E8-7302. Airworthiness Directives; Boeing Model 757-200 and 757-300 Series Airplanes

AGENCY:

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

ACTION:

Supplemental notice of proposed rulemaking (NPRM); reopening of comment period.

SUMMARY:

The FAA is revising an earlier proposed airworthiness directive (AD) for certain Boeing Model 757-200 and 757-300 series airplanes. The original NPRM would have required installing a bonding jumper between a ground and the clamp on the tube of the forward and aft gray water composite drain masts. The original NPRM resulted from a report of charred insulation blankets and burned wires around the forward gray water composite drain mast found during an inspection of the forward cargo compartment on a Model 767-300F airplane. For certain airplanes, this action revises the original NPRM by adding a new inspection of existing aft bonding jumper assemblies that might be too short, repair if necessary, and replacement of the bonding jumper assembly with a new, longer bonding jumper assembly if necessary. We are proposing this supplemental NPRM to prevent a fire near a composite drain mast and possible disruption of the electrical power system due to a lightning strike on a composite drain mast, which could result in the loss of several functions essential for safe flight.

DATES:

We must receive comments on this supplemental NPRM by May 5, 2008.

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 AD, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.

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:

Nicholas Wilson, Aerospace Engineer, Cabin Safety and Environmental Systems Branch, ANM-150S, FAA, Seattle Aircraft Certification Office, 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-2007-28160; Directorate Identifier 2007-NM-006-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 issued a notice of proposed rulemaking (NPRM) (the “original NPRM”) to amend 14 CFR part 39 to include an airworthiness directive (AD) that would apply to certain Boeing Model 757-200 and 757-300 series airplanes. The original NPRM was published in the Federal Register on May 16, 2007 (72 FR 27497). The original NPRM proposed to require installing a bonding jumper between a ground and the clamp on the tube of the forward and aft gray water composite drain masts.

Actions Since Original NPRM Was Issued

Since we issued the original NPRM, Boeing has advised us of reports of the bonding jumper being too short to reach the bracket in the aft drain installation, as described in Boeing Special Attention Service Bulletin 757-30-0024, dated July 24, 2006. Boeing has issued Special Attention Service Bulletin 757-30-0024, Revision 1, dated October 25, 2007. The procedures in this service bulletin are essentially the same as those in the original service bulletin. The service bulletin also includes procedures to correct bonding jumper assemblies that are too short on airplanes that changed the aft drain mast in accordance with the original issue of the service bulletin, and procedures that should be followed if the proper resistance values of the bonding jumper cannot be met. We have added a new paragraph to this supplemental NPRM to require inspection, repair, and replacement of the aft bonding jumper assemblies installed according to the original service bulletin that have been determined to be too short. We have also revised paragraph (f) of the supplemental NPRM to refer to Revision 1 of the service bulletin as the appropriate source of service information for the proposed requirements.

Additional Changes to This Supplemental NPRM

We have also updated the Costs of Compliance section of this supplemental NPRM to reflect the new inspection, the current number of U.S.-registered airplanes, and the cost of parts necessary to accomplish the proposed actions.

We have confirmed with the airplane manufacturer that the composite and aluminum drain mast can be interchangeable. Therefore, we have added a new paragraph (h), “Parts Installation,” to this supplemental NPRM to prohibit installation of a composite gray water drain mast, unless a bonding jumper is also installed, as specified in paragraph (f) of this AD. We have also re-identified subsequent paragraphs accordingly.

FAA's Determination and Proposed Requirements of the Supplemental NPRM

We are proposing this supplemental NPRM because we evaluated all pertinent information and determined an unsafe condition exists and is likely to exist or develop on other products of the same type design. Certain changes described above expand the scope of the original NPRM. As a result, we have determined that it is necessary to reopen the comment period to provide additional opportunity for the public to comment on this supplemental NPRM.

Costs of Compliance

There are about 83 airplanes of the affected design in the worldwide fleet. The following table provides the estimated costs for U.S. operators to comply with this supplemental NPRM.

Estimated Costs

Action	Work hours	Average labor rate per hour	Parts	Cost per airplane	Number of U.S.- registered airplanes	Fleet cost
Bonding jumper installation	2	$80	$392, per kit (1 kit per drain mast)	$944	70	$66,080.
Inspection of existing bonding jumper installation in bulk cargo compartment	1	80	$392	472	Up to 70	Up to $33,040.

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 supplemental NPRM 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
• 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 adding the following new AD:

Boeing: Docket No. FAA-2007-28160; Directorate Identifier 2007-NM-006-AD.

Comments Due Date

(a) We must receive comments by May 5, 2008.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Boeing Model 757-200 and 757-300 series airplanes, certificated in any category; as identified in Boeing Special Attention Service Bulletin 757-30-0024, Revision 1, dated October 25, 2007.

Unsafe Condition

(d) This AD results from a report of charred insulation blankets and burned wires around the forward gray water composite drain mast found during an inspection of the forward cargo compartment on a Model 767-300F airplane. We are issuing this AD to prevent a fire near a composite drain mast and possible disruption of the electrical power system due to a lightning strike on a composite drain mast, which could result in the loss of several functions essential for safe flight.

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.

Bonding Jumper Installation

(f) Except as provided by paragraph (g) of this AD: Within 60 months after the effective date of this AD, install a bonding jumper between a ground and the clamp on the tube of the forward and aft gray water composite drain mast, in accordance with Parts 1 and 2 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-30-0024, Revision 1, dated October 25, 2007.

Existing Bonding Jumper Inspection

(g) For airplanes on which the bonding jumper was installed on the aft drain mast in accordance with Boeing Special Attention Service Bulletin 757-30-0024, dated July 24, 2006: Within 60 months after the effective date of this AD, do a general visual inspection of the aft bonding jumper assembly for signs of riding (chafing) in accordance with Part 3 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-30-0024, Revision 1, dated October 25, 2007. If no riding damage is found, no further action is required by this AD for the aft drain mast. If riding damage is found, before further flight do the actions specified in paragraphs (g)(1) and (g)(2) of this AD. Doing the actions specified in this paragraph terminates the requirement to install the bonding jumper on the aft drain mast specified in paragraph (f) of this AD.

(1) Repair any riding damage found in accordance with the service bulletin.

(2) Remove the existing bonding jumper assembly and install a new, longer bonding jumper assembly in accordance with Part 3 of the Accomplishment Instructions of the service bulletin. As an option to the longer bonding jumper assembly, operators may remove the bracket, fill the holes in the stringer, and restore the finish in accordance with Part 3 of the Accomplishment Instructions of the service bulletin; and install the ground bracket and jumper assembly in accordance with Part 2 of the Accomplishment Instructions of the service bulletin.

Parts Installation

(h) As of the effective date of this AD, no person may install, on any airplane, a composite gray water drain mast, unless a bonding jumper is also installed, as specified in paragraph (f) of this AD.

Alternative Methods of Compliance (AMOCs)

(i)(1) The Manager, Seattle Aircraft Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

(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 appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.

Issued in Renton, Washington, on March 31, 2008.

Dionne Palermo,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.