E6-1683. Airworthiness Directives; Bombardier Model DHC-8-102, -103, and -106 Airplanes; and Model DHC-8-200 and -300 Series Airplanes

AGENCY:

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

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to revise an existing airworthiness directive (AD) that applies to certain Bombardier Model DHC-8-102, -103, and -106 airplanes; and Model DHC-8-200 and -300 series airplanes. The existing AD currently requires performing a one-time inspection to detect chafing of electrical wires in the cable trough below the cabin floor; repairing, if necessary; installing additional tie-mounts and tie-wraps; applying sealant to rivet heads; and modifying electrical wires in certain sections. This proposed AD would, for certain airplanes, eliminate the requirement to modify electrical wires in certain sections. This proposed AD results from a report indicating that the modification of electrical wires does not need to be done on certain airplanes subject to the existing AD. We are proposing this AD to prevent chafing of electrical wires, which could result in an uncommanded shutdown of an engine during flight.

DATES:

We must receive comments on this proposed AD by March 10, 2006.

ADDRESSES:

Use one of the following addresses to submit comments 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: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street SW., Nassif Building, Room PL-401, Washington, DC 20590.
• Fax: [phone].
• Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Contact Bombardier, Inc., Bombardier Regional Aircraft Division, 123 Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada, for service information identified in this proposed AD.

FOR FURTHER INFORMATION CONTACT:

Douglas G. Wagner, Aerospace Engineer, Systems and Flight Test Branch, ANE-172, New York Aircraft Certification Office, FAA, 1600 Stewart Avenue, Suite 410, Westbury, New York 11590; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any relevant written data, views, or arguments regarding this proposed AD. Send your comments to an address listed in the ADDRESSES section. Include the docket number “Docket No. FAA-2006-23820; Directorate Identifier 2005-NM-249-AD” at the beginning 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 that Web site, anyone can find and read the comments in a docket, 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 Docket

You may examine the AD docket on the Internet at http://dms.dot.gov,, or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone [phone]) is located on the plaza level of the Nassif Building at the DOT street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after the Docket Management System receives them.

Discussion

On January 29, 2004, we issued AD 2004-03-15, amendment 39-13459 (69 FR 7111, February 13, 2004), for certain Bombardier Model DHC-8-102, -103, -106, -201, -202, -301, -311, and -315 airplanes. That AD requires a one-time inspection to detect chafing of electrical wires in the cable trough below the cabin floor; repair, if necessary; installation of additional tie-mounts and tie-wraps; application of sealant to rivet heads; and modification of the electrical wires in certain sections. That AD resulted from a report of an uncommanded engine shutdown during flight. We issued that AD to prevent chafing of electrical wires, which could result in an uncommanded shutdown of an engine during flight.

Actions Since Existing AD Was Issued

Paragraph (b) of AD 2004-03-15 requires all airplanes subject to the AD to modify the electrical wires in the cable trough below the cabin floor at Sections X510.00 to X580.50, in accordance with Bombardier Service Bulletin 8-53-80, Revision ‘A,’ dated July 25, 2000. Since we issued AD 2004-03-15, we have received a report indicating that Bombardier Model DHC-8-300 series airplanes should not be required to do this modification.

We have reviewed Canadian airworthiness directive CF-1998-08R2, dated July 12, 2000, which AD 2004-03-15 refers to as the parallel Canadian airworthiness directive. Canadian airworthiness directive CF-1998-08R2 identifies Model DHC-8-300 series airplanes as being subject only to Bombardier Service Bulletin S.B. 8-53-66, dated March 27, 1998, not to Bombardier Service Bulletin 8-53-80, Revision ‘A.’ (Paragraph (a) of AD 2004-03-15 refers to Bombardier Service Bulletin S.B. 8-53-66 as the appropriate source of service information for the actions required by that paragraph.)

FAA's Determination and Requirements of the Proposed AD

These airplane models are manufactured in Canada 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. Pursuant to this bilateral airworthiness agreement, Transport Canada Civil Aviation (TCCA), which is the airworthiness authority for Canada, has kept the FAA informed of the situation described above. We have examined TCCA's findings, evaluated all pertinent information, and determined that we need to issue an AD for airplanes of this type design that are certificated for operation in the United States.

This proposed AD would revise AD 2004-03-15 and would retain the requirements of the existing AD. This proposed AD would eliminate the requirement to modify electrical wires in certain sections on Model DHC-8-300 series airplanes. The actions would be required to be done in accordance with the service information specified in the existing AD, except as discussed under “Difference Between This Proposed AD and Service Bulletin” in the notice of proposed rulemaking for AD 2004-03-15.

Changes to Existing AD

This proposed AD would retain all requirements of AD 2004-03-15. Since AD 2004-03-15 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 2004-03-15	Corresponding requirement in this proposed AD
paragraph (a)	paragraph (f).
paragraph (b)	paragraph (g).

