01-7705. Airworthiness Directives; Bombardier Model DHC-8-200 and -300 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Bombardier Model DHC-8-200 and -300 series airplanes, that currently requires repetitive inspections to detect chafing or arcing damage to the cable/wire and fuel tube assemblies on the right-hand side of each engine, and replacement with new components, if necessary. That AD also provides for an optional terminating action for the repetitive inspections required by that AD. This proposal would require accomplishment of the previously optional terminating action. This action is necessary to prevent chafing of the cable/wire bundles against the fuel line, which could result in arcing and a consequent fire or explosion. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by April 30, 2001.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-25-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2001-NM-25-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 for Windows or ASCII text.

The service information referenced in the proposed rule may be obtained from Bombardier, Inc., Bombardier Regional Aircraft Division, 123 Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, New York Aircraft Certificaiton Office, 10 Fifth Street, Third Floor, Valley Stream, New York.

FOR FURTHER INFORMATION CONTACT:

James Delisio, Aerospace Engineer, Airframe and Propulsion Branch, ANE-171, FAA, New York Aircraft Certification Office, 10 Fifth Street, Third Floor, Valley Stream, New York 11581; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed 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 above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this action may be changed in light of the comments received.

Submit comments using the following format:

• Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
• For each issue, state what specific change to the proposed AD is being requested.
• Include justification (e.g., reasons or data) for each request.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2001-NM-25-AD.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-25-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

On January 12, 2001, the FAA issued AD 2001-02-02, amendment 39-12086 (66 FR 6454, January 22, 2001), applicable to certain Bombardier Model DHC-8-200 and -300 series airplanes, to require repetitive inspections to detect chafing or arcing damage to the cable/wire and fuel tube assemblies on the right-hand side of each engine, and replacement with new components, if necessary. That AD also provides for an optional terminating action for the repetitive inspections required by that AD. That action is necessary to prevent chafing of the cable/wire bundles against the fuel line, which could result in arcing and a consequent fire or explosion.

Actions Since Issuance of Previous Rule

In the preamble to AD 2001-02-02, the FAA indicated that certain actions required by that AD were considered “interim action” and that further rulemaking action was being considered to require modification of the cable assembly, which would constitute terminating action for the repetitive inspections required by that AD. However, the planned compliance time for the installation of the modification was sufficiently long so that notice and opportunity for prior public comment was practicable. The FAA now has determined that further rulemaking action is indeed necessary, this proposed AD follows from that determination.

Explanation of Relevant Service Information

Bombardier has issued Revision A, dated December 12, 2000, and Revision B, dated January 30, 2001, of Alert Service Bulletin A8-73-23. These revisions describe procedures for repetitive general visual inspections to detect chafing or arcing damage to the cable and the fuel tube assemblies on the right hand side of each engine, and replacement with new components, if necessary. These revisions also describe procedures for an optional modification that entails, among other things, rerouting the existing wire harness to the opposite side of the oil cooler, and shortening and securing the wire harness, if necessary. That modification eliminates the need for the repetitive inspections. Revisions A and B of the alert service bulletin (ASB) specify certain corrections to the original ASB regarding part numbers and certain other accomplishment instructions. (The original version of ASB A8-73-23, dated November 3, 2000, was previously specified as the appropriate service information in AD 2001-02-02.) Accomplishment of the actions specified in either Revision A or Revision B of the ASB is intended to adequately address the identified unsafe condition. Transport Canada Civil Aviation (TCCA), which is the airworthiness authority of Canada, has classified Revisions A and B of ASB A8-73-23 as mandatory and issued Canadian airworthiness directive CF-2000-33, dated November 14, 2000, in order to assure the continued airworthiness of these airplanes in Canada.

