2010-25255. Airworthiness Directives; The Boeing Company Model 767 Airplanes

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) that applies to certain Model 767 airplanes. The existing AD currently requires, for certain airplanes, reworking the bonding jumper assemblies on the drain tube assemblies of the slat track housing of the wings. For certain other airplanes, the existing AD requires repetitive inspections of the drain tube assemblies of the slat track housing of the wings to find discrepancies, corrective actions if necessary, and terminating action for the repetitive inspections. This proposed AD would also require replacing the drain tube assemblies. For certain airplanes, this proposed AD would also require installing an additional electrostatic bond path for the number 5 and 8 inboard slat track drain tube assemblies. For certain other airplanes, this proposed AD would also require reworking the bonding jumper assembly. This proposed AD would also revise the applicability to include additional airplanes. This proposed AD results from reports of fuel leaks from certain drain locations of the slat track housing near the engine exhaust nozzles of the wings, which could result in a fire when the airplane is stationary, or taxiing at low speed; reports of a bonding jumper assembly of certain drain tubes that did not meet bonding specifications and could result in electrostatic discharge and an in-tank ignition source; and reports of fuel leaks onto the main landing gear (MLG) as a result of a cracked drain tube at the number 5 or 8 slat track housing, which could let fuel drain from the main fuel tanks into the dry bay area of the wings and onto hot MLG brakes and result in a fire.

DATES:

We must receive comments on this proposed AD by November 22, 2010.

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: [phone].
• 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 [phone], extension 1; fax [phone]; e-mail [e-mail]; 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 [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Douglas Bryant, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone].

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-2010-0957; Directorate Identifier 2010-NM-062-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

On July 12, 2001, we issued AD 2001-14-19, amendment 39-12330 (66 FR 38350, July 24, 2001), for certain Boeing Model 767 airplanes. That AD requires, for certain airplanes, reworking the bonding jumper assemblies on the drain tube assemblies of the slat track housing of the wings. For certain other airplanes, that AD requires repetitive inspections of the drain tube assemblies of the slat track housing of the wings to find discrepancies, corrective actions if necessary, and terminating action for the repetitive inspections. That AD was prompted by reports of fuel leaks from certain drain locations of the slat track housing near the engine exhaust nozzles of the wings, which could result in a fire when the airplane is stationary or during low speed taxiing. That AD was also prompted by the discovery that the bonding jumper assembly of certain drain tube assemblies installed during production did not meet the current bonding specifications and could result in electrostatic discharge and an in-tank ignition source.

Actions Since Existing AD Was Issued

Since we issued AD 2001-14-19, we have received reports of fuel leaks onto the MLG of several airplanes due to a cracked drain tube at the number 8 slat track housing. No fires have been reported. The cracking was found on a rerouted drain tube with a flexible part. (Installing this drain tube is described in Boeing Service Bulletin 767-57A0060, and is required by AD 2001-14-19.) An investigation by Boeing revealed that the drain tubes with flexible parts cracked as a result of a high intensity engine vibration—higher than the tube's design permitted. In one case, maintenance personnel observed fuel leakage from the pylon area after the airplane had landed.

Relevant Service Information

AD 2001-14-19 refers to Boeing Service Bulletin 767-57A0060, Revision 1, dated December 31, 1998 (for Model 767-200, -300, and -300F series airplanes), as the appropriate source of service information for the repetitive inspections and terminating action. Boeing has issued Service Bulletin 767-57A0060, Revision 2, dated January 31, 2002, to include minor procedural changes. No additional work is necessary if the actions specified in Boeing Service Bulletin 767-57A0060, dated January 30, 1997; or Revision 1, dated December 31, 1998; were done.

AD 2001-14-19 refers to Boeing Service Bulletin 767-57-0068, dated September 16, 1999 (for Model 767-300 and -300F series airplanes), as the appropriate source of service information for reworking the bonding jumper assemblies. Boeing has issued Boeing Service Bulletin 767-57-0068, Revision 1, dated May 9, 2002, which corrects an error involving the original bonding jumper “A” installation sequence. Because of this error, this service bulletin specifies that additional work, including new rework procedures, is necessary.

We also have reviewed Boeing Service Bulletins 767-57A0094 (for Model 767-200, -300, and -300F series airplanes) and 767-57A0095 (for Model 767-400ER series airplanes), both Revision 2, both dated December 17, 2009. These service bulletins describe procedures for replacing drain tube assemblies that have flexible parts; the replacement assemblies have new aluminum drain tubes without flexible parts.

Boeing Service Bulletin 767-57A0094, Revision 2, dated December 17, 2009, specifies the prior or concurrent accomplishment, for certain airplanes, of Boeing Service Bulletins 767-57A0060, Revision 2, dated January 31, 2002; and 767-57-0068, Revision 1, dated May 9, 2002.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to develop on other airplanes of the same type design. For this reason, we are proposing this AD, which would supersede AD 2001-14-19 and retain the requirements of that AD. This proposed AD would also require accomplishing the new actions specified in the service information described previously, except as described below.

