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 BD-700-1A10 and BD-700-1A11 airplanes. The NPRM published in the Federal Register on March 4, 2016 (81 FR 11471) (``the NPRM'').
Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued Canadian Airworthiness Directive CF- 2014-39, dated November 4, 2014 (referred to after this as the Mandatory Continuing Airworthiness Information, or ``the MCAI''), to correct an unsafe condition for certain Bombardier, Inc. Model BD-700- 1A10 and BD-700-1A11 airplanes. The MCAI states:
Following the issuance of [Canadian] AD CF-2010-14, additional qualification testing of the passenger door tensator spring, Part Number (P/N) GS321-0580-1, determined that the tensator springs could be susceptible to failure prior to reaching the life limit mandated by [Canadian] AD CF-2010-14.
In addition, there have been in-service reports of passenger door tensator spring failures. Investigation determined that the material used to manufacture the tensator springs [was] improperly heat treated.
The passenger door assembly is installed with four tensator springs that assist the door actuator in opening and closing the door. In-service experience has shown that a failed tensator spring could uncoil and foul up the rotating tensator spools, resulting in the inability to open the main passenger door. The inability to open the main passenger door could impede evacuation in the event of an emergency.
This [Canadian] AD mandates the revision to the approved maintenance schedule to reduce the repetitive discard task interval and mandates the replacement of non-conforming tensator springs.
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-2016- 3989.
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.
Request To Include Service Information
Bombardier, Inc. requested that we revise the Related Service Information under 1 CFR part 51 section and paragraph (g) of the proposed AD to include Temporary Revision (TR) 5-2-10, dated September 9, 2014, to Part 2, Section 5-10-11, of Bombardier Global 5000 GL 5000 Featuring Global Vision Flight Deck--Time Limits/Maintenance Checks.
We agree to include TR 5-2-10, dated June 4, 2014, to Part 2, Section 5-10-11, of Bombardier Global 5000 GL 5000 Featuring Global Vision Flight Deck--Time Limits/Maintenance Checks, as requested by the commenter. Our intent is to correspond with TCCA Canadian AD CF-2014- 39, dated November 4, 2014, which includes TR 5-2-9, dated September 9, 2014, to Part 2, Section 5-10-11, of Bombardier Global 5000 GL 5000 Featuring Global Vision Flight
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Deck--Time Limits/Maintenance Checks. TR 5-2-10, dated June 4, 2014, supersedes TR 5-2-9, dated September 9, 2014. We have included TR 5-2- 10, dated June 4, 2014, in paragraph (g)(2) of this AD and redesignated subsequent paragraph identifiers accordingly. We have also included that same TR in the Related Service Information under 1 CFR part 51 section of this final rule. Since the NPRM inadvertently did not include a TR to Part 2, Section 5-10-11, of Bombardier Global 5000 GL 5000 Featuring Global Vision Flight Deck--Time Limits/Maintenance Checks, we must make this change to avoid operators needing to ask for approval of an alternative method of compliance (AMOC) to use a TR in order to comply with the revision required by paragraph (g) of this AD.
In addition, we have revised paragraph (g) of this AD to refer to Task Number 52-11-41-101 because some TRs include multiple tasks. This AD specifically addresses the passenger door tensator spring, part number GS321-0580-1, and the task number in the TRs for that component is 52-11-41-101.
Request To Correct Typographical Error
Bombardier, Inc. requested that we revise paragraph (g)(2) of the proposed AD to read ``Model BD-700-1A10 airplanes,'' instead of ``Model BD-700-1A11 airplanes.''
We agree. This was a typographical error, and has been corrected in paragraph (g)(3) of this AD (paragraph (g)(2) of the proposed AD).
Request To Revise Compliance Time
NetJets requested that we revise the proposed AD so that the threshold for the initial spring replacement is based on the AD effective date, and not the TR revision date. NetJets explained that paragraph (g) of the proposed AD specifies that the compliance time for the initial replacement is per the TRs listed in paragraphs (g)(1) through (g)(4) of the proposed AD, or within 30 days after the AD effective date, whichever occurs later. NetJets explained further that the TRs base the threshold from the TR revision date of ``Jun 04/ 2014,'' and that by the time the final rule is released, the threshold in the TR will have been exceeded by approximately 2 years. NetJets argued that, therefore, the final rule will effectively mandate a 30- day threshold, which is an undue burden without technical justification.
We do not agree with the request to revise the compliance time in this AD. The compliance time in this AD corresponds with the compliance time in Canadian AD CF-2014-39, dated November 4, 2014. In addition, the commenter did not provide any data to substantiate that extending the compliance time would provide an acceptable level of safety. After considering all the available information, we have determined that the compliance time, as proposed, represents an appropriate interval of time in which the required actions can be performed in a timely manner within the affected fleet, while still maintaining an adequate level of safety. Under the provisions of paragraph (k)(1) of this AD, however, we may consider requests for adjustments to the compliance time if data are submitted to substantiate that such an adjustment would provide an acceptable level of safety. We have made no changes to this AD in this regard.
