AD 2018-02-16

We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc., Model DHC-8-400 series airplanes. This AD was prompted by reports that operation of fuselage doors was interrupted due to corrosion in certain door roller bearings. This AD requires a one-time detailed inspection of the bearings for corrosion, and replacement if necessary. We are issuing this AD to address the unsafe condition on these products.

Final rule.

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

0 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]

0 2. The FAA amends Sec. 39.13 by adding the following new airworthiness directive (AD):

2018-02-16 Bombardier, Inc.: Amendment 39-19169; Docket No. FAA- 2017-0621; Product Identifier 2017-NM-049-AD.

(a) Effective Date

This AD is effective March 5, 2018.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Bombardier, Inc., Model DHC-8-400, -401, and -402 airplanes, certificated in any category, serial numbers 4001 and 4003 through 4488 inclusive, except those incorporating Bombardier ModSum IS4Q5200050.

(d) Subject

Air Transport Association (ATA) of America Code 52, Doors.

(e) ReasonThis AD was prompted by reports of interrupted operation of translating fuselage doors caused by corrosion in the door lift and latch shaft roller bearings. We are issuing this AD to detect and correct bearing corrosion and prevent door operation interruptions that could inhibit safe evacuation of the airplane in an emergency.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Inspection and Replacement of Bearings

Within 6,000 flight hours or 36 months after the effective date of this AD, whichever occurs earlier, do a detailed visual inspection of all translating fuselage door lift and latch shaft roller bearings for signs of corrosion, damaged seals, and loss of lubricant; replace any corroded bearings; and apply corrosion- inhibiting compound (CIC); in accordance with paragraph 3.B., ``Procedure,'' of the Accomplishment Instructions of Bombardier Service Bulletin 84-52-88, dated April 14, 2016.

(h) Creditfor Previous Actions

This paragraph provides credit for actions required by paragraph (g) of this AD, if those actions were performed before the effective date of this AD using Bombardier Service Bulletin 84-52-85, dated September 23, 2015; or Bombardier Service Bulletin 84-52-85, Revision A, dated January 22, 2016.

(i) Other FAA AD Provisions

The following provisions also apply to this AD:
(1) Alternative Methods of Compliance (AMOCs): The Manager, New York ACO Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the certification office, send it to ATTN: Program Manager, Continuing Operational Safety, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7300; fax 516-794-5531. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.
(2) Contacting the Manufacturer: For any requirement in this AD to obtain corrective actions from a manufacturer, the action must be accomplished using a method approved by the Manager, New York ACO Branch, FAA; or Transport Canada Civil Aviation (TCCA); or Bombardier, Inc.'s TCCA Design Approval Organization (DAO). If approved by the DAO, the approval must include the DAO-authorized signature.

(j) Related Information

(1) Refer to Mandatory Continuing Airworthiness Information (MCAI) Canadian Airworthiness Directive CF-2016-18, dated June 6, 2016, for related information. This MCAI may be found in the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017-0621.
(2) For more information about this AD, contact Aziz Ahmed, Aerospace Engineer, Airframe and Mechanical Systems Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7329; fax 516-794-5531.
(3) Service information identified in this AD that is not incorporated by reference is available at the addresses specified in paragraphs (k)(3) and (k)(4) of this AD.

(k) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference (IBR) of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) You must use this service information as applicable to do the actions required by this AD, unless this AD specifies otherwise.
(i) Bombardier Service Bulletin 84-52-88, dated April 14, 2016.
(ii) Reserved.
(3) For service information identified in this AD, contact Bombardier, Inc., Q-Series Technical Help Desk, 123 Garratt Boulevard, Toronto, Ontario M3K 1Y5, Canada; telephone 416-375-4000;fax 416-375-4539; email thd.qseries@aero.bombardier.com; internet http://www.bombardier.com.
(4) You may view this service information at the FAA, Transport Standards Branch, 1601 Lind Avenue SW, Renton, WA. For information on the availability of this material at the FAA, call 425-227-1221.
(5) You may view this service information that is incorporated by reference 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.

