## 31169 Federal Register / Vol. 77, No. 102 / Friday, May 25, 2012 / Rules and Regulations

(g) Pivot Pin Replacement

At the applicable time specified in paragraph 1.E., ‘‘Compliance,’’ of Boeing Alert Service Bulletin 777–55A0018, Revision 1, dated March 6, 2012, except as required by paragraph (i) of this AD: Replace the pivot pins of the horizontal stabilizer with new or reworked pivot pins, including replacing the spacer with a new spacer or with one that has been determined to be without corrosion damage or other irregularities; in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 777–55A0018, Revision 1, dated March 6, 2012.
(h) Repetitive Inspections

At the applicable time specified in paragraph 1.E., ‘‘Compliance,’’ of Boeing Alert Service Bulletin 777–55A0018, Revision 1, dated March 6, 2012: Do detailed inspections for cracks, corrosion damage, or other irregularity of the outer and inner pivot pins; and an ultrasonic inspection for cracking of the outer pivot pins; and do all applicable corrective actions; in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 777–55A0018, Revision 1, dated March 6, 2012. Corrective actions must be done before further flight. Repeat the inspections at the applicable interval specified in paragraph 1.E., ‘‘Compliance,’’ of Boeing Alert Service Bulletin 777–55A0018, Revision 1, dated March 6, 2012.
(i) Exception

Where paragraph 1.E., ‘‘Compliance,’’ of Boeing Alert Service Bulletin 777–55A0018, Revision 1, dated March 6, 2012, specifies a compliance time ‘‘after the Revision 1 date of this service bulletin,’’ this AD requires compliance within the specified compliance time ‘‘after the effective date of this AD.’’
(j) Credit for Previous Actions

This paragraph provides credit for the actions specified in paragraphs (g) and (h) of this AD, if those actions were performed before the effective date of this AD using Boeing Alert Service Bulletin 777–55A0018, dated July 27, 2011.
(k) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Seattle Aircraft Certification Office (ACO), 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 ACO, send it to the attention of the person identified in the Related Information section of this AD. Information may be emailed to: 9-ANMSeattle-ACO-AMOC-Requests@faa.gov.

(2) 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.

(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD if it is approved by the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD.

(l) Related Information

For more information about this AD, contact James Sutherland, Aerospace Engineer, Airframe Branch, ANM–120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, Washington 98057–3356; phone: 425–917–6533; fax: 425– 917–6590; email: james.sutherland@faa.gov.
(m) Material Incorporated by Reference

You must use the following service information to do the actions required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference (IBR) of the following service information under 5 U.S.C. 552(a) and 1 CFR part 51:

(1) Boeing Alert Service Bulletin 777– 55A0018, Revision 1, dated March 6, 2012.

(2) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H–65, Seattle, Washington 98124–2207; telephone 206–544–5000, extension 1; fax 206–766– 5680; email me.boecom@boeing.com; Internet https://www.myboeingfleet.com.

(3) You may review copies of the service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call
425–227–1221.

(4) You may also review copies of the 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.

Issued in Renton, Washington, on May 11,
2012. Michael Kaszycki, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 2012–12087 Filed 5–24–12; 8:45 am]

**BILLING CODE 4910–13–P**



### DEPARTMENT OF TRANSPORTATION

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2012–0251; Directorate Identifier 2012–CE–002–AD; Amendment**  **39–17058; AD 2012–10–09]**

**RIN 2120–AA64**



### Airworthiness Directives; Piper **Aircraft, Inc. Airplanes**

**AGENCY** 

### : Federal Aviation Administration (FAA), DOT. **ACTION** 

### : Final rule.

**SUMMARY** 

### : We are superseding an existing airworthiness directive (AD) for certain Piper Aircraft, Inc. (type certificate previously held by The New Piper Aircraft Inc.) Models PA–31T and PA–31T1 airplanes. That AD currently requires correcting a model identification error on the aircraft data plate. Since we issued that AD, we have become aware that some owner/ operators of the affected airplanes modified the aircraft data plate in error because of confusion in the serial number applicability. Because of the confusion, the manufacturer has issued new service information to clarify affected airplane serial numbers. This new AD requires determining the airplane model based on the serial number and modifying the aircraft data plate to properly identify the airplane model. This new AD also requires doing a detailed search for all applicable airworthiness related documents that apply to any airplane that has an incorrectly marked data plate and take necessary corrective actions based on the search findings. We are issuing this AD to correct the unsafe condition on these products.

