E6-20969. Airworthiness Directives; Bombardier Model DHC-8-102, -103, and -106 Airplanes; and Model DHC-8-200 and DHC-8-300 Series Airplanes

AGENCY:

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

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for certain Bombardier Model DHC-8-100 (as described above), DHC-8-200, and DHC-8-300 series airplanes. This proposed AD would require doing a one-time inspection for damage of the electrical cable harness assembly located on the left and right wing root to fuselage aft seal, and repair if necessary; and reworking the fuselage aft seal assembly (left and right) to create a clearance between the electrical cable assemblies and the edge of the fairing panel. This proposed AD results from a report that an airplane encountered an uncommanded propeller feathering during climb, which resulted in an emergency landing. We are proposing this AD to prevent chafing or grounding of the wiring against the aft seal assemblies, which, if not corrected, could interrupt the operation of various systems, including the propeller feather control, alternating current (AC) electrical power, and standby hydraulic power, and result in reduced controllability of the airplane.

DATES:

We must receive comments on this proposed AD by January 10, 2007.

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 Wagner, Aerospace Engineer, Airframe and Propulsion Branch, ANE-172, FAA, New York Aircraft Certification Office, 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 “FAA-2006-26558; Directorate Identifier 2006-NM-206-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 any of our dockets, 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

Transport Canada Civil Aviation (TCCA), which is the airworthiness authority for Canada, notified us that an unsafe condition may exist on certain Bombardier Model DHC-8-102, -103, and -106 airplanes, and Model DHC-8-200 and DHC-8-300 series airplanes. TCCA advises that a Model DHC-8 airplane encountered an uncommanded propeller feathering during climb, which resulted in an emergency landing. Investigation showed that the wing-to-fuselage aft seal assembly had chafed through the wires associated with the auto-feather control system. Chafing or grounding of the wiring against the aft seal assemblies, if not corrected, could interrupt the operation of various systems, including the propeller feather control, alternating current (AC) electrical power, and standby hydraulic power, and result in reduced controllability of the airplane.

Relevant Service Information

Bombardier has issued Service Bulletin 8-24-83, Revision A, dated August 2, 2005. The service bulletin describes procedures for inspecting for damage of the electrical cable harness assembly located at the left and right wing root to fuselage aft seal, and repair if necessary. The service bulletin also describes procedures for reworking the fuselage aft seal assembly (left and right) to create a clearance between the electrical cable assemblies and the edge of the fairing panel. The rework described in Service Bulletin 8-24-83, Revision A, contains the instructions for incorporating Bombardier Modification Summary Package 8Y122031, Revision B, dated December 2, 2004. (The technical content of Bombardier Modification Summary Package IS8Q2400005, Revision C, dated January 7, 2005, is equivalent to Modification Summary Package 8Y122031, Revision B.) The rework includes removing a rivet and installing a new rivet, installing new anchor nuts with a clamp, and winding a protective layer of “spiral wrap” around the affected electrical cable assemblies. Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition. TCCA mandated the service information and issued Canadian airworthiness directive CF-2006-15, dated June 14, 2006, to ensure the continued airworthiness of these airplanes in Canada.

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, TCCA 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.

Therefore, we are proposing this AD, which would require accomplishing the actions specified in the service information described previously.

Clarification of Inspection Terminology

Where the TCCA airworthiness directive specifies to “visually inspect” and the service bulletin specifies to “inspect” the electrical cable harness assembly, this proposed AD refers to the inspection as a general visual inspection. We have included the definition for a general visual inspection in a note in the proposed AD.

Costs of Compliance

This proposed AD would affect about 136 airplanes of U.S. registry. The proposed actions would take about 4 work hours per airplane, at an average labor rate of $80 per work hour. Required parts would cost about $75 per airplane. Based on these figures, the estimated cost of the proposed AD for U.S. operators is $53,720, or $395 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 adding the following new airworthiness directive (AD):

Bombardier, Inc. (Formerly de Havilland, Inc.): Docket No. FAA-2006-26558; Directorate Identifier 2006-NM-206-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by January 10, 2007.

Affected ADs

(b) None.

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 003 through 606, inclusive.

Unsafe Condition

(d) This AD results from a report that an airplane encountered an uncommanded propeller feathering during climb, which resulted in an emergency landing. We are issuing this AD to prevent chafing or grounding of the wiring against the aft seal assemblies, which, if not corrected, could interrupt the operation of various systems, including the propeller feather control, alternating current (AC) electrical power, and standby hydraulic power, and result in reduced controllability of the airplane.

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.

Inspection and Rework

(f) Within 6,000 flight hours after the effective date of this AD, do the actions in paragraphs (f)(1) and (f)(2) of this AD. Do all actions in accordance with Bombardier Service Bulletin 8-24-83, Revision A, dated August 2, 2005. The actions in paragraph (f)(1) of this AD must be done before the rework in paragraph (f)(2) of this AD.

Note 1:

Bombardier Service Bulletin 8-24-83, Revision A, contains the instructions for incorporating Bombardier Modification Summary Package 8Y122031, Revision B, dated December 2, 2004. (The technical content of Bombardier Modification Summary Package IS8Q2400005, Revision C, dated January 7, 2004, is equivalent to Bombardier Modification Summary Package 8Y122031, Revision B.)

(1) Do a general visual inspection for damage of the electrical cable harness assembly located on the left and right wing root-to-fuselage aft seal. If any damage is found, repair the damage before further flight.

(2) Rework the fuselage aft seal assembly (left and right) to create a clearance between the electrical cable assemblies and the edge of the fairing panel.

Note 2:

For the purposes of this AD, a general visual inspection is: “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 ensure visual access to all 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.”

Actions Accomplished in Accordance With Previous Revision of Service Bulletin

(g) Actions done before the effective date of this AD in accordance with Bombardier Service Bulletin 8-24-83, dated December 23, 2004, are acceptable for compliance with the corresponding requirements in paragraph (f) of this AD.

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-2006-15, dated June 14, 2006, also addresses the subject of this AD.

Issued in Renton, Washington, on December 1, 2006.

Kevin M. Mullin,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.