E7-10670. Airworthiness Directives; Bombardier Model DHC-8-100, DHC-8-200, and DHC-8-300 Series Airplanes

AGENCY:

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

ACTION:

Final rule.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for certain Bombardier Model DHC-8-100, DHC-8-200, and DHC-8-300 series airplanes. This AD requires, for certain airplanes, modification of the upper bearing of the main landing gear (MLG) shock strut. This AD also requires, for certain airplanes, revising the de Havilland DHC-8 Maintenance Program Manual to include the MLG shock strut servicing task. This AD results from reports of over-extension of the MLG shock strut piston, which allows the torque links to go over-center and rest on the piston. We are issuing this AD to prevent loss in shock absorption during touchdown and failure of the shock strut housing, which could result in a subsequent loss of directional control.

DATES:

This AD becomes effective July 10, 2007.

The Director of the Federal Register approved the incorporation by reference of certain publications listed in the AD as of July 10, 2007.

ADDRESSES:

You may examine the AD docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC.

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

FOR FURTHER INFORMATION CONTACT:

Mazdak Hobbi, Aerospace Engineer, Airframe and Propulsion Branch, ANE-171, FAA, New York Aircraft Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, New York 11590; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Examining the Docket

You may examine the airworthiness directive (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 street address stated in the ADDRESSES section.

Discussion

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to certain Bombardier Model DHC-8-100, DHC-8-200, and DHC-8-300 series airplanes. That NPRM was published in the Federal Register on March 29, 2007 (72 FR 14721). That NPRM proposed to require, for certain airplanes, modification of the upper bearing of the main landing gear (MLG) shock strut. That NPRM proposed to also require, for certain airplanes, revising the de Havilland DHC-8 Maintenance Program Manual to include the MLG shock strut servicing task.

Comments

We provided the public the opportunity to participate in the development of this AD. We received no comments on the NPRM or on the determination of the cost to the public.

Clarification of Part Number

We have revised paragraph (i)(2) of this final rule to correct a typographical error, which resulted in an incorrect part number. Paragraph (i)(2) should have read “* * * 10129-5 or 10129-553.”

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.

Conclusion

We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

The following table provides the estimated costs for U.S. operators to comply with this AD.

Estimated Costs

Action	Work hours	Average labor rate per hour	Parts	Cost per airplane	Number of U.S.-registered airplanes	Fleet cost
Modification	4	$80	$274	$594	Up to 135	Up to $80,190.
Manual Revision	1	80	0	80	135	$10,800.

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 AD will not have federalism implications under Executive Order 13132. This AD will 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 this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866;

(2) Is not a “significant rule” under 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 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
• Incorporation by reference
• Safety

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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):

2007-12-01 Bombardier, Inc. (Formerly de Havilland, Inc.): Amendment 39-15079. Docket No. FAA-2007-27713; Directorate Identifier 2006-NM-240-AD.

Effective Date

(a) This AD becomes effective July 10, 2007.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Bombardier Model DHC-8-101, -102, -103, -106, -201, -202, -301, -311, -314, and -315 airplanes, certificated in any category; serial numbers 003 through 618 inclusive.

Unsafe Condition

(d) This AD results from reports of over-extension of the main landing gear (MLG) shock strut piston, which allows the torque links to go over-center and rest on the piston. We are issuing this AD to prevent loss in shock absorption during touchdown and failure of the shock strut housing, which could result in a subsequent loss of directional control.

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.

Modification of the Upper Bearing

(f) For Model DHC-8-311, -314, and -315 airplanes, serial numbers 202 through 516 inclusive, with MLG shock struts having any serial number DCL3501/90 through DCL3768/97 inclusive installed: Within 3,000 flight hours after the effective date of this AD, modify the upper bearing in each MLG (including doing inspections of the upper bearing and cylinder bore for wear and damage, and doing all applicable corrective actions) in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 8-32-144, Revision ‘A,' dated April 29, 2002, which includes Messier-Dowty Service Bulletin M-DT SBDHC8-32-82, Revision 1, dated July 5, 2001, except if wear exceeds the maximum diameter specified in the service bulletin for the cylinder bore or if damage is found on the cylinder bore, before further flight, repair using a method approved by either the Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA; or Transport Canada Civil Aviation (TCCA) (or its delegated agent). Do all applicable corrective actions before further flight.

