576. Airworthiness Directives; Rolls-Royce plc RB211-524 Series Turbofan Engines

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Final rule.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for Rolls Royce plc (RR) RB211-524 series turbofan engines with certain part number (P/N) intermediate pressure (IP) compressor stage 5 disks installed. This AD requires new reduced IP compressor stage 5 disk cyclic limits. This AD also requires removing from service affected disks that already exceed the new reduced cyclic limit, and removing other affected disks before exceeding their cyclic limits, using a drawdown schedule. This AD results from the discovery of cracks in the cooling air hole areas of the disk front spacer arm. We are issuing this AD to prevent IP compressor stage 5 disk failure, which could result in uncontained engine failure and possible damage to the airplane.

DATES:

This AD becomes effective August 30, 2005. The Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulations as of August 30, 2005.

ADDRESSES:

You can get the service information identified in this AD from Rolls-Royce plc, P.O. Box 31 Derby, DE248BJ, United Kingdom; telephone [phone]; fax [phone].

You may examine the AD docket at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA. You may examine the service information, at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or 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: http://www.archives.gov/​federal_​register/​code_​of_​federal_​regulations/​ibr_​locations.html.

FOR FURTHER INFORMATION CONTACT:

Ian Dargin, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

The FAA proposed to amend 14 CFR part 39 with a proposed AD. The proposed AD applies to (RR) RB211-524 series turbofan engines with certain P/N IP compressor stage 5 disks installed. We published the proposed AD in the Federal Register on February 2, 2005 (70 FR 5390). That action proposed to require:

• Establishing new reduced IP compressor stage 5 disk cyclic limits.
• Removing from service affected disks that already exceed the new reduced cyclic limit.
• Removing other affected disks before exceeding their cyclic limits, using a drawdown schedule.
• Allowing optional inspections at each shop visit or an on-wing eddy current inspection to extend the disk life beyond the specified life.

Examining the AD Docket

You may examine the AD Docket (including any comments and service information), by appointment, between 8:00 a.m. and 4:30 p.m., Monday through Friday, except Federal holidays. See ADDRESSES for the location.

Comments

We provided the public the opportunity to participate in the development of this AD. We received no comments on the proposal or on the determination of the cost to the public.

Conclusion

We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed.

Costs of Compliance

There are about 939 RR RB211-524 series turbofan engines of the affected design in the worldwide fleet. We estimate that this AD will affect about 35 engines installed on airplanes of U.S. registry. We also estimate that it will take about 8 work hours per engine to perform an inspection, and 300 work hours per engine to replace an IP compressor stage 5 disk. The average labor rate is $65 per work hour. Required parts will cost about $49,000 per engine. Based on these figures, we estimate the total cost of the AD to U.S. operators to be $2,415,700.

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 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); and

(3) 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 a summary of the costs to comply with this AD and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include “AD Docket No. 2002-NE-40-AD” in your request.

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 Federal Aviation Administration 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:

2005-15-13 Rolls-Royce plc: Amendment 39-14202. Docket No. 2002-NE-40-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective August 30, 2005.

Affected ADs

(b) None.

Applicability

(c) This AD applies to the Rolls-Royce plc (RR) RB211-524 series turbofan engines listed in the following Table 1, with intermediate pressure (IP) compressor stage 5 disk part numbers (P/Ns) listed in Table 2 of this AD, installed.

Table 1.—Engine Models Affected

−524B-02	−524B-B-02	−524B3-02	−524B4-02	−524B4-D-02
−524B2-19	−524B2-B-19	−524C2-19	−524C2-B-19	−524D4-19
−524D4-B-19	−524D4X-19	−524D4X-B-19	−524D4-39	−524D4-B-39
−524G2-19	−524G2-T-19	−524G3-19	−524G3-T-19	−524H2-19
−524H2-T-19	−524H-36	−524H-T-36

These engines are installed on, but not limited to, Boeing 747, 767, and Lockheed L-1011 airplanes.