Also, we have revised the range of airplane serial numbers (S/Ns) stated in paragraphs (f)(1) and (f)(2) of this proposed AD. Paragraphs (a)(1) and (a)(2) of AD 2004-03-15 specify the compliance times for inspections in accordance with Bombardier Service Bulletin 8-53-66, as required by paragraph (a) of that AD. Paragraph (a)(1) of AD 2004-03-15 states the compliance time for S/Ns 3 through 519 inclusive (excluding S/N 462). Paragraph (a)(2) states the compliance time for S/Ns 520 through 540 inclusive. We have determined that the airplane having S/N 519 was incorrectly included in paragraph (a)(1) of AD 2004-03-15. That airplane is a Model DHC-8-300 series airplane and should be subject to the compliance time in paragraph (a)(2) of AD 2004-03-15. Therefore, we have revised paragraphs (f)(1) and (f)(2) of this proposed AD to move S/N 519 into paragraph (f)(2) of this proposed AD. (This change results in a slight extension of the compliance time for the airplane having S/N 519.)

Clarification of Alternative Method of Compliance (AMOC) Paragraph

We have revised this action to clarify the appropriate procedure for notifying the principal inspector before using any approved AMOC on any airplane to which the AMOC applies.

Costs of Compliance

This new AD adds no new costs to affected operators; in fact, it reduces the costs for some airplanes that are not subject to the modification of certain wiring.

We estimate that 173 airplanes of U.S. registry will be subject to the inspection, installation of additional tie-mounts and tie-wraps, and application of sealant to rivet heads that are currently required by AD 2004-03-15. These actions take between 80 and 100 work hours per airplane, at an average labor rate of $65 per work hour. Required parts are provided by the manufacturer at no cost to the operator. Based on these figures, the estimated cost of these actions on U.S. operators is between $899,600 and $1,124,500, or between $5,200 and $6,500 per airplane.

We estimate that 103 airplanes of U.S. registry are subject to the modification of certain wiring that is currently required by AD 2004-03-15. This action takes approximately 10 work hours per airplane, at an average labor rate of $65 per work hour. Required parts are provided by the manufacturer at no cost to the operator. Based on these figures, the estimated cost of the modification on U.S. operators is $66,950, or $650 per airplane.

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
• 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 Federal Aviation Administration (FAA) amends § 39.13 by removing amendment 39-13459 (69 FR 7111, February 13, 2004) and adding the following new airworthiness directive (AD):

Bombardier, Inc. (Formerly de Havilland, Inc.): Docket No. FAA-2006-23820; Directorate Identifier 2005-NM-249-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by March 10, 2006.

Affected ADs

(b) This AD revises AD 2004-03-15.

Applicability

(c) This AD applies to Bombardier Model DHC-8-102, -103, and -106 airplanes; and Model DHC-8-200 and DHC-8-300 series airplanes; certificated in any category serial numbers 3 through 540 inclusive, excluding serial number 462.

Unsafe Condition

(d) This AD results from a report indicating that the modification of electrical wires does not need to be done on certain airplanes subject to the existing AD. We are issuing this AD to prevent chafing of electrical wires, which could result in an uncommanded shutdown of an engine during 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.

Requirements of AD 2004-03-15

One-Time Inspection, Corrective Action, and Modification

(f) Perform a one-time general visual inspection to detect chafing of electrical wires in the cable trough below the cabin floor; install additional tie-mounts and tie-wraps; and apply sealant to rivet heads (reference Bombardier Modification 8/2705); in accordance with Bombardier Service Bulletin S.B. 8-53-66, dated March 27, 1998, at the time specified in paragraph (f)(1) or (f)(2) of this AD, as applicable. If any chafing is detected during the inspection required by this paragraph, prior to further flight, repair in accordance with the service bulletin.

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 detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to enhance visual access to all exposed surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight 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.”

(1) For airplanes having serial numbers 3 through 518 inclusive, excluding serial number 462: Inspect within 36 months after October 27, 1998 (the effective date of AD 98-20-14, amendment 39-10781).

(2) For airplanes having serial numbers 519 through 540 inclusive: Inspect within 36 months after November 10, 1999 (the effective date of AD 99-21-09, amendment 39-11352, which superseded AD 98-20-14), or at the next “C” check, whichever occurs first.

Modification

(g) For Model DHC-8-102, -103, and -106 airplanes; and Model DHC-8-200 series airplanes: Within 36 months after March 19, 2004 (the effective date of AD 2004-03-15), modify the electrical wires in the cable trough below the cabin floor at Sections X510.00 to X580.50 (including performing a general visual inspection and any applicable repair), in accordance with Part III, paragraphs 1 through 9 and 12 through 20, of the Accomplishment Instructions of Bombardier Service Bulletin 8-53-80, Revision “A,” dated July 25, 2000. Any applicable repair must be done before further flight. Accomplishment of these actions before March 19, 2004, in accordance with Bombardier Service Bulletin 8-53-80, dated December 22, 1999, is considered acceptable for compliance with the actions required by this paragraph.

Alternative Methods of Compliance (AMOCs)

(h)(1) The Manager, New York 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) Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.

Related Information

(i) Canadian airworthiness directive CF-1998-08R2, dated July 10, 2000, also addresses the subject of this AD.

Issued in Renton, Washington, on January 30, 2006.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.