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to certain Bombardier, Inc., Model DHC-8-400 series airplanes. The NPRM published in the Federal Register on June 21, 2017 (82 FR 28269) (``the NPRM''). The NPRM was prompted by reports that operation of fuselage doors was interrupted due to corrosion in certain door roller bearings. The NPRM proposed to require a one-time detailed inspection of the bearings for corrosion, and replacement if necessary. We are issuing this AD to detect and correct bearing corrosion and prevent door operation interruptions that could inhibit safe evacuation of the airplane in an emergency.
Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued Canadian Airworthiness Directive CF- 2016-18, dated June 6, 2016 (referred to after this as the Mandatory Continuing Airworthiness Information, or ``the MCAI''), to correct an unsafe condition for certain Bombardier, Inc., Model DHC-8-400 series airplanes. The MCAI states:

A number of translating fuselage door operation interruptions has been reported. In one case, the Aft Service door could not be opened. It was found that the door lift latch bearings had corroded, which prevented the door from opening.

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The translating doors are classified as emergency exits. The inability to open an emergency exit could inhibit evacuation in the event of an emergency. This [Canadian] AD is issued to mandate a one-time inspection of the translating door bearings to check for corrosion, replace bearings if required, and apply Corrosion Inhibiting Compound (CIC).

You may examine the MCAI in the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017- 0621.

Comments

We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the NPRM and the FAA's response to each comment. The Air Line Pilots Association, International (ALPA) supported the NPRM.

Request To Remove Certain Service Information Procedures

Horizon Air requested that we change the language in paragraph (g) of the proposed AD to exclude the ``Job Set-Up'' and ``Close Out'' sections of the Accomplishment Instructions, because accomplishing those sections does not correct the unsafe condition, and requiring them restricts an operator's ability to perform other maintenance in conjunction with the requirements of the AD. Horizon Air requested that the final rule mandate only paragraph 3.B., ``Procedure,'' of the Accomplishment Instructions of Bombardier Service Bulletin 84-52-88, dated April 14, 2016.
We agree with the commenter's request to exclude the ``Job Set-up'' and ``Close Out'' sections of the Accomplishment Instructions of Bombardier Service Bulletin 84-52-88, dated April 14, 2016, because they are not required toaddress the unsafe condition identified in this AD. We have revised paragraph (g) of this AD to require only accomplishment of paragraph 3.B., ``Procedure,'' of the Accomplishment Instructions of Bombardier Service Bulletin 84-52-88, dated April 14, 2016.

Conclusion

We reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this AD with the change described previously and minor editorial changes. We have determined that these minor changes:
Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and
Do not add any additional burden upon the public than was already proposed in the NPRM.
We also determined that these changes will not increase the economic burden on any operator or increase the scope of this AD.

Related Service Information Under 1 CFR part 51

Bombardier has issued Service Bulletin 84-52-88, dated April 14, 2016. This service information describes procedures for identification of corrosion in fuselage door bearings, replacement if necessary, and CIC application. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

Costs of Compliance

We estimate that this AD affects 143 airplanes of U.S. registry.
We estimate the following costs to comply with this AD:

Estimated Costs ----------------------------------------------------------------------------------------------------------------
Cost per Cost on U.S.
Action Labor cost Parts cost product operators ---------------------------------------------------------------------------------------------------------------- Inspection and CIC application..... 8 work-hours x $85 per hour $0 $680 $97,240
= $680 for 3 doors. ----------------------------------------------------------------------------------------------------------------

We estimate the following costs to do any necessary replacements that would be required based on the results of the inspection. We have no way of determining the number of aircraft that might need this replacement:

On-condition CostsEstimated Costs ----------------------------------------------------------------------------------------------------------------
Action Labor cost Parts cost Cost per product ---------------------------------------------------------------------------------------------------------------- Replacement........................... 4 work-hours x $85 per hour = $432 $772 per door.
$340 per door. ----------------------------------------------------------------------------------------------------------------

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.
This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to transport category airplanes to the Director of the System Oversight Division.

Regulatory Findings

We 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:

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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);
3. Will not affect intrastate aviation in Alaska; and
4. Will not have a significant economicimpact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.