Table 2.—IP Compressor Stage 5 Disk P/Ns Affected

LK60130	LK65932	LK69021	LK81269	LK83282
LK83283	UL12290	UL15743	UL15744	UL15745
UL19132	UL20785	UL20832	UL23291	UL25011
UL36821	UL36977	UL36978	UL36979	UL36980
UL36981	UL36982	UL36983	UL37078	UL37079
UL37080	UL37081	UL37082	UL37083	UL37084

Unsafe Condition

(d) This AD results from discovery of cracks in the cooling air hole areas of the disk front spacer arm. The actions specified in this AD are intended to prevent IP compressor stage 5 disk failure, which could result in uncontained engine failure and possible damage to the airplane.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done.

Cycle Limits

(f) Change the service cyclic limits contained in the Time Limits Manual, 05-10-01, for the IP compressor stage 5 discs installed in the engine models listed in the following Table 3, within 30 days after the effective date of this AD.

Table 3.—Cyclic Life Limits Without Qualifying Magnetic Particle Inspection (MPI) or Eddy Current Inspection (ECI)

Date of reduced life limit	Engine models
	-524G2, G2-T, G3, G3-T, H2, H2-T, H-36, H-T-36	-524D4, D4-B, D4-B-39, D4X, D4X-B, D4-39 CIS	-524B2, B2-B, C2, C2-B CIS	-524B-02, B-B-02, B3-02, B4-02, B4-D-02 CIS
November 30, 2002	13,500 cycles-in-service (CIS)	16,150	16,000	16,200
April 1, 2003	13,500 CIS	13,500	13,500	14,000
December 1, 2003	12,000 CIS	13,500	13,500	14,000
December 1, 2004	11,000 CIS	13,500	12,000	12,000
December 1, 2005	11,000 CIS	12,000	12,000	12,000
December 1, 2008	7,830 CIS	8,700	8,900	9,000

Optional Inspections

(g) Before December 1, 2008, optional inspections are allowed at each shop visit or on-wing to extend the disk life. Guidance for these inspections is provided in paragraphs (h) or (i) of this AD.

Optional Inspections at Shop Visit

(h) Perform optional inspections at shop visit, as follows:

(1) Remove corrosion protection from IP stage 5 disk. Information on corrosion protection removal can be found in the Engine Manual.

(2) Visual-inspect and binocular-inspect the IP stage 5 disk for corrosion pitting at the cooling air holes and defender holes in the disk front spacer arm. Follow paragraph 3.C. of the Accomplishment Instructions of RR MSB No. RB.211-72-D428, Revision 3, dated June 30, 2003. Information on disk corrosion pitting limits can be found in the Engine Manual.

(i) If the disk has corrosion pitting in excess of limits, remove the disk from service.

(ii) If the disk is free from corrosion pitting, MPI the entire disk. Information on MPI can be found in the Engine Manual. If the disk passes MPI and no cracks are found, complete all other inspections, re-apply corrosion protection to disk, and return the disk to service in accordance with the cyclic limits allowed by paragraph (k) of this AD. Information on MPI limits can be found in the Engine Manual. Information on re-applying corrosion protection can be found in RR Repair FRS5900.

(iii) If the disk has corrosion pitting within limits, ECI all disk cooling air holes, defender holes, and inner and outer faces. Follow paragraph 3.D. of the Accomplishment Instructions of RR MSB No. RB.211-72-D428, Revision 3, dated June 30, 2003. Information on corrosion pitting limits can be found in the Engine Manual. If the disk passes ECI and no cracks are found, MPI the entire disk. Information on MPI can be found in the Engine Manual. If the disk passes MPI and no cracks are found, re-apply corrosion protection to disk, and return the disk to service in accordance with the cyclic limits allowed by paragraph (k) of this AD.