FAA's Conclusions

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. The FAA has examined the findings of the TCCA, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design registered in the United States, the proposed AD would supersede AD 2001-02-02 to continue to require repetitive inspections to detect chafing or arcing damage to the cable/wire and fuel tube assemblies on the right-hand side of each engine, and replacement with new components, if necessary. The proposed AD also would require certain modification procedures that specify, among other actions, rerouting the existing wire harness to the opposite side of the oil cooler. Accomplishment of the modification would constitute terminating action for the repetitive inspections. The actions would be required to be accomplished in accordance with the ASB's described above.

Cost Impact

There are approximately 150 airplanes of U.S. registry that would be affected by this proposed AD.

The repetitive inspections that are currently required by AD 2001-02-02, and retained in this proposed AD, take approximately 2 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the currently required actions on U.S. operators is estimated to be $18,000, or $120 per airplane, per inspection cycle.

The new action, incorporation of the modification, that is proposed in this AD action, would take approximately 4 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts would cost approximately $350 per airplane. Based on these figures, the cost impact of the proposed requirements of this AD on U.S. operators is estimated to be $88,500, or $590 per airplane.

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the current or proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact

The regulations proposed herein 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. Therefore, it is determined that this proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this 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) if promulgated, 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. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting 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

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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.

§ 39.13

[Amended]

2. Section 39.13 is amended by removing amendment 39-12086 (66 FR 6454, January 22, 2001), and by adding a new airworthiness directive (AD), to read as follows:

Bombardier, Inc. (Formerly de Havilland, Inc.): Docket 2001-NM-25-AD. Supersedes AD 2001-02-02, Amendment 39-12086.

Applicability: Model DHC-8-201, -202, -301, -311, and -315 series airplanes, having serial numbers 100 through 552 inclusive, certificated in any category.

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 (d) 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 possible arcing between the electrical wiring and the fuel tube, which could result in a fire or explosion, accomplish the following:

Inspection Requirements of AD 2000-02-02

(a) Within 50 flight hours or 10 days after February 6, 2001 (the effective date of AD 2001-02-02), whichever occurs first: Do a general visual inspection to detect chafing or arcing damage to the cable and the fuel tube assemblies on the right hand side of each engine, per Bombardier Alert Service Bulletin A8-73-23, Revision A, dated December 12, 2000, or Revision B, dated January 30, 2001. Repeat the inspection every 500 flight hours or 3 months, whichever occurs first.

Note 2:

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 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.”

Repair

(b) If any damage to the fuel tube or cable assembly is detected, before further flight, replace the damaged component per Bombardier Alert Service Bulletin A8-73-23, Revision A, dated December 12, 2000, or Revision B, dated January 30, 2001. Thereafter, repeat the inspection required by paragraph (a) of this AD every 500 flight hours or 3 months, whichever occurs first.

Note 3:

Accomplishment of the replacement actions specified in paragraph (b) of this AD or terminating action required by paragraph (c) of this AD, per Bombardier Alert Service Bulletin A8-73-23 (original version), dated November 30, 2000, before the effective date of this AD, is acceptable for compliance with paragraphs (b) or (c) of this AD, as applicable.

Terminating Action

(c) Within 1,000 flight hours or 6 months after the effective date of this AD, whichever occurs first: Accomplish the modification instructions described in Bombardier Alert Service Bulletin A8-73-23, Revision A, dated December 12, 2000, or Revision B, dated January 30, 2001, that specify, among other actions, rerouting the existing wire harness to the opposite side of the oil cooler. Accomplishment of the modification constitutes terminating action for the repetitive inspection requirements of this AD.

Alternative Methods of Compliance

(d) 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, New York Aircraft Certification Office (ACO), FAA. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, New York ACO.

Note 4:

Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the New York ACO.

Special Flight Permits

(e) Special flight permits may be issued in accordance with §§ 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.

Note 5:

The subject of this AD is addressed in Canadian airworthiness directive CF-2000-33, dated November 14, 2000.

Issued in Renton, Washington, on March 22, 2001.

Donald L. Riggin,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.