E7-13090. Airworthiness Directives; Rolls-Royce Deutschland Tay 611-8, Tay 611-8C, Tay 620-15, Tay 650-15, and Tay 651-54 Turbofan Engines

AGENCY:

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

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) for Rolls-Royce Deutschland (RRD) Tay 611-8, Tay 620-15, Tay 650-15, and Tay 651-54 turbofan engines. That AD currently requires initial and repetitive visual inspections of all ice-impact panels and fillers in the low pressure (LP) compressor case for certain conditions and replacing as necessary, any or all panels. This proposed AD would require the same initial and repetitive inspections, provide terminating action to those repetitive actions, and add the Tay 611-8C turbofan engine to the applicability. This proposed AD results from RRD introducing new LP compressor case ice-impact panels with additional retention features, to these Tay turbofan engines. We are proposing this AD to prevent release of ice-impact panels due to improper bonding that can result in loss of thrust in both engines.

DATES:

We must receive any comments on this proposed AD by September 4, 2007.

ADDRESSES:

Use one of the following addresses to comment on this proposed AD.

• DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
• Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
• 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 p.m., Monday through Friday, except Federal holidays.
• Fax: [phone].

Contact Rolls-Royce Deutschland Ltd & Co KG, Eschenweg 11, D-15827 Dahlewitz, Germany; telephone [phone]; fax [phone], for the service information referenced in this proposed AD.

FOR FURTHER INFORMATION CONTACT:

Jason Yang, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; e-mail: [e-mail]; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2007-27811; Directorate Identifier 2004-NE-11-AD” in the subject line of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this proposed AD. Using the search function of the DMS Web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78) or you may visit http://dms.dot.gov.

Examining the AD Docket

You may examine the AD docket on the Internet at http://dms.dot.gov; 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 regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone [phone]) is the same as the Mail address provided in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

Discussion

On December 22, 2004, the FAA issued AD 2004-26-10, Amendment 39-13922 (70 FR 1172, January 6, 2005). That AD requires initial and repetitive visual inspections of all ice-impact panels and fillers in the LP compressor case for certain conditions and replacing as necessary, any or all panels. That AD also introduced a new compliance date of no later than March 1, 2005, to have all but one engine on each airplane in compliance with the polysulfide bonding of panels.

Actions Since AD 2004-26-10 Was Issued

Since AD 2004-26-10 was issued, the Luftfahrt-Bundesamt, (LBA), which is the airworthiness authority for Germany, notified us that RRD has introduced new LP compressor case ice-impact panels with additional retention features. The LP compressor case must be reworked to accept the new ice-impact panels, by December 31, 2011.

Relevant Service Information

We have reviewed and approved the technical contents of RRD Alert Service Bulletin (ASB) No. TAY-72-A1643, Revision 1, dated November 2, 2005, and ASB No. TAY-72-A1650, dated November 2, 2005. These ASBs describe procedures for reworking the LP compressor case and installing new ice-impact panels with additional retention features. The LBA classified these ASBs as mandatory and issued AD D-2004-313R5 in order to ensure the airworthiness of these Tay turbofan engines in Germany.

Bilateral Agreement Information

These engine models are manufactured in Germany and are type certificated for operation in the United States under the provisions of Section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Under this bilateral airworthiness agreement, the LBA kept us informed of the situation described above. We have examined the findings of the LBA, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to exist or develop on other products of this same type design. We are proposing this AD, which would require:

• Adding the Tay 611-8C turbofan engine, serial numbers below 85078, to the applicability.
• Initial visual inspection of all ice-impact panels and fillers in the LP compressor case for certain conditions and replacing as necessary, any or all panels, before further flight, if not previously done.
• Repetitive visual inspections of all ice-impact panels and fillers in the LP compressor case for certain conditions and replacing as necessary, any or all panels.
• Having all but one engine on each airplane in compliance with the polysulfide bonding of panels.
• Rework of LP compressor cases and installation of new LP compressor case ice-impact panels with additional retention features by December 31, 2011, as mandatory terminating action to the repetitive visual inspections, repairs, and replacements.

The proposed AD would require that you do these actions using the service information described previously.

