### 54380 Federal Register / Vol. 78, No. 171 / Wednesday, September 4, 2013 / Rules and Regulations

Engineering—SEEL5, Flight Control Systems A320 Family, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France; fax +33 5 61 93 44 25. The report must include the information specified in Appendix 01 of Airbus Service Bulletin A320–27–1214.

(1) If the inspection was done on or after the effective date of this AD: Within 90 days after that inspection.

(2) If the inspection was done before the effective date of this AD: Within 90 days after the effective date of this AD.
(l) Parts Installation Limitations

As of the effective date of this AD, no person may install a THSA having P/N 47145–XXX (where XXX stands for any numerical value) on any airplane, unless that THSA meets the applicable criteria specified in paragraph (l)(1) or (l)(2) of this AD.

(1) The THSA must not have accumulated 20 years or more since the THSA’s first flight, and after installation must be inspected as required by paragraph (h) of this AD, at the later of the times specified in paragraphs (h)(1) and (h)(2) of this AD, and be inspected thereafter at intervals not to exceed 24 months as required by paragraph (h) of this AD; and any applicable actions specified in paragraph (i) of this AD must be accomplished.

(2) If the THSA has accumulated 20 years or more since the THSA’s first flight, it must have been inspected before installation as required by paragraph (h) of this AD and determined to have Type I corrosion (if the screw shaft lower splines thread condition does not meet the Type II or Type III condition), and be inspected thereafter at intervals not to exceed 24 months as required by paragraph (h) of this AD; and any applicable actions specified in paragraph (i) of this AD must be accomplished.
(m) Credit for Previous Actions

This paragraph provides credit for actions required by paragraphs (h) and (i) of this AD, if those actions were performed before the effective date of this AD using Goodrich Service Bulletin 47145–27–16, dated November 7, 2011; or Revision 1, dated August 1, 2012.
(n) Other FAA AD Provisions

The following provisions also apply to this AD:

(1) Alternative Methods of Compliance (AMOCs): The Manager, International Branch, ANM–116, Transport Airplane Directorate, 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 International Branch, send it to ATTN: Sanjay Ralhan, Aerospace Engineer, International Branch, ANM–116, Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, WA 98057–3356; telephone (425) 227–1405; fax (425) 227– 1149. Information may be emailed to: 9- ANM-116-AMOC-REQUESTS@faa.gov. 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. The AMOC approval letter must specifically reference this AD.

(2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service.

(3) Reporting Requirements: A federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to a penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a current valid OMB Control Number. The OMB Control Number for this information collection is 2120–0056. Public reporting for this collection of information is estimated to be approximately 5 minutes per response, including the time for reviewing instructions, completing, and reviewing the collection of information. All responses to this collection of information are mandatory. Comments concerning the accuracy of this burden and suggestions for reducing the burden should be directed to the FAA at: 800 Independence Ave. SW., Washington, DC 20591, Attn: Information Collection Clearance Officer, AES–200.
(o) Special Flight Permits

Special flight permits may be issued in accordance with sections 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 airplane can be modified (if the operator elects to do so), provided that, if any THSA corrosion is found during any action required by paragraph (h) of this AD, that corrosion is classified as Type I or Type II, as defined in Goodrich Service Bulletin 47145–27–16, dated November 7, 2011; Revision 1, dated August 1, 2012; or Revision 2, dated January 27, 2013. (p) Related Information

Refer to Mandatory Continuing Airworthiness Information European Aviation Safety Agency Airworthiness Directive 2012–0175, dated September 7, 2012, for related information, which can be found in the AD docket on the Internet at http://www.regulations.gov.
(q) 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 the AD specifies otherwise.

(i) Airbus Service Bulletin A320–27–1214, including Appendix 01, dated February 23,
2012.

(ii) Goodrich Service Bulletin 47145–27– 16, dated November 7, 2011. (iii) Goodrich Service Bulletin 47145–27– 16, Revision 1, dated August 1, 2012. Pages 1 through 4 of this document are identified as Revision 1, dated August 1, 2012. Pages 5 through 117 of this document are dated November 7, 2011.

(iv) Goodrich Service Bulletin 47145–27– 16, Revision 2, dated January 7, 2013. Pages 1, 2, and 4 of this document are identified as Revision 1, dated August 1, 2012. Page 3 of this document is identified as Revision 2, dated January 7, 2013. Pages 5 through 117 of this document are dated November 7,
2011.

