Airworthiness Directives:
Federal Register: January 20, 2011 (Volume 76, Number 13)
Proposed Rules
Page 3561-3564
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
DOCID:fr20ja11-17
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration 14 CFR Part 39
Docket No. FAA-2011-0027; Directorate Identifier 2010-NM-127-AD
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Model 777-200 and - 300 Series Airplanes Equipped with Rolls-Royce RB211 Trent 800 Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
SUMMARY: We propose to adopt a new airworthiness directive (AD) for certain Model 777-200 and -300 series airplanes. This proposed AD would require repetitive inspections of all thrust reverser (T/R) structure and sealant for degradation, and related investigative and corrective actions if necessary. This proposed AD results from reports of thrust reverser events related to thermal damage of the thrust reverser inner wall. We are proposing this AD to detect and correct a degraded T/R inner wall panel, which could lead to failure of a T/R and adjacent components and their consequent separation from the airplane, which could result in a rejected takeoff (RTO) and cause asymmetric thrust and consequent loss of control of the airplane during reverse thrust operation. If a T/R inner wall overheats, separated components could cause structural damage to the airplane, damage to other airplanes, or possible injury to people on the ground.
DATES: We must receive comments on this proposed AD by March 7, 2011.
ADDRESSES: You may send comments by any of the following methods:
Federal eRulemaking Portal: Go to http:// www.regulations.gov. Follow the instructions for submitting comments.
Fax: 202-493-2251.
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: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.
For service information identified in this proposed AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206- 544-5000, extension 1; fax 206-766-5680; e-mail me.boecom@boeing.com;
Internet https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane
Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.
Examining the AD Docket
You may examine the AD docket on the Internet at http:// www.regulations.gov; or in person at the Docket Management Facility 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 Office (telephone 800-647-5527) is in the
ADDRESSES section. Comments will be available in the AD docket shortly after receipt.
FOR FURTHER INFORMATION CONTACT: Margaret Langsted, Aerospace Engineer,
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification
Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone
(425) 917-6500; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include ``Docket No. FAA-2011-0027;
Directorate Identifier 2010-NM-127-AD'' at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments.
We will post all comments we receive, without change, to http:// www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.
Discussion
We have received reports of eleven events related to thermal damage of the thrust reverser (T/R) inner wall on Rolls Royce RB211 Trent 800 engines. The events have included air turnbacks, in-flight shutdowns,
T/R inner wall panel sections and parts being separated from the airplane, collapse of the T/R inner wall panel, and engine fire loop fault messages. No hull loss or personal injury has occurred from these events. Boeing issued Alert Service Bulletin 777-78A0059, dated
February 24, 2005; and Alert Service Bulletin 777-78-0060, dated
February 24, 2005; to provide instructions for inspecting the T/R inner wall panel structure and sealing the insulation blankets to prevent hot under-cowl air from contact with the T/R inner wall panel. Since those service bulletins were released, there have been seven events on thrust reversers, four T/Rs on which those service bulletins had not been fully accomplished, and three on which those service bulletins had been fully accomplished. A separated T/R piece could result in a rejected takeoff and cause asymmetric thrust and consequent loss of control of the airplane during reverse thrust operation. If a thrust reverser inner wall overheats, separated components could cause structural damage to the airplane, damage to other airplanes, or injury to people on the ground.
Relevant Service Information
We have reviewed Boeing Alert Service Bulletin 777-78A0065,
Revision 2, dated May 6, 2010. This service bulletin describes procedures for doing actions specified in Work Packages 1 through 6 (as necessary) of the
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Accomplishment Instructions. This service bulletin states that operators may choose between doing Work Package 2 (doing a full non- destructive test (NDT)), or Work Package 6 (doing a limited NDT with more restrictive repetitive intervals).