Costs of Compliance

We estimate that this proposed AD would affect about 1,085 engines installed on airplanes of U.S. registry. We also estimate that it would take about 2.5 work-hours per engine to perform an inspection, and about 12 work-hours to perform a repair as proposed. The average labor rate is $80 per work-hour. Required terminating action parts would cost about $7,500 per engine. Based on these figures, for the proposed AD, we estimate:

• The cost of one inspection to the U.S. fleet to be $217,000.
• The cost of a repair to the U.S fleet to be $1,041,600.
• The cost of parts to the U.S. fleet for terminating action, to be $8,137,500.

Docket Number Change

We are transferring the docket for this AD to the Docket Management System as part of our ongoing docket management consolidation efforts. The new Docket No. is FAA-2007-27811. The old Docket No. became the Directorate Identifier, which is 2004-NE-11-AD. This AD might get logged into the DMS docket, ahead of the previously collected documents from the old docket file, as we are in the process of sending those items to the DMS.

Engine Models Added and Removed From Applicability

Since we issued AD 2004-26-10, turbofan engine model Tay 611-8C received a U.S. DOT FAA type certificate. We added that engine model to the applicability, as certain serial numbers of those engines are affected by this AD.

Although AD 2004-26-10 inadvertently lists turbofan engine models Tay 620-15/20 and Tay 650-15/10 in the applicability, this proposed AD does not list them. Those engines do not have a U.S. DOT FAA type certificate.

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 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 above, I certify that the proposed AD:

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); and

3. Would 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 regulatory evaluation of the estimated costs to comply with this proposed AD. See the ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration 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 Amendment 39-13922 (70 FR 1172, January 6, 2005) and by adding the following new AD:

Rolls-Royce Deutschland (Formerly Rolls-Royce plc): Docket No. FAA-2007-27811; Directorate Identifier 2004-NE-11-AD.

Comments Due Date

(a) We must receive comments on this airworthiness directive (AD) action by September 4, 2007.

Affected ADs

(b) This AD supersedes AD 2004-26-10, Amendment 39-13922.

Applicability

(c) This AD applies to:

(1) RRD Tay 611-8, Tay 620-15, Tay 650-15, and Tay 651-54 turbofan engines that have one or more ice-impact panels installed in the low pressure (LP) compressor case that conform to the Rolls-Royce Deutschland (RRD) Service Bulletin (SB) No. TAY-72-1326 standard.

(2) RRD Tay 611-8C turbofan engines with serial numbers (SN) below SN 85078.

(3) The turbofan engines listed in paragraph (c) of this AD are installed on, but not limited to, Fokker F.28 Mk.0070 and Mk.0100 series airplanes, Gulfstream Aerospace G-IV and G-IV-X series airplanes, and Boeing Company 727-100 series airplanes modified in accordance with Supplemental Type Certificate SA8472SW (727-QF).

Unsafe Condition

(d) This AD results from RRD introducing new LP compressor case ice-impact panels with additional retention features, to these Tay turbofan engines. We are issuing this AD to prevent release of ice-impact panels due to improper bonding that can result in loss of thrust in both engines.

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.

Inspecting Ice-Impact Panels in Tay 620-15, Tay 650-15, and Tay 651-54 Engines

(f) For airplanes that have any Tay 620-15, Tay 650-15, or Tay 651-54 engines with ice-impact panels incorporated by the RR SB No. TAY-72-1326 standard, and not all panels were repaired using polysulfide bonding material by RR repair scheme TV5451R, HRS3491, HRS3615, HRS3648, or HRS3649, do the following:

(1) Before further flight, rework all six ice-impact panels using repair scheme HRS3648 or HRS3649 on at least one of the affected engines.

(2) Before further flight, inspect the ice-impact panels and the surrounding fillers on the engine not reworked. Use paragraph 3.E. of the Accomplishment Instructions of RRD SB No. TAY-72-1638, Revision 2, dated September 21, 2004, and the inspection disposition criteria in Table 1 of this AD.