Optional On-Wing EC Inspections

(i) For RB211-524B2/C2 and RB211-524B4/D4 engine models, an on-wing ECI of the IP compressor stage 5 disk may be performed only once between shop visit inspections. Follow paragraphs 3.A. through 3.F. of the Accomplishment Instructions of RR SB No. RB.211-72-E148, dated March 13, 2003, and RR SB No. RB.211-72-E150, Revision 1, dated June 4, 2003, respectively, to do the ECI. If the disk passes the ECI and no cracks are found, an extension is allowed as specified in paragraph (k) of this AD.

Definition of Shop Visit

(j) For the purposes of this AD, a shop visit is defined as the separation of an engine major case flange. This definition excludes shop visits when only field maintenance type activities are performed in lieu of performing them on-wing. (i.e., for purposes such as to perform an on-wing inspection of a tail engine installation on a Lockheed L-1011 airplane).

Cyclic Life Extension

(k) Disks that pass an optional inspection may remain in service after that inspection for the additional cycles listed in the following Table 4, until the next inspection, or December 1, 2008, or until the cyclic life limit published in the Time Limits Manual is reached, whichever occurs first.

Table 4.—Cyclic Life Extension

Engine models	-524G2, G2-T, G3, G3-T, H2, H2-T, H-36, H-T-36 (cycles)	-524D4, D4-B, D4-B-39, D4X, D4X-B, D4-39 (cycles)	-524B2, B2-B, C2, C2-B (cycles)	-524B-02, B-B-02, B3-02, B4-02, B4-D-02 (cycles)
Extension After Passing MPI	1,600	2,000	2,000	2,000
Extension After Passin In-Shop ECI	3,800	4,500	4,500	4,500
Extension After Passing On-Wing ECI	1,000	1,200	1,200	1,200

Disks That Have Been Intermixed Between Engine Models

(l) Information on intermixing disks between engine models can be found in the RR Time Limits Manual, 05-00-01.

Alternative Methods of Compliance

(m) The Manager, Engine Certification Office, has the authority to approve alternative methods of compliance for this AD if requested using the procedures found in 14 CFR 39.19.

Credit for Previous Inspections

(n) Inspections done using RR SB No. RB.211-72-E150, dated April 17, 2003 are acceptable in meeting the requirements of this AD.

Reporting Requirement

(o) Report findings of all inspections of the IP stage 5 disk using paragraph 3.B.(2) of the Accomplishment Instructions of RR ASB RB.211-72-D428, Revision 3, dated June 30, 2003. The Office of Management and Budget (OMB) has approved the reporting requirements specified in Paragraph 3.B. of the Accomplishment Instructions of RR ASB RB.211-72-D428, Revision 3, dated June 30, 2003, and assigned OMB control number 2120-0056.

Material Incorporated by Reference

(p) You must use Rolls-Royce plc Service Bulletins listed in Table 5 of this AD to perform the actions required by this AD. The Director of the Federal Register approved the incorporation by reference of this service bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You can get a copy from Rolls-Royce plc, P.O. Box 31 Derby, DE248BJ, United Kingdom; telephone [phone]; fax [phone]. You can review copies by appointment, at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA; or 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: http://www.archives.gov/​federal_​register/​code_​of_​federal_​regulations/​ibr_​locations.html.

Table 5.—Incorporation by Reference

Service bulletin	Page number shown on the page	Revision	Date shown on the page
RB.211-72-D428, including Appendices 1 through 4, dated June 30, 2003	All	3	June 30, 2003.
RB.211-72-E148 Total Pages—83	All	Original	March 13, 2003.
RB.211-72-E150 Total Pages—72	All	1	June 4, 2003.

Related Information

(q) CAA airworthiness directive 006-04-2002, dated April 2002, also addresses the subject of this AD.

Issued in Burlington, Massachusetts, on July 18, 2005.

Francis A. Favara,

Acting Manager, Engine and Propeller Directorate, Aircraft Certification Service.