Work Package 1
Boeing Alert Service Bulletin 777-78A0065, Revision 2, dated May 6, 2010, describes procedures for reviewing the airplane maintenance records to determine whether sealant was added; repetitive detailed inspections of all thrust reverser (T/R) inner wall insulation blanket edges, grommet holes, penetrations, and seams for sealant that is cracked, has gaps, is loose, or is missing; repetitive general visual inspections of click bond studs, blanket studs, and temporary fasteners; replacement of sealant if necessary; and related investigative and corrective actions if necessary. The related investigative actions include:
Measuring the distance between the overlapped blanket face sheets adjacent to the damaged or missing sealant, or measuring the distance between the inner wall and the insulation blanket adjacent to the damaged or missing sealant
Doing an NDT and general visual inspection for thermal degradation of the exposed T/R inner wall panel area within 12 inches of cracks, gaps, or loose or missing sealant
Doing an NDT of an uncovered compression pad if it is within 12 inches of the crack, gap, loose, or missing sealant
Doing a general visual inspection for areas of thermal degradation
Doing an NDT of the T/R inner wall panel where the fitting was installed
Doing a detailed inspection of the T/R panel wall inner bolt holes for elongation
Doing a general visual inspection and NDT inspection for thermal degradation of the inner wall panel area where a damaged click bond stud, blanket stud, and temporary fastener is loose, damaged, or missing
Doing an NDT (eddy current conductivity test) of the number 1 upper, or numbers 1 and 2 lower, compression pad fittings if they are exposed by blanket removal and within 12 inches of the loose, damaged, or missing click bond studs, blanket studs, or temporary fasteners
Doing a Barcol hardness test of the area of thermal degradation
Doing a general visual inspection of bushings for migration or looseness
The corrective actions include:
Replacing damaged or missing sealant
Repairing or replacing T/R inner wall panel areas
Contacting Boeing for repair instructions and doing the repair
Installing compression pad fittings
Installing replacement click bonds, blanket studs, or temporary fasteners
Installing the removed replacement blankets and fittings
Removing the bushing and repairing the inner wall panel bolt hole
Work Package 2
Boeing Alert Service Bulletin 777-78A0065, Revision 2, dated May 6, 2010, describes procedures for either a repetitive full inner wall panel NDT of each T/R half and repetitive general visual inspections for areas of thermal degradation, or a partial inner wall panel NDT, and related investigative and corrective actions. The related investigative actions include an NDT of the area of different color, and a Barcol hardness inspection of the inner wall panel for areas of thermal degradation. The corrective actions are repairing or replacing unsatisfactory T/R inner wall panel areas, installing insulation blankets, and contacting Boeing for repair instructions and doing the repair. This service bulletin states that Work Package 6 may be done as an alternative to Work Package 2, provided that the shorter interval for the repetitive inspections specified in Work Package 6 are followed.
Work Package 3
Boeing Alert Service Bulletin 777-78A0065, Revision 2, dated May 6, 2010, describes procedures for repetitive detailed inspections of the powered door opening system (PDOS) lug bushings on the upper number 1 compression pad fittings for hole elongation, deformation, and contact with the PDOS actuator, and related investigative and corrective actions. Related investigative actions include a detailed inspection of the PDOS lug. Corrective actions include replacing unserviceable upper number 1 compression pad fittings and replacing unserviceable bushings with serviceable parts, and installing PDOS actuator rods and sealant.
Work Package 4
Boeing Alert Service Bulletin 777-78A0065, Revision 2, dated May 6, 2010, describes procedures for repetitive NDTs of the number 1 upper and numbers 1 and 2 lower compression pad fittings, and related investigative and corrective actions. The related investigative actions include doing an NDT of the T/R inner wall panel, a general visual inspection for areas of thermal degradation, a detailed inspection of the T/R inner wall panel bolt holes for elongation, a Barcol hardness test of the area, and a general visual inspection of the bushing for migration or looseness. Corrective actions include repairing the T/R inner wall panel with a serviceable panel, installing removed installation blankets, installing serviceable compression pad fittings, contacting Boeing for repair instructions and doing the repair, replacing the T/R inner wall panel with a new or serviceable T/R inner wall panel, and removing bushings and repairing the inner wall panel bolt hole.
Work Package 5
Boeing Alert Service Bulletin 777-78A0065, Revision 2, dated May 6, 2010, describes procedures for repetitive general visual inspections of the perforated side of the T/R wall aft of the intermediate pressure compressor 8th stage (IP8) duct and high pressure compressor 3rd stage
(HP3) bleed port exits for a color that is different from that of the general area, and related investigative and corrective actions. The related investigative action is an NDT inspection of discolored areas for delamination and disbonding on the perforated side of the inner wall. The corrective actions are contacting Boeing for repair instructions and doing the repair.
Work Package 6
Boeing Alert Service Bulletin 777-78A0065, Revision 2, dated May 6, 2010, describes procedures for a limited area NDT inspection of the inner wall panel of each T/R half for delaminating and disbonding, a general visual inspection for areas of thermal degradation, and related investigative and corrective actions. Related investigative actions include a Barcol hardness test of the area. Corrective actions include repairing or replacing the T/R inner wall panel with a new or serviceable one. Work Package 6 may be done as an option to Work
Package 2 provided that the shorter repeat inspection intervals specified in Work Package 2 are followed.