Table 1.—Inspection Disposition Criteria

If:	Then:
(i) Any movement or rocking motion of LP compressor ice-impact panel, or any movement of the front edge of ice-impact panel	Before further flight, replace all panels using repair scheme HRS3648 or HRS3649.
(ii) Reappearing signs of moisture on the ice-impact panel or the surrounding filler	Before further flight, replace all panels using repair scheme HRS3648 or HRS3649.
(iii) Any dents or impact damage on the ice-impact panel that is greater than 3.1 square inch in total	Before further flight, replace the damaged panel using repair scheme HRS3648 or HRS3649.
(iv) Any dents or impact damage on the ice-impact panel that is between 1.55 square inch and 3.1 square inch in total	Within 5 flight cycles or 5 flight hours, whichever occurs first, replace the damaged panel using repair scheme HRS3648 or HRS3649.
(v) Any dents or impact damage on the ice-impact panel that is less than 1.55 square inch in total	Within 50 flight cycles or 50 flight hours, whichever occurs first, replace the damaged panel using repair scheme HRS3648 or HRS3649.
(vi) Any crack appears on the ice-impact panel and there is visible distortion of the airwashed surface	Within 50 flight cycles or 50 flight hours, whichever occurs first, replace the damaged panel using repair scheme HRS3648 or HRS3649.
(vii) Any crack appears on the ice-impact panel and there is no visible distortion of the airwashed surface	Within 150 flight cycles or 150 flight hours, whichever occurs first, replace the damaged panel using repair scheme HRS3648 or HRS3649.
(viii) Delamination or peeling of the compound layers of the airwashed surface and the penetrated area is greater than 3.1 square inch in total	Before further flight, replace the damaged panel using repair scheme HRS3648 or HRS3649.
(iv) Delamination or peeling of the compound layers of the airwashed surface and the penetrated area is between 1.55 square inch and 3.1 square inch in total	Within 5 flight cycles or 5 flight hours, whichever occurs first, replace the damaged panel using repair scheme HRS3648 or HRS3649.
(x) Delamination or peeling of the compound layers of the airwashed surface and the penetrated area is less than 1.55 square inch in total	Within 50 flight cycles or 50 flight hours, whichever occurs first, replace the damaged panel using repair scheme HRS3648 or HRS3649.
(xi) Delamination or peeling of the compound layers but the airwashed surface is not penetrated	Within 150 flight cycles or 150 flight hours, whichever occurs first, repair the damaged panel using repair scheme HRS3630.
(xii) Missing filler surrounding the LP compressor case	Before further flight, repair the damaged filler using repair scheme HRS3630.
(xiii) Damage to the filler surrounding the LP compressor case such as chipped, cracked, or missing material	Within 25 flight cycles or 25 flight hours, whichever occurs first, repair damaged filler using repair scheme HRS 3630.

(3) Re-inspect all ice-impact panels within every 500 cycles-since-last-inspection (CSLI) or two months since-last-inspection, whichever occurs first. Use paragraph 3.E. of the Accomplishment Instructions of RRD SB No. TAY-72-1638, Revision 2, dated September 21, 2004, and the inspection disposition criteria in Table 1 of this AD.

Repetitive Inspections for Tay 620-15, Tay 650-15, and Tay 651-54 Engines With All Ice-Impact Panels Repaired by Polysulfide Bonding Material

(g) For Tay 620-15, Tay 650-15, and Tay 651-54 engines with ice-impact panels incorporated by the RRD SB No. TAY-72-1326 standard, and all panels were repaired using polysulfide bonding material by RR repair scheme TV5451R, HRS3491, HRS3615, HRS3648 or HRS3649, do the following:

(1) Re-inspect within every 1,500 CSLI, for the condition of the ice-impact panels and the surrounding fillers.

(2) Use paragraph 3.E. of the Accomplishment Instructions of RRD SB No. TAY-72-1638, Revision 2, dated September 21, 2004, and the inspection disposition criteria in Table 1 of this AD.

Inspecting Ice-Impact Panels in Tay 611-8 Engines

(h) For airplanes that have any Tay 611-8 engines with ice-impact panels incorporated by the RR SB No. TAY-72-1326 standard, and RR repair scheme HRS3491 or HRS3615 was done with two pack epoxy (Omat 8/52) on one or more of the six ice-impact panels, do the following:

(1) Before further flight, rework all six ice-impact panels using repair scheme HRS3648 or HRS3649 on at least one of the affected engines.

(2) Before further flight, inspect the ice-impact panels and the surrounding fillers on the engine not reworked. Use paragraph 3.E. of the Accomplishment Instructions of RRD SB No. TAY-72-1638, Revision 2, dated September 21, 2004, and the inspection disposition criteria in Table 1 of this AD.

