Comments Invited
This AD is a final rule that involves requirements affecting flight safety, and we did not provide you with notice and an opportunity to provide your comments prior to it becoming effective. However, we invite you to participate in this rulemaking by submitting written comments, data, or views. We also invite comments relating to the economic, environmental, energy, or federalism impacts that resulted from adopting this AD. The most helpful comments reference a specific portion of the AD, explain the reason for any recommended change, and include supporting data. To ensure the docket does not contain duplicate comments, commenters should send only one copy of written comments, or if comments are filed electronically, commenters should submit them only one time. We will file
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in the docket all comments that we receive, as well as a report summarizing each substantive public contact with FAA personnel concerningthis rulemaking during the comment period. We will consider all the comments we receive and may conduct additional rulemaking based on those comments.
Discussion
On September 29, 2011, we issued AD 2011-21-13 (76 FR 68299, November 4, 2011), for all ECD model MBB-BK 117 C-2 helicopters. Our AD 2011-21-13 was based on European Aviation Safety Agency (EASA) Emergency AD No. 2010-0268-E, dated December 21, 2010 (EAD 2010-0268- E), requiring the introduction of additional RFM procedures to monitor the electrical power display generator amperes (GEN AMPS) on the Vehicle and Engine Multifunction Display (VEMD) during switching of the generator. EASA advised that some ECD MBB-BK117 C-2 helicopters detected an excessive current flow when one generator was deactivated. This situation, if not detected and corrected, could lead to failure of the generator, likely resulting in loss of electrical power and inducing loss of systems that are necessary for safe flight. To address this unsafe condition, AD 2011-21-13 requires revising the ``Emergency and Malfunction Procedures'' and the ``Performance Data'' sections of the RFM by inserting three temporary pages from ECD Alert Service Bulletin (ASB) No. ASB MBB BK117 C-2-24A-008, dated December 20, 2010 (MBB BK117 C-2-24A-008). Those pages require operators to insert pages into the RFM, which provide that pilots visually monitor the power display GEN AMPS on the VEMD for too high of a current when a generator is shut down, such as during the ENGINE POWER CHECK. These revised RFM provisions provide for switching off the two main electrical buses on the overhead panel to prevent the operating generator from being damaged when the other generator is shut down. We issued AD 2011-21-13 to prevent failure of a generator, which could result in loss of electrical power, loss of systems necessary for flight safety, and subsequent loss of control of the helicopter.
Actions Since Existing AD Was Issued
Before we issued AD2011-21-13 (76 FR 68299, November 4, 2011), EASA, which is the Technical Agent for the Member States of the European Union, issued EASA AD No. 2011-0162, dated August 30, 2011 (AD 2011-0162). In AD 2011-0162, EASA states that ECD has developed a modification to prevent the possibility of too high current flow when a generator is deactivated, and updated the RFM procedures accordingly. This EASA AD requires the RFM changes introduced by EAD 2010-0268-E to be removed. The EASA AD also requires modification of the Generator Relay left-hand and right-hand After Junction Boxes by removing diodes, CR10007 and CR10008, respectively, on ECD MBB-BK117 C-2 helicopters, serial numbers 9004 through 9500. Through this AD action, the FAA is requiring this same modification to the After Junction Boxes in helicopters registered in the United States and removal of the same pages from the RFM that were introduced by AD 2011-21-13.
FAA's Determination
These helicopters have been approved by the aviation authority of the Federal Republic of Germany (FRG) and are approved for operation in the United States. Pursuant to our bilateral agreement with the FRG, EASA, their technical representative, has notified us of the unsafe condition described in the EASA AD. We are issuing this AD because we evaluated all information provided by EASA and determined the unsafe condition is likely to exist or develop on other helicopters of the same type design.
Related Service Information
We reviewed ECD ASB MBB BK117 C-2-24A-008, Revision 1, dated August 29, 2011. The ASB describes procedures for removing two diodes on the generator relays in the After Junction Boxes. EASA classified this ASB as mandatory and issued AD 2011-0162 to ensure the continued airworthiness of these helicopters.
AD Requirements
This AD requires, within 30 days, removing temporary pages from the RFM that were inserted for AD 2011-21-13. This AD also requires modifying Generator Relay left-hand and right-hand After Junction Boxes by removing diodes, CR10007 and CR10008.
Differences Between This AD and the EASA AD
The EASA AD requires compliance by September 6, 2011; the FAA requires compliance within 30 days from the effective date of the AD.
Costs of Compliance
We estimate that this AD affects 232 helicopters of U.S. Registry. We estimate that operators may incur the following costs in order to comply with this AD. Removing the diodes from the after junction boxes will require 2 work hours at an average labor cost of $85 per hour and incorporating the changes into the RFM will require .5 work hour for a total cost per operator of $213 and a cost to the entire U.S. fleet of $49,416.
FAA's Justification and Determination of the Effective Date
Providing an opportunity for public comments prior to adopting these AD requirements would delay implementing the safety actions needed to correct this known unsafe condition. Therefore, we find that the risk to the flying public justifies waiving notice and comment prior to the adoption of this rule because the required corrective actions must be accomplished within 30 days.
Since an unsafe condition exists that requires the immediate adoption of this AD, we determined that notice and opportunity for public comment before issuing this AD are impracticable and contrary to the public interest and that good cause exists for making this amendment effective in less than 30 days.
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, I certify that this AD:
1. Is not a ``significant regulatory action'' under Executive Order 12866;
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2. Is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979);
3. Will not affectintrastate aviation in Alaska to the extent that it justifies making a regulatory distinction; 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.
We prepared an economic evaluation of the estimated costs to comply with this AD and placed it in the AD docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.