**DATES** 

### : This AD is effective June 29,
2012.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in the AD as of June 29, 2012.

**ADDRESSES** 

### : For service information identified in this AD, contact Piper Aircraft, Inc., 926 Piper Drive, Vero Beach, Florida 32960; telephone: (772) 567–4361; Internet: www.piper.com. You may review copies of the referenced service information at the FAA, Small Airplane Directorate, 901 Locust, Kansas City, Missouri 64106. For information on the availability of this material at the FAA, call (816) 329–
4148. Examining the AD Docket

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


## 31170 Federal Register / Vol. 77, No. 102 / Friday, May 25, 2012 / Rules and Regulations

**FOR FURTHER INFORMATION CONTACT** 

### : Gregory ‘‘Keith’’ Noles, Aerospace Engineer, FAA, Atlanta Aircraft Certification Office, 1701 Columbia Avenue, College Park, Georgia 30337; phone: (404) 474–5551; fax: (404) 474– 5606; email: gregory.noles@faa.gov.

**SUPPLEMENTARY INFORMATION** 

### :

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 80–11–06, amendment 39–3776 (45 FR 35309, May 27, 1980). That AD applies to the specified products. The NPRM published in the Federal Register on March 9, 2012 (77 FR 14316). The NPRM proposed to retain all requirements of AD 80–11–06, amendment 39–3776 (45 FR 35309, May 27, 1980) and clarify the serial number applicability of the affected model airplanes. The NPRM also proposed to require a detailed search for all applicable airworthiness related documents that apply to any airplane that has an incorrectly marked aircraft data plate and take necessary corrective actions.

Comments

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM (77 FR 14316, March 9, 2012) or on the determination of the cost to the public.

Conclusion

We reviewed the relevant data and determined that air safety and the public interest require adopting the AD as proposed except for minor editorial changes. We have determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM (77 FR 14316, March 9, 2012) for correcting the unsafe condition; and

• Do not add any additional burden upon the public than was already proposed in the NPRM (77 FR 14316, March 9, 2012).
Costs of Compliance

We estimate that this AD affects 158 airplanes of U.S. registry.

We estimate the following costs to comply with this AD:



### E STIMATED 

### COSTS

Action Labor cost Parts cost Cost per product Cost on U.S. operators

Inspect the aircraft data plate ........ 1 work-hour × $85 per hour = $85 Not applicable ................................ $85 $13,430



### We estimate the following costs to do any necessary modification and/or records search that will be required based on the results of the inspection. We have no way of determining the number of aircraft that might need modification:



### O N 

### -CONDITION 

### COSTS

Action Labor cost Parts cost Cost per product

Modify the aircraft data plate .............................. 1 work-hour × $85 per hour = $85 .... Not applicable .................................... $85 Detailed search for all applicable airworthiness

related documents that apply to any airplane that has an incorrectly marked aircraft data plate. 4 work-hours × $85 per hour = $340 Not applicable .................................... $340



### 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),

(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. 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 removing airworthiness directive (AD) 80–11–06, amendment 39–3776 (45 FR 35309, May 27, 1980), and adding the following new AD:


## 31171 Federal Register / Vol. 77, No. 102 / Friday, May 25, 2012 / Rules and Regulations

2012–10–09 Piper Aircraft, Inc. (Type Certificate Previously Held by The New Piper Aircraft Inc.): Amendment 39– 17058; Docket No. FAA–2012–0251; Directorate Identifier 2012–CE–002–AD.

(a) Effective Date

This airworthiness directive (AD) is effective June 29, 2012.

(b) Affected ADs

This AD supersedes AD 80–11–06, Amendment 39–3776 (45 FR 35309, May 27, 1980).
(c) Applicability

This AD applies to the airplanes identified in paragraphs (c)(1) and (c)(2) of this AD, certificated in any category.