(3) Re-inspect the ice-impact panels within every 1,000 CSLI or six months since-last-inspection, whichever occurs first. Use paragraph 3.E. of the Accomplishment Instructions of RRD SB No. TAY-72-1639, Revision 2, dated September 21, 2004, and the inspection disposition criteria in Table 1 of this AD.

Repetitive Inspections for Tay 611-8 Engines With All Ice-Impact Panels Repaired by Polysulfide Bonding Material or Introduced Since New Production

(i) For Tay 611-8 engines with ice-impact panels incorporated by the RRD SB No. TAY-72-1326 standard and all panels were repaired using polysulfide bonding material by RR repair scheme TV5451R, HRS3491, HRS3615, HRS3648 or HRS3649, or panels were introduced since new production, do the following:

(1) Re-inspect within every 3,000 CSLI, for the condition of the ice-impact panels and the surrounding fillers.

(2) Use paragraph 3.E. of the Accomplishment Instructions of RRD SB No. TAY-72-1638, Revision 2, dated September 21, 2004, and the inspection disposition criteria in Table 1 of this AD.

Installing Tay 620-15, Tay 650-15, or Tay 651-54 Engines That Are Not Inspected

(j) After the effective date of this AD, do not install any Tay 620-15, Tay 650-15, or Tay 651-54 engines with ice-impact panels if:

(1) Those ice-impact panels incorporate the RR SB No. TAY-72-1326 standard; and

(2) Ice-impact panels were repaired using RR repair scheme TV5451R, HRS3491, or HRS3615 and bonding material other than polysulfide; unless

(3) The panels and the surrounding fillers are inspected for condition using 3.B. through 3.D.(3) (in-service) or 3.K.(1) through 3.(M)(3) (at overhaul or shop visit) of the Accomplishment Instructions of RRD SB No. TAY-72-1638, Revision 2, dated September 21, 2004.

(k) Perform repetitive inspections as specified in paragraph (g) of this AD.

Installing Tay 611-8 Engines That Are Not Inspected

(l) After the effective date of this AD, do not install any Tay 611-8 engine with ice-impact panels if:

(1) Those ice-impact panels incorporate the RR SB No. TAY-72-1326 standard; and

(2) Ice-impact panels were repaired using RR repair scheme TV5451R, HRS3491, or HRS3615 and bonding material other than polysulfide, unless

(3) The panels and the surrounding fillers are inspected for condition using 3.B. through 3.D.(2) (in-service) or 3.K.(1) through 3.M.(3) (at overhaul or shop visit) of the Accomplishment Instructions of RRD SB No. TAY-72-1639, Revision 2, dated September 21, 2004.

(m) Perform repetitive inspections as specified in paragraph (i) of this AD.

Mandatory Terminating Action

(n) No later than December 31, 2011, as mandatory terminating action to the repetitive visual inspections or rework required by paragraphs (f), (g), (h), (i), (j), (k), (l), and (m) of this AD, do the following:

(1) Rework the LP compressor case and install new LP compressor case ice-impact panels with additional retention features, at the next shop visit requiring the removal of any module, except when the work scope requires only the removal of the high speed gearbox module.

(2) For Tay 620-15, Tay 650-15, and Tay 651-54 turbofan engines, do the rework and installation using the Accomplishment Instructions of RRD Alert SB No. TAY-72-A1643, Revision 1, dated November 2, 2005.

(3) For Tay 611-8 turbofan engines, do the rework and installation using the Accomplishment Instructions of RRD Alert SB No. TAY-72-A1650, dated November 2, 2005.

Tay 611-8C Turbofan Engines

(o) For Tay 611-8C turbofan engines, no later than December 31, 2011, do the following:

(1) Rework the LP compressor case and install new LP compressor case ice-impact panels with additional retention features, at the next shop visit after the effective date of this AD, requiring the removal of any module, except when the work scope requires only the removal of the high speed gearbox module.

(2) Do the rework and installation using the Accomplishment Instructions of RRD Alert SB No. TAY-72-A1650, dated November 2, 2005.

Alternative Methods of Compliance

(p) 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.

Related Information

(q) German AD D2004-313R5, dated November 15, 2005, also addresses the subject of this AD.

(r) Contact Jason Yang, Aerospace Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; e-mail: [e-mail]; telephone [phone]; fax [phone], for more information about this AD.

Issued in Burlington, Massachusetts, on June 29, 2007.

Peter A. White,

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