(3) For Airbus service information identified in this AD, contact Airbus, Airworthiness Office—EIAS, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France; telephone +33 5 61 93 36 96; fax +33 5 61 93 44 51; email account.airworth-eas@ airbus.com ; Internet http://www.airbus.com

. For Goodrich service information identified in this AD, contact Goodrich Corporation, Actuation Systems, Stafford Road, Fordhouses, Wolverhampton WV10 7EH, England; telephone +44 (0) 1902 624938; fax +44 (0) 1902 788100; email techpubs.wolverhampton@goodrich.com ; Internet http://www.goodrich.com/TechPubs

.

(4) You may review copies of the service information at the FAA, Transport Airplane Directorate, 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/ibrlocations.html.

Issued in Renton, Washington, on August 23, 2013. Stephen P. Boyd, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

[FR Doc. 2013–21071 Filed 9–3–13; 8:45 am]

**BILLING CODE 4910–13–P**

**DEPARTMENT OF TRANSPORTATION**

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2013–0240; Directorate Identifier 2011–SW–060–AD; Amendment**  **39–17565; AD 2013–17–01]**

**RIN 2120–AA64**

**Airworthiness Directives; Eurocopter France Helicopters** 

**AGENCY :**  Federal Aviation Administration (FAA), DOT.

**ACTION :**  Final rule.

**SUMMARY :**  We are adopting a new airworthiness directive (AD) for certain Eurocopter France (Eurocopter) Model AS350 and AS355 helicopters. This AD


### 54381 Federal Register / Vol. 78, No. 171 / Wednesday, September 4, 2013 / Rules and Regulations

requires inspecting the tail rotor control stop screws to determine if they are correctly aligned and adjusting the screws if they are misaligned. This AD is prompted by the discovery of a loose nut on the tail rotor control stop and a misaligned tail rotor control stop screw. The actions of this AD are intended to detect a loose nut or a misaligned stop screw, which, if not corrected, could limit yaw authority, and consequently, result in a loss of helicopter control.

**DATES :**  This AD is effective October 9,
2013.

The Director of the Federal Register approved the incorporation by reference of certain documents listed in this AD as of October 9, 2013.

**ADDRESSES :**  For service information identified in this AD, contact American Eurocopter Corporation, 2701 N. Forum Drive, Grand Prairie, TX 75052; telephone (972) 641–0000 or (800) 232– 0323; fax (972) 641–3775; or at http:// www.eurocopter.com/techpub. You may review the referenced service information at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. Examining the AD Docket

You may examine the AD docket on the Internet at http:// www.regulations.gov or in person at the Docket Operations Office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the foreignauthority’s AD, any incorporated-byreference service information, the economic evaluation, any comments received, and other information. The street address for the Docket Operations Office (phone: 800–647–5527) is U.S. Department of Transportation, Docket Operations Office, M–30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590.

**FOR FURTHER INFORMATION CONTACT :**  Matt Fuller, Aviation Safety Engineer, Continued Operational Safety, Rotorcraft Directorate, FAA, 2601 Meacham Blvd., Fort Worth, Texas 76137; telephone 817–222–5110; email matthew.fuller@faa.gov

. **SUPPLEMENTARY INFORMATION :** 

Discussion

On March 14, 2013, at 78 FR 16200, the Federal Register published our notice of proposed rulemaking (NPRM), which proposed to amend 14 CFR part 39 to include an AD that would apply to Eurocopter Model AS350B, AS350BA, AS350B1, AS350B2, AS350C, AS350D, AS350D1, AS355E, AS355F, AS355F1, and AS355F2 helicopters with an autopilot installed; Model AS350B3 helicopters with an autopilot or modification 073252 installed; and Model AS355N and AS355NP helicopters with an autopilot or modification 071908 installed. The NPRM proposed to require inspecting the tail rotor control stop screws to determine if they are correctly aligned and adjusting the screws if they are misaligned. The proposed requirements were intended to detect a loose nut or a misaligned stop screw, which, if not corrected, could limit yaw authority, and consequently, result in a loss of helicopter control.