Compliance Times
The compliance times for Work Package 1 are as follows. The compliance time for the initial inspections and replacement of sealant
(if necessary) is within 1,500 flight hours after the date on the original issue of the service bulletin. The interval for the repetitive inspections is 1,500 flight hours.
Page 3563
The compliance times for doing the initial and repetitive NDT inspections on the T/R wall depend on which work packages are done-- either the full NDT option (Work Packages 2 and 5) or limited NDT option (Work Packages 5 and 6). For the initial full NDT and limited
NDT options, the compliance time is between 600 and 2,000 flight cycles, depending on the number of total airplane flight cycles and whether a previous inspection has been conducted. The interval for the repetitive inspections for the full NDT is 2,000 flight cycles. The interval for the repetitive inspections for the limited NDT is 700 flight cycles.
The compliance times for Work Package 3 are as follows. The compliance time for the detailed inspection of the PDOS lug bushings on the upper number 1 compression pad fittings ranges from within 600 to 1,700 flight cycles after the date on the original issue of the service bulletin. The interval for the repetitive inspections is 2,000 flight cycles.
The compliance times for Work Package 4 are as follows. The compliance time for the initial NDT inspection of the number 1 upper, and number 1 and 2 lower, compression pad fittings are within 2,000 flight cycles after the date on the original issue of this service bulletin. The interval for the repetitive inspections is 2,000 flight cycles.
FAA's Determination and Requirements of This Proposed AD
We are proposing this AD because we evaluated all relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.
This proposed AD would require accomplishing the actions specified in the service information described previously, except as discussed under
``Differences Between the Proposed AD and Service Information.''
Differences Between the Proposed AD and Service Information
Although Boeing Alert Service Bulletin 777-78A0065, Revision 2, dated May 6, 2010, specifies that operators may contact the manufacturer for disposition of certain repair conditions, this proposed AD would require operators to repair those conditions using a method approved by the FAA.
Interim Action
We consider this proposed AD interim action. The manufacturer is currently developing a modification that will address the unsafe condition identified in this AD. Once this modification is developed, approved, and available, we might consider additional rulemaking.
Costs of Compliance
We estimate that this proposed AD would affect 54 airplanes of U.S. registry. The following table provides the estimated costs for U.S. operators to comply with this proposed AD.
Table--Estimated costs
Number of U.S.-
Action
Work hours
Average labor
Cost per
registered
Fleet cost rate per hour
product
airplanes
Records check...................
1
$85
$85
54
$4,590
Inspections.....................
73
85
6,205
54
335,070
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 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 this proposed regulation: 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. 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.
You can find our regulatory evaluation and the estimated costs of compliance in the AD Docket.
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 39--AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended] 2. The FAA amends Sec. 39.13 by adding the following new AD:
The Boeing Company: Docket No. FAA-2011-0027; Directorate Identifier 2010-NM-127-AD.
Comments Due Date
(a) We must receive comments by March 7, 2011.
Affected ADs
(b) None.
Applicability
(c) This AD applies to The Boeing Company Model 777-200 and -300 series airplanes, certificated in any category, equipped with Rolls-
Royce RB211 Trent 800
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engines; as identified in Boeing Alert Service Bulletin 777-78A0065,
Revision 2, dated May 6, 2010.
Subject
(d) Air Transport Association (ATA) of America Code 78: Engine exhaust.
Unsafe Condition
(e) This AD results from reports of thrust reverser events related to thermal damage of the thrust reverser (T/R) inner wall.
The Federal Aviation Administration is issuing this AD to detect and correct a degraded T/R inner wall panel, which could lead to failure of a T/R and adjacent components and their consequent separation from the airplane, which could result in a rejected takeoff (RTO) and cause asymmetric thrust and consequent loss of control of the airplane during reverse thrust operation. If a T/R inner wall overheats, separated components could cause structural damage to the airplane, damage to other airplanes, or possible injury to people on the ground.
Compliance
(f) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the actions have already been done.
Records Review, Inspections, and Related Investigative and Corrective
Actions
(g) Except as required by paragraphs (h), (i), (j), and (k) of this AD, at the applicable times in paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 777-78A0065, Revision 2, dated May 6, 2010 (``this service bulletin''), review the airplane maintenance records to determine whether sealant was added, do the actions specified in paragraphs (g)(1), (g)(2), (g)(3), (g)(4), and (g)(5) of this AD, and do all applicable related investigative and corrective actions, in accordance with the Accomplishment
Instructions of this service bulletin, except as required by paragraph (l) of this AD. Do all applicable related investigative and corrective actions before further flight. Repeat the inspections required by paragraphs (g)(1), (g)(2), (g)(3), (g)(4), and (g)(5) of this AD thereafter at the applicable intervals specified in paragraph 1.E., ``Compliance,'' of the service bulletin.