Difference Between Service Bulletin and Proposed AD

Boeing Service Bulletin 767-57-0068, Revision 1, dated May 9, 2002, specifies that the compliance time to rework the bonding jumper assembly (required by paragraph (l) of this NPRM) is 48 months after that date. In developing an appropriate compliance time for this action, we considered the safety implications, parts availability, and normal maintenance schedules for the timely accomplishment of the modification. We also considered that this work, if not previously accomplished as an AMOC to AD 2001-14-19, must be done concurrently with the new requirements of this proposed AD.

Changes to Existing AD

This proposed AD would revise the applicability of AD 2001-14-19 by adding line numbers 758 through 921, which were produced since that AD was issued. Those airplanes had received a production change equivalent to the actions required by the existing AD, and are now subject to the identified unsafe condition.

This proposed AD would retain the requirements of AD 2001-14-19. Since that AD was issued, the AD format has been revised, and certain paragraphs have been rearranged. As a result, the corresponding paragraph identifiers have changed in this proposed AD, as listed in the following table:

Revised Paragraph Identifiers

Requirement in AD 2001-14-19	Corresponding requirement in this proposed AD
paragraph (a)	paragraph (g)
paragraph (b)	paragraph (h)
paragraph (c)	paragraph (i)

Costs of Compliance

There are about 808 airplanes of the affected design in the worldwide fleet. The following table provides the estimated costs for U.S. operators to comply with this proposed AD. The average labor rate is $85 per hour.

Estimated Costs

Action	Work hours	Parts	Cost per airplane	Number of U.S.- registered airplanes	Fleet cost
Inspection (required by AD 2001-14-19)	1	$0	$85 per inspection cycle	255	$21,675 per inspection cycle.
Drain tube replacement (required by AD 2001-14-19)	12	5,236	$6,256	255	$1,595,280.
Bonding jumper assembly rework (required by AD 2001-14-19)	4	322	$662	47	$31,114.
Drain tube replacement (new proposed action)	Between 7 and 11, depending on configuration	1,117	Between $1,712 and $2,052	356	Between $609,472 and $730,512.
Installation of electrostatic bond path (new proposed action)	4	322	$662	47	$31,114.

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 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.

We prepared a regulatory evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket. 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
• 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.

§ 39.13

[Amended]

2. The FAA amends § 39.13 by removing amendment 39-12330 (66 FR 38350, July 24, 2001) and adding the following new AD:

The Boeing Company: Docket No. FAA-2010-0957; Directorate Identifier 2010-NM-062-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by November 22, 2010.

Affected ADs

(b) This AD supersedes AD 2001-14-19, Amendment 39-12330.

Applicability

(c) This AD applies to the airplanes, certificated in any category, identified in paragraphs (c)(1) and (c)(2) of this AD.

(1) Model 767-200, -300, and -300F series airplanes, as identified in Boeing Service Bulletin 767-57A0094, Revision 2, dated December 17, 2009.

(2) Model 767-400ER series airplanes, as identified in Boeing Service Bulletin 767-57A0095, Revision 2, dated December 17, 2009.

Subject

(d) Air Transport Association (ATA) of America Code 57: Wings.

Unsafe Condition

(e) This AD results from reports of fuel leaks from certain drain locations of the slat track housing near the engine exhaust nozzles of the wings, which could result in a fire when the airplane is stationary, or taxiing at low speed; reports of a bonding jumper assembly of certain drain tubes that did not meet bonding specifications and could result in electrostatic discharge and an in-tank ignition source; and reports of fuel leaks onto the main landing gear (MLG) as a result of a cracked drain tube at the number 5 or 8 slat track housing, which could let fuel drain from the main fuel tanks into the dry bay area of the wings and onto hot MLG brakes and result in a fire.

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.

Restatement of Requirements of AD 2001-14-19, AMENDMENT 39-12330, With Revised Service Information

Repetitive Inspections/Corrective Action

(g) For airplanes identified in Boeing Service Bulletin 767-57A0060, Revision 1, dated December 31, 1998: Within 500 flight hours after August 28, 2001 (the effective date of AD 2001-14-19), do a general visual inspection of the drain tube assemblies of the slat track housings of the wings to find discrepancies (loose fittings, cracked tubes, fuel leaks), per Part I of the Accomplishment Instructions of Boeing Service Bulletin 767-57A0060, Revision 1, dated December 31, 1998; or Revision 2, dated January 31, 2002. After the effective date of this AD, only Revision 2 may be used.