The NPRM was prompted by AD No. 2011–0164, dated August 31, 2011, issued by the European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union. EASA issued AD No. 2011–0164 to correct an unsafe condition for Eurocopter Model AS350B, AS350BA, AS350BB, AS350B1, AS350B2, AS350B3, AS350D, AS355E, AS355F, AS355F1, AS355F2, AS355N, and AS355NP helicopters with either an autopilot or certain modifications installed. EASA advises that during take-off with a sling load, the pilot of a Model AS350B3 helicopter reached one of the yaw stops before its usual position. The inspection that followed revealed that a tail rotor control stop nut was loose and that the corresponding tail rotor control stop screw was ‘‘out of adjustment.’’ EASA states that this condition, if not detected and corrected, ‘‘can lead to the loss of adjustment of the affected stop and consequently limit yaw authority, possibly resulting in loss of control of the helicopter.’’

Comments

After our NPRM (78 FR 16200, March 14, 2013), was published, we received comments from one commenter.
Request

The commenter suggested that an AD is unnecessary because operators should have already tightened the screw.

We disagree that an AD is not needed. More than one tightening of a screw is necessary to correct this unsafe condition. This AD also requires monitoring the stop screws through repetitive inspections to determine whether a screw has become loose. Without these inspections, if a screw becomes loose and is not corrected, yaw authority could be limited, resulting in loss of helicopter control. FAA’s Determination These helicopters have been approved by the aviation authority of France and are approved for operation in the United States. Pursuant to our bilateral agreement with France, EASA, its 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, reviewed the relevant information, considered the comment received, and determined the unsafe condition exists and is likely to exist or develop on other helicopters of these same type designs and that air safety and the public interest require adopting the AD requirements as proposed.

Differences Between this AD and the EASA AD

The EASA AD requires contacting Eurocopter under certain conditions. This does AD not. The EASA AD applies to Eurocopter Model AS350BB helicopters. This AD does not because Model AS350BB does not have an FAA type certificate. However, this AD applies to Eurocopter Model AS350C and AS350D1 helicopters because they have an FAA type certificate and because they have similar tail rotor stop screw assemblies as the other applicable helicopter models. The EASA AD does not apply to the Model AS350C and AS350D1 helicopters.

Interim Action

We consider this AD to be an interim action because Eurocopter is developing a modification to address the unsafe condition identified in this AD. After this modification is developed, approved, and available, we might consider additional rulemaking.

Related Service Information

Eurocopter has issued Alert Service Bulletin (ASB) No. AS350–05.00.64 for Model AS350B, BA, BB, B1, B2, B3, and D civil helicopters and Model AS350L1 military helicopters, and ASB No. AS355–05.00.59 for Model AS355E, F, F1, F2, N, and NP civil helicopters, both Revision 0 and both dated August 30, 2011. The ASBs specify inspecting the locking of the stop screws and, if warranted, adjusting the stops, marking the screw/nut assembly with a red line of paint, and periodically inspecting the paint line’s alignment on the screw/nut assembly. Costs of Compliance

We estimate that this AD will affect 911 helicopters of U.S. Registry and that labor costs average $85 per work-hour.


### 54382 Federal Register / Vol. 78, No. 171 / Wednesday, September 4, 2013 / Rules and Regulations

Based on these estimates, we expect the following costs:

• Inspecting the locking of the stop screws takes about a 0.4 work-hour for a labor cost of about $34 per helicopter and $30,974 for the U.S. fleet. No parts are needed.

• Adjusting the stop screws, if needed, requires about a 0.2 work-hour for a labor cost of $17. No parts are needed.

• Painting the line requires a 0.1 work-hour for a labor cost of about $9 per helicopter and $8,199 for the U.S. fleet. No parts are needed. 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 helicopters identified in this rulemaking action. Regulatory Findings

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);

(3) Will not affect intrastate 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. 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 FAA amends § 39.13 by adding the following new airworthiness directive (AD):

2013–17–01 Eurocopter France Helicopters: Amendment 39–17565; Docket No. FAA–2013–0240; Directorate Identifier 2011–SW–060–AD. (a) Applicability

This AD applies to the following helicopters, certificated in any category:

(1) Model AS350B, AS350BA, AS350B1, AS350B2, AS350C, AS350D, AS350D1, AS355E, AS355F, AS355F1, and AS355F2 helicopters with an autopilot installed;

(2) Model AS350B3 helicopters with an autopilot or modification 073252 installed; and

(3) Model AS355N and AS355NP helicopters with an autopilot or modification 071908 installed.
(b) Unsafe Condition

This AD defines the unsafe condition as a loose nut or misaligned tail rotor control stop screw (stop screw). This condition could result in limited yaw authority and subsequent loss of helicopter control.
(c) Effective Date

This AD becomes effective October 9, 2013.
(d) Compliance

You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
(e) Required Actions

(1) Within 110 hours time-in-service (TIS), inspect the locking of the stop screws to determine whether the stop screws turn.