Revision of the Maintenance Program Manual

(g) For Model DHC-8-101, -102, -103, -106, -201, -202, -301, -311, -314, and -315 airplanes, serial numbers 003 through 614 inclusive: Within 30 days after the effective date of this AD, revise Part 1 of the applicable de Havilland DHC-8 Maintenance Program Manual by incorporating the applicable MLG shock strut servicing Task 3210/15 specified in Table 1 of this AD.

Note 1:

This may be done by inserting copies of the applicable task into the applicable maintenance program manual. When these tasks have been included in the general revisions of the applicable maintenance program manual, the general revisions may be inserted in the applicable maintenance program manual and the copy of the task may be removed from the maintenance program manual.

Table 1.—Tasks

Task—	Dated—	To the de Havilland Program Support Manual (PSM)—	For model—
de Havilland Dash 8 Series 100 Maintenance Task Card 3210/15	June 22, 2005	1-8-7	DHC-8-100 series airplanes.
de Havilland Dash 8 Series 200 Maintenance Task Card 3210/15	June 22, 2005	1-82-7	DHC-8-200 series airplanes.
de Havilland Dash 8 Series 300 Maintenance Task Card 3210/15	November 29, 2005	1-83-7	DHC-8-300 series airplanes.

Parts Installation

(h) After the effective date of this AD, no person may install a part identified in paragraphs (h)(1) and (h)(2) of this AD, as a replacement during the repair or overhaul of any shock strut assembly, on any airplane.

(1) Upper bearing, part number 10130-3 or 10130-551.

(2) Damper ring, part number 10129-3 or 10129-551.

(i) After the effective date of this AD, only the parts identified in paragraphs (i)(1) and (i)(2) of this AD may be installed on any airplane as replacement upper bearings and damper rings during the repair or overhaul of any shock strut assembly, except as provided by paragraph (j) of this AD.

(1) Upper bearing, part number 10130-5.

(2) Damper ring, part number 10129-5 or 10129-553.

(j) After the effective date of this AD, only MLGs with a reworked, oversize cylinder bore (part number identified in the applicable component maintenance manual (CMM)) that have parts identified in paragraphs (j)(1), (j)(2), and (j)(3) of this AD used in accordance with the applicable CMM may be installed on any airplane.

(1) Upper bearing, part number CRS85-167-11.

(2) Damper ring, part number CRS85-167-31 or CRS85-167-33.

(3) Seal carrier, part number CRS85-167-21.

Credit for Actions Done Using Previous Service Information

(k) Modifications accomplished before the effective date of this AD in accordance with Bombardier Service Bulletin 8-32-144, dated August 10, 1998, which includes Messier-Dowty Service Bulletin M-DT SBDHC8-32-82, dated March 9, 1998, are considered acceptable for compliance with the corresponding actions specified in this AD.

Alternative Methods of Compliance (AMOCs)

(l)(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) 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.

Related Information

(m) Canadian airworthiness directive CF-2006-14, dated June 14, 2006, also addresses the subject of this AD.

Material Incorporated by Reference

(n) You must use Bombardier Service Bulletin 8-32-144, Revision ‘A,’ dated April 29, 2002, which includes Messier-Dowty Service Bulletin M-DT SBDHC8-32-82, Revision 1, dated July 5, 2001; and the task cards identified in Table 2 of this AD; to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference of these documents in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact Bombardier, Inc., Bombardier Regional Aircraft Division, 123 Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada, for a copy of this service information. You may review copies at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/​federal-register/​cfr/​ibr-locations.html.

Table 2.—Task Cards Incorporated by Reference

Task card—	Dated—	To the de Havilland program support manual—
de Havilland Dash 8 Series 100 Maintenance Task Card 3210/15	June 22, 2005	1-8-7.
de Havilland Dash 8 Series 200 Maintenance Task Card 3210/15	June 22, 2005	1-82-7.
de Havilland Dash 8 Series 300 Maintenance Task Card 3210/15	November 29, 2005	1-83-7.

Issued in Renton, Washington, on May 25, 2007.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.