(1) If any discrepancies are found, before further flight, rework the drain tube assembly per Part II of the Accomplishment Instructions of Boeing Service Bulletin 767-57A0060, Revision 1, dated December 31, 1998; or Revision 2, dated January 31, 2002. After the effective date of this AD, only Revision 2 may be used. Repeat the inspection at intervals not to exceed 500 flight hours until accomplishment of the requirements in paragraph (h) of this AD.

(2) If no discrepancies are found, repeat the inspection thereafter at intervals not to exceed 500 flight hours, until accomplishment of the requirements in paragraph (h) of this AD.

Note 1:

For the purposes of this AD, a general visual inspection is defined as: “A visual examination of an interior or exterior area, installation, or assembly to find obvious damage, failure, or irregularity. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or drop-light and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.”

Terminating Action for Repetitive Inspections

(h) For airplanes specified in paragraph (g) of this AD: Within 6,000 flight hours or 24 months after August 28, 2001, whichever occurs first, replace the drain tube assemblies of the slat track housings of the wings (including general visual inspection and repair) per Part III of the Accomplishment Instructions of Boeing Service Bulletin 767-57A0060, Revision 1, dated December 31, 1998; or Revision 2, dated January 31, 2002. After the effective date of this AD, only Revision 2 may be used. Any applicable repair must be accomplished prior to further flight. Accomplishment of this paragraph terminates the repetitive inspections required by paragraph (g) of this AD.

Rework of Bonding Jumper Assemblies

(i) For airplanes identified in Boeing Service Bulletin 767-57-0068, dated September 16, 1999: Within 5,000 flight cycles or 22 months after August 28, 2001, whichever occurs first, rework the bonding jumper assembly of the drain tube assemblies of the slat track housing of the wings (including general visual inspection and repair) per the Accomplishment Instructions of Boeing Service Bulletin 767-57-0068, dated September 16, 1999; or Revision 1, dated May 9, 2002. After the effective date of this AD, only Revision 1 may be used. Any applicable repair must be accomplished prior to further flight.

New Requirements of this AD

Drain Tube Replacement

(j) Within 24 months after the effective date of this AD, replace affected drain tube assemblies of the number 5 and number 8 inboard slat track housing, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 767-57A0094 (for Model 767-200, -300, and -300F series airplanes) or 767-57A0095 (for Model 767-400ER series airplanes), both Revision 2, both dated December 17, 2009.

Concurrent Requirements

(k) For airplanes in Groups 1, 2, and 3, as identified in Boeing Service Bulletin 767-57A0094, Revision 2, dated December 17, 2009: The actions specified in paragraphs (k)(1), (k)(2), and (k)(3) of this AD, as applicable, must be done before or concurrently with the requirements of paragraph (j) of this AD.

(1) For Groups 1 and 2: The requirements of paragraph (h) of this AD.

(2) For Group 2 airplanes: Installation of an additional electrostatic bond path for the number 5 and 8 inboard slat track drain tube assemblies, in accordance with Part IV of the Accomplishment Instructions of Boeing Service Bulletin 767-57A0060, Revision 1, dated December 31, 1998; or Revision 2, dated January 31, 2002.

(3) For Group 3 airplanes: The requirements of paragraph (i) of this AD.

(l) For airplanes identified in paragraph (i) of this AD, on which the actions required by paragraph (i) of this AD were done before the effective date of this AD in accordance with Boeing Service Bulletin 767-57-0068, dated September 16, 1999: Prior to or concurrently with the requirements of paragraph (j) of this AD, rework the bonding jumper assembly for the number 5 and 8 inboard slat track housing drain tube installation, in accordance with Part 2 of the Accomplishment Instructions of Boeing Service Bulletin 767-57-0068, Revision 1, dated May 9, 2002.

Credit for Actions Accomplished in Accordance With Previous Service Information

(m) Actions done before the effective date of this AD in accordance with an applicable service bulletin identified in Table 1 of this AD are acceptable for compliance with the corresponding requirements of paragraph (j) of this AD.

Table 1—Credit Service Bulletins

Affected airplanes	Service Bulletin	Revision level	Date
Model 767-200, -300, and -300F series airplanes	Boeing Service Bulletin 767-57A0094	Original 1	June 2, 2005. December 19, 2006.
Model 767-400ER series airplanes	Boeing Service Bulletin 767-57A0095	Original 1	June 2, 2005. December 19, 2006.

Alternative Methods of Compliance (AMOCs)

(n)(1) The Manager, Seattle Aircraft Certification Office (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: Douglas Bryant, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle ACO, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone]. Information may be e-mailed to [e-mail].

(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically refer to this AD.

(3) AMOCs approved previously in accordance with AD 2001-14-19, Amendment 39-12330, are approved as AMOCs for the corresponding provisions of this AD.

Issued in Renton, Washington, on October 1, 2010.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.