(1) Do a detailed inspection of all T/R inner wall insulation blanket edges, grommet holes, penetrations, and seams for sealant that is cracked, has gaps, is loose, or is missing; do a general visual inspection of click bond studs, blanket studs, and temporary fasteners; and replace sealant as applicable; in accordance with
Work Package 1 of the Accomplishment Instructions of this service bulletin.
(2) Do the actions required by paragraph (g)(2)(i) or (g)(2)(ii) of this AD.
(i) Do a full inner wall panel non-destructive test (NDT) for delamination and disbonding of each T/R half, and do a general visual inspection for areas of thermal degradation, in accordance with Work Package 2 of the Accomplishment Instructions of this service bulletin.
(ii) Do a limited area NDT of the inner wall panel of each T/R half for delamination and disbonding, and do a general visual inspection for areas of thermal degradation, in accordance with Work
Package 6 of the Accomplishment Instructions of this service bulletin.
(3) Do a general visual inspection of the T/R perforated wall aft of the intermediate pressure compressor 8th stage (IP8) and the high pressure compressor 3rd stage (HP3) bleed port exits for a color that is different from that of the general area, in accordance with Work Package 5 of the Accomplishment Instructions of this service bulletin.
(4) Do a detailed inspection of the powered door opening system
(PDOS) lug bushings on the upper number 1 compression pad fittings for hole elongation, deformation, and contact with the PDOS actuator, in accordance with Work Package 3 of the Accomplishment
Instructions of this service bulletin.
(5) Do an NDT of the number 1 upper and numbers 1 and 2 lower compression pad fittings, in accordance with Work Package 4 of the
Accomplishment Instructions of this service bulletin.
Exceptions to the Service Bulletin
(h) Where Boeing Alert Service Bulletin 777-78A0065, Revision 2, dated May 6, 2010, specifies a compliance time after the date on the original issue of that service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD.
(i) Where paragraph 1.E., ``Compliance,'' in Boeing Alert
Service Bulletin 777-78A0065, Revision 2, dated May 6, 2010, specifies a compliance time of ``2,000 flight cycles after the date of the operator's own inspections,'' for doing Work Packages 2 and 5, or Work Packages 2 and 6, this AD requires compliance within 2,000 flight cycles after the date of the operator's own inspections or within 12 months after the effective date of this AD, whichever occurs later.
(j) Where the Condition columns in Table 2 of paragraph 1.E.,
``Compliance,'' of Boeing Alert Service Bulletin 777-78A0065,
Revision 2, dated May 6, 2010, refer to ``All airplanes, each T/R half'' that has or has not ``been inspected before the date on this service bulletin,'' this AD applies to all airplanes, each T/R half that has or has not been inspected before the effective date of this
AD.
(k) Where the Condition columns in the Tables of paragraph 1.E.,
``Compliance,'' of Boeing Alert Service Bulletin 777-78A0065,
Revision 2, dated May 6, 2010, refer to total flight cycles, this AD applies to the airplanes with the specified total flight cycles as of the effective date of this AD.
(l) Where Boeing Alert Service Bulletin 777-78A0065, Revision 2, dated May 6, 2010, specifies to contact Boeing for appropriate action: Before further flight, repair in accordance with a method approved by the Manager, Seattle Aircraft Certification Office
(ACO), FAA. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD.
Credit for Actions Accomplished in Accordance With Previous Service
Information
(m) Actions done before the effective date of this AD in accordance with Boeing Alert Service Bulletin 777-78A0065, dated
June 23, 2008; or Revision 1, dated January 29, 2009; are acceptable for compliance with the corresponding requirements of this AD.
Alternative Methods of Compliance (AMOCs)
(n)(1) The Manager, Seattle ACO, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to Attn: Margaret Langsted,
Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton,
Washington 98057-3356; telephone (425) 917-6500; fax (425) 917-6590.
Or, e-mail information to 9-ANM-Seattle-ACO-AMOC-Requests@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.
Issued in Renton, Washington, on January 12, 2011.
Jeffrey E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
FR Doc. 2011-1121 Filed 1-19-11; 8:45 am
BILLING CODE 4910-13-P