Request To Allow for Later-Approved Revisions of Service Information
NetJets requested that we revise the NPRM to add provisions to allow later FAA-approved revisions to the time limits/maintenance checks manuals (TLMCM), so that an approval of an AMOC will not be required to incorporate the currently published TLMCM revision and future revisions. NetJets explained that the TRs specified in paragraphs (g)(1) through (g)(4) of the proposed AD have been incorporated in revisions to the listed TLMCMs.
We find that clarification is necessary. Once operators have incorporated the task in the TR into their maintenance or inspection program, the task cannot be changed without approval of an AMOC. However, once the task in the TR is incorporated into the TLMCM, operators that use the TLMCM are still in compliance because the task has not changed. If a future revision of the TLMCM changes the task, then an AMOC would be needed to use the revised task.
We have revised paragraph (g) of this AD to clarify that the revision may be done by inserting copies of the TRs identified in paragraphs (g)(1) through (g)(5) of this AD into the applicable TLMCM. When the information in a TR has been included in general revisions of the applicable TLMCM, the general revisions may be inserted in the TLMCM, and the TR may be removed.
Request for Clarification of the Necessity for a Life Limit Requirement
NetJets requested that we clarify the necessity for the life limit requirement in paragraph (i) of the proposed AD. NetJets stated that paragraph (i) of the proposed AD requires a threshold of ``. . . but not exceeding the applicable life limit of the passenger tensator spring . . .'' without identifying the referenced life limit, and noted that the listedservice information does not include a life limit requirement.
We agree to clarify the requirement specified in paragraph (i) of this AD and the necessity for that requirement. The passenger door assembly is installed with four tensator springs that assist the door actuator in opening and closing the door. In-service experience has shown that a failed tensator spring could uncoil and foul up the rotating tensator spools, resulting in the inability to open the main passenger door. The inability to open the main passenger door could impede evacuation in the event of an emergency. The actions required by this AD are necessary to address the identified unsafe condition.
Paragraph (g) of this AD mandates the revision to the approved maintenance schedule by incorporating TRs to reduce the repetitive discard task interval. Paragraph (i) of this AD mandates, for certain airplanes, the replacement of non-conforming tensator springs within 15 months after the effective date of this AD, butnot exceeding the applicable life limit of 1,500 landings for the component as listed in the applicable TRs identified in paragraph (g) of this AD. The replacement is necessary to ensure the airplanes identified in section 1.A., ``Effectivity,'' of Bombardier Global 5000 Service Bulletin 700- 1A11-52-023, dated October 4, 2013; or Bombardier Global Express/Global Express XRS Service Bulletin 700-52-046, dated October 4, 2013, replace the tensator springs within 15 months, as specified in that service information, but not later than the new life limit. We have revised paragraph (i) of this AD to refer to the TRs in paragraph (g) of this AD for the life limit.
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 changes 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.
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Related Service Information Under 1 CFR Part 51
We reviewed the following Bombardier, Inc. service information:
Bombardier Global 5000 Service Bulletin 700-1A11-52-023, dated October 4, 2013.
Bombardier Global Express/Global Express XRS Service Bulletin 700-52-046, dated October 4, 2013.
TR 5-2-7, dated June 4, 2014, to Part 2, Section 5-10-11, of Bombardier Global Express XRS BD-700 Time Limits/Maintenance Checks (for Model BD-700-1A10 airplanes).
TR 5-2-10, dated September 9, 2014, to Part 2, Section 5- 10-11, of Bombardier Global 5000 GL 5000 Featuring Global Vision Flight Deck--Time Limits/Maintenance Checks (for Model BD-700-1A11 airplanes).
TR 5-2-10, dated September 9, 2014, to Part 2, Section 5- 10-11, of Bombardier Global 6000 GL 6000 Time Limits/Maintenance Checks (for Model BD-700-1A10 airplanes).
TR 5-2-13, dated June 4, 2014, to Part 2, Section 5-10-11, of Bombardier Global 5000 BD-700 Time Limits/Maintenance Checks (for Model BD-700-1A11 airplanes).
TR 5-2-44, dated June 4, 2014, to Part 2, Section 5-10-11, of Bombardier Global Express BD-700 Time Limits/Maintenance Checks (for Model BD-700-1A10 airplanes).
The service information describes procedures for replacing passenger door tensator springs with new springs. 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 60 airplanes of U.S. registry.
We also estimate that it would take about 40 work-hours per product to comply with the basic requirements of this AD. The average labor rate is $85 per work-hour. Based on these figures, we estimate the cost of this AD on U.S. operators to be $204,000, or $3,400 per product.
According to the manufacturer, some of the costs of this AD may be covered under warranty, thereby reducing the cost impact on affected individuals. We do not control warranty coverage for affected individuals. As a result, we have included all costs in our cost estimate.
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 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 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 economic impact, 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.