Airworthiness directives: Boeing,

[Federal Register: September 2, 1998 (Volume 63, Number 170)]

[Rules and Regulations]

[Page 46647-46648]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr02se98-10]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-242-AD; Amendment 39-10730; AD 98-18-14]

RIN 2120-AA64

Airworthiness Directives; Boeing Model 757-200 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

SUMMARY: This amendment adopts a new airworthiness directive (AD) that is applicable to certain Boeing Model 757-200 series airplanes. This action requires a one-time detailed visual inspection to detect damage or chafing of certain electrical wire bundles, and to verify adequate clearance exists between the wire bundles and adjacent disconnect bracket; and repair, if necessary. This amendment is prompted by a report indicating that damaged wires caused an electrical short in the electrical panel, which resulted in a shower of sparks from the overhead panel. The actions specified in this AD are intended to prevent failure of essential electrical systems and a potential fire hazard for passengers and crewmembers, due to damage or chafing of electrical wire bundles.

DATES: Effective September 17, 1998.

Comments for inclusion in the Rules Docket must be received on or before November 2, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-242-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Information pertaining to this amendment may be obtained from or examined at the FAA, Transport Airplane Directorate, 1601 Lind Ave, SW., Renton, Washington 98055-4056.

FOR FURTHER INFORMATION CONTACT: Forrest Keller, Senior Engineer, Systems and Equipment Branch, ANM-130S, FAA, Transport Airplane Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2790; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION: The FAA has received a report indicating that damaged wires caused an electrical short in the P11 electrical panel on a Boeing Model 757-200 series airplane after takeoff, which resulted in a shower of sparks from the overhead panel. Subsequently, several erroneous flight deck indications appeared with the display of multiple caution messages by the engine indication and crew alerting system (EICAS). Investigation of the looms behind the P11 electrical panel revealed that certain wires were routed over the top of the disconnect bracket close to the bracket-bonding stud, which caused the wires to chafe through and resulted in an electrical short in the panel. In a fleetwide inspection of 13 other Boeing Model 757-200 series airplanes, damaged wires on three additional airplanes were detected. This condition, if not corrected, could result in failure of essential electrical systems and a potential fire hazard for passengers and crewmembers, due to damage or chafing of electrical wire bundles.

Explanation of the Requirements of the Rule

Since an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design, this AD is being issued to prevent failure of essential electrical systems and a potential fire hazard for passengers and crewmembers, due to damage or chafing of electrical wire bundles. This AD requires a one-time detailed visual inspection to detect damage or chafing of certain electrical wire bundles, and to verify adequate clearance exists between the wire bundles and adjacent disconnect bracket; and repair, if necessary. Accomplishment of the actions described previously is intended to adequately address the identified unsafe condition.

Determination of Rule's Effective Date

Since a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days.

Comments Invited

Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified under the caption ADDRESSES. All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filedin the Rules Docket.

[[Page 46648]]

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: ``Comments to Docket Number 98-NM-242-AD.'' The postcard will be date stamped and returned to the commenter.

Regulatory Impact

The regulations adopted herein will not have substantial direct effects 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. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and that it is not a ``significant regulatory action'' under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new airworthiness directive: 98-18-14 Boeing: Amendment 39-10730. Docket 98-NM-242-AD.

   Applicability: Model 757-200 series airplanes, certificated in any category; excluding the following line numbers:

   2 75 221 127 130 162 180 209 212 219 388 526

   Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

   Compliance: Required as indicated, unless accomplished previously.

   To prevent failure of essential electrical systems and a potential fire hazard for passengers and crewmembers due to damage or chafing of electrical wire bundles, accomplish the following:

   (a) Within 90 days after the effective date of this AD, perform a one-time detailed visual inspection to detect damage or chafing of the electrical wire bundles having part numbers W2016-0001-12 and W2016-0002-16, and adjacent wiring; and to verify adequate clearance exists between the wire bundles and adjacent disconnect bracket. Pay particular attention to the area located on the looms behind the P11 panel near the AP0011 disconnect bracket.

   (1) If no damage or chafing is detected, and adequate clearance exists, no further action is required by this AD.

   (2) If damage or chafing is detected, and adequate clearance exists, prior to further flight, repair the wire bundles in accordance with Section 20-10-13 of the Boeing Standard Wiring Practices Manual.

   (3) If no damage or chafing is detected and inadequate clearance exists, prior to further flight, modify the wire bundles to achieve adequate clearance, in accordance with Section 20-10-11 and 20-10-12 of the Boeing Standard Wiring Practices Manual.

   (4) If damage or chafing is detected and inadequate clearance exists, prior to further flight, repair the wire bundles in accordance with Section 20-10-13 of the Boeing Standard Wiring Practices Manual; and modify the wire bundles in accordance with Section 20-10-11 and 20-10-12 of the Boeing Standard Wiring Practices Manual.

   (b) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO.

   Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.

   (c) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

   (d) This amendment becomes effective on September 17, 1998.

   Issued in Renton, Washington, on August 27, 1998. Vi L. Lipski, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

   [FR Doc. 98-23620Filed9-1-98; 8:45 am]

   BILLING CODE 4910-13-U