(i) If any stop screw turns, adjust the stop

screw.

(ii) Mark a line of red paint on the screwnut assembly as depicted in Section B–B, Figure 1 of Eurocopter Alert Service Bulletin (ASB) No. AS350–05.00.64 or ASB No. AS355–05.00.59, as applicable to your model helicopter. Both ASBs are Revision 0 and dated August 30, 2011.

(2) Thereafter, at intervals not to exceed 110 hours TIS, inspect the stop screws to determine whether the paint lines on the screw and the nut are aligned. If the red paint lines are not aligned, remove the paint, adjust the stop screw, and mark a new line of paint on the screw-nut assembly as depicted in Section B–B, Figure 1 of Eurocopter ASB No. AS350–05.00.64 or ASB No. AS355–05.00.59, as applicable to your model helicopter. Both ASBs are Revision 0 and dated August 30,
2011. (f) Special Flight Permits

A one-time flight permit may be granted, provided that the pilot has full yaw authority before flight.
(g) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Safety Management Group, FAA, may approve AMOCs for this AD. Send your proposal to: Matt Fuller, Aviation Safety Engineer, Continued Operational Safety, Rotorcraft Directorate, FAA, 2601 Meacham Blvd., Fort Worth, Texas 76137; telephone 817–222–5110; email matthew.fuller@faa.gov.

(2) For operations conducted under a 14 CFR part 119 operating certificate or under 14 CFR part 91, subpart K, we suggest that you notify your principal inspector, or lacking a principal inspector, the manager of the local flight standards district office or certificate holding district office, before operating any aircraft complying with this AD through an AMOC.
(h) Additional Information

The subject of this AD is addressed in European Aviation Safety Agency (EASA) AD No. 2011–0164, dated August 31, 2011. You may view the EASA AD in the AD Docket on the Internet at http://www.regulations.gov.
(i) Subject

Joint Aircraft Service Component (JASC) Code: 6720, tail rotor control system.
(j) 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 the AD specifies otherwise.

(i) Eurocopter Alert Service Bulletin No. AS350–05.00.64, Revision 0, dated August 30, 2011.

(ii) Eurocopter Alert Service Bulletin No. AS355–05.00.59, Revision 0, dated August 30, 2011.

(3) For Eurocopter service information identified in this AD, contact American Eurocopter Corporation, 2701 N. Forum Drive, Grand Prairie, TX 75052; telephone (972) 641–0000 or (800) 232–0323; fax (972) 641–3775; or at http://www.eurocopter.com/ techpub.

(4) You may view this service information that is incorporated by reference in the AD Docket on the Internet at http:// www.regulations.gov.

(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://


### 54383 Federal Register / Vol. 78, No. 171 / Wednesday, September 4, 2013 / Rules and Regulations

www.archives.gov/federal-register/cfr/ibrlocations.html.

Issued in Fort Worth, Texas, on August 12,
2013. Kim Smith, Directorate Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2013–20238 Filed 9–3–13; 8:45 am]

**BILLING CODE 4910–13–P**

**DEPARTMENT OF TRANSPORTATION**

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2013–0239; Directorate Identifier 2010–SW–087–AD; Amendment**  **39–17552; AD 2013–16–14]**

**RIN 2120–AA64**

**Airworthiness Directives; Eurocopter Deutschland GmbH Helicopters** 

**AGENCY :**  Federal Aviation Administration (FAA), DOT.

**ACTION :**  Final rule.

**SUMMARY :**  We are adopting a new airworthiness directive (AD) for all Eurocopter Deutschland GmbH (ECD) EC 135 P1, P2, P2+, T1, T2, and T2+ helicopters equipped with a certain main transmission housing upper part. This AD requires installing a corrugated washer in the middle of the main transmission filter housing upper part and modifying the main transmission housing upper part. This AD was prompted by an inspection of housing upper parts that revealed the bypass inlet in the oil filter area was not manufactured in accordance with applicable design specifications. The actions of this AD are intended to prevent failure of the main transmission and subsequent loss of control of the helicopter.

**DATES :**  This AD is effective October 9,
2013.

The Director of the Federal Register approved the incorporation by reference of certain documents listed in this AD as of October 9, 2013.

**ADDRESSES :**  For service information identified in this AD, contact American Eurocopter Corporation, 2701 N. Forum Drive, Grand Prairie, TX 75052, telephone (972) 641–0000 or (800) 232– 0323, fax (972) 641–3775, or at http:// www.eurocopter.com/techpub. You may review the referenced service information at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. Examining the AD Docket You may examine the AD docket on the Internet at http:// www.regulations.gov or in person at the Docket Operations Office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the foreignauthority’s AD, any incorporated-byreference service information, the economic evaluation, any comments received, and other information. The street address for the Docket Operations Office (phone: 800–647–5527) is U.S. Department of Transportation, Docket Operations Office, M–30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC 20590.

**FOR FURTHER INFORMATION CONTACT :**  Chinh Vuong, Aviation Safety Engineer, Safety Management Group, Rotorcraft Directorate, FAA, 2601 Meacham Blvd., Fort Worth, Texas 76137; telephone (817) 222–5110; email chinh.vuong@ faa.gov.

**SUPPLEMENTARY INFORMATION :** 

Discussion

On March 14, 2013, at 78 FR 16196, the Federal Register published our notice of proposed rulemaking (NPRM), which proposed to amend 14 CFR part 39 to include an AD that would apply to ECD Model EC135 P1, P2, P2+, T1, T2, and T2+ helicopters with a certain serial numbered main transmission FS108 housing upper part, part number (P/N) 4649 301 034. The NPRM proposed to require installing a corrugated washer in the filter housing of the housing upper part and modifying each affected main transmission housing upper part by machining the oil filter bypass inlet. The proposed requirements were intended to prevent failure of the main transmission and subsequent loss of control of the helicopter.

The NPRM was prompted by AD No. 2010–0213, dated October 14, 2010, issued by the European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union. EASA issued AD No. 2010–0213 to correct an unsafe condition for the ECD model EC 135 and EC635 helicopters. EASA advises that a recent inspection on some housing upper parts for the main transmission FS108 revealed the bypass inlet in the oil filter area had not been manufactured in accordance with the applicable design specifications. EASA advises that this condition, if not detected and corrected, could adversely affect the oil-filter bypass function, which is essential for continued safe flight. The EASA AD requires a temporary modification of the main transmission housing upper part by installing a corrugated washer, and then a ‘‘rework’’ of the oil filter area to bring the affected parts within the applicable design specifications.

Comments

We gave the public the opportunity to participate in developing this AD, but we did not receive any comments on the NPRM (78 FR 16196 March 14, 2013).

FAA’s Determination

These helicopters have been approved by the aviation authority of the Republic of Germany and are approved for operation in the United States. Pursuant to our bilateral agreement with the Republic of Germany, EASA, its 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 exists and is likely to exist or develop on other helicopters of these same type designs and that air safety and the public interest require adopting the AD requirements as proposed.

Related Service Information

ECD has issued Alert Service Bulletin (ASB) ASB EC135–63A–017, Revision 0, dated October 11, 2010 (EC135–63A– 017), which specifies removing the oil filter element and installing a corrugated washer. EC135–63A–017 also specifies reworking the affected filter housing upper part at the next repair or major overhaul of the main transmission, no later than 4,000 flight hours after receipt of the service bulletin. EASA classified this ASB as mandatory and issued AD 2010–0213 to ensure the continued airworthiness of these helicopters.

We have also reviewed ZF Luftfahrttechnik GmbH Service Instruction No. EC135FS108–1659– 1009, dated September 14, 2010, which specifies procedures for repairing the main transmission upper housing, and includes dimensions and tolerances for machining the housing upper part. Costs of Compliance

We estimate that this AD will affect 227 helicopters of U.S. Registry. Based on an average labor rate of $85 per work hour, we estimate that operators may incur the following costs in order to comply with this AD. Installing the corrugated washer will require about .5 work hour, and required parts cost about $10, for a cost per helicopter of about $53, and a total cost to the U.S.