(1) Model PA–31T airplanes, serial numbers 31T–7820001, 31T–7820002, 31T– 7820003, 31T–7820004, 31T–7820005, 31T– 7820006, 31T–7820007, 31T–7820008, 31T– 7820009, 31T–7820010, 31T–7820011, 31T– 7820012, 31T–7820013, 31T–7820014, 31T– 7820015, 31T–7820016, 31T–7820017, 31T– 7820018, 31T–7820019, 31T–7820020, 31T– 7820021, 31T–7820022, 31T–7820023, 31T– 7820024, 31T–7820025, 31T–7820026, 31T– 7820027, 31T–7820028, 31T–7820029, 31T– 7820030, 31T–7820031, 31T–7820032, 31T– 7820033, 31T–7820034, 31T–7820035, 31T– 7820036, 31T–7820037, 31T–7820038, 31T– 7820039, 31T–7820040, 31T–7820041, 31T– 7820042, 31T–7820043, 31T–7820044, 31T– 7820045, 31T–7820046, 31T–7820047, 31T– 7820048, 31T–7820049, 31T–7820050, 31T– 7820051, 31T–7820052, 31T–7820053, 31T– 7820054, 31T–7820055, 31T–7820056, 31T– 7820057, 31T–7820058, 31T–7820059, 31T– 7820060, 31T–7820061, 31T–7820062, 31T– 7820063, 31T–7820064, 31T–7820065, 31T– 7820066, 31T–7820067, 31T–7820068, 31T– 7820069, 31T–7820070, 31T–7820071, 31T– 7820072, 31T–7820073, 31T–7820074, 31T– 7820075, 31T–7820076, 31T–7820077, 31T– 7820078, 31T–7820079, 31T–7820080, 31T– 7820081, 31T–7820082, 31T–7820083, 31T– 7820084, 31T–7820085, 31T–7820086, 31T– 7820087, 31T–7820088, 31T–7820089, 31T– 7820090, 31T–7820091, 31T–7820092; and

(2) Model PA–31T1 airplanes, serial numbers 31T–7804001, 31T–7804002, 31T– 7804003, 31T–7804004, 31T–7804005, 31T– 7804006, 31T–7804007, 31T–7804008, 31T– 7804009, 31T–7804010, 31T–7804011, 31T– 7904001, 31T–7904002, 31T–7904003, 31T– 7904004, 31T–7904005, 31T–7904006, 31T– 7904007, 31T–7904008, 31T–7904009, 31T– 7904010, 31T–7904011, 31T–7904012, 31T– 7904013, 31T–7904014, 31T–7904015, 31T– 7904016, 31T–7904017, 31T–7904018, 31T– 7904019, 31T–7904020, 31T–7904021, 31T– 7904022, 31T–7904023, 31T–7904024, 31T– 7904025, 31T–7904026, 31T–7904027, 31T– 7904028, 31T–7904029, 31T–7904030, 31T– 7904031, 31T–7904032, 31T–7904033, 31T– 7904034, 31T–7904035, 31T–7904036, 31T– 7904037, 31T–7904038, 31T–7904039, 31T– 7904040, 31T–7904041, 31T–7904042, 31T– 7904043, 31T–7904044, 31T–7904045, 31T– 7904046, 31T–7904047, 31T–7904048, 31T– 7904049, 31T–7904050, 31T–7904051, 31T– 7904052, 31T–7904053, 31T–7904056, 31T–
7904057. (d) Subject Joint Aircraft System Component (JASC)/ Air Transport Association (ATA) of America Code 1100, Placards and Markings.

(e) Unsafe Condition

This AD was prompted by reports that some owner/operators of the affected airplanes modified the aircraft data plate in error because of confusion in the serial number applicability. We are issuing this AD to correct the unsafe condition on these products.
(f) Compliance

Comply with this AD within the compliance times specified, unless already done.
(g) Inspect the Aircraft Data Plate

Within the next 100 hours after June 29, 2012 (the effective date of this AD), inspect the markings on the aircraft data plate. Do the inspection following Part I of Piper Aircraft, Inc. Mandatory Service Bulletin No. 1235, dated November 3, 2011.

(1) If the aircraft data plate is correctly marked, make a logbook entry showing compliance with this AD, and no further action is required.

(2) If the aircraft data plate is incorrectly marked, continue with paragraphs (h) and (i) of this AD.
(h) Modify the Aircraft Data Plate

Before further flight after the inspection required in paragraph (g) of this AD, modify the aircraft data plate following Part II of Piper Aircraft, Inc. Mandatory Service Bulletin No. 1235, dated November 3, 2011.

(i) Detailed Aircraft Records Search

Before further flight after the modification required in paragraph (h) of this AD:

(1) Do a detailed search of the aircraft maintenance records and documents to include, but not limited to, ADs, special airworthiness information bulletins (SAIBs), service bulletins (SBs), and other service documents; installed supplemental type certificates (STCs) and parts manufacturing approval (PMAs); and instructions for continued airworthiness (ICAs). Each document found must be assessed to ensure proper actions have been made to maintain airworthiness as affected by the model number of the aircraft. Part 135 operators and other operators utilizing FAA-approved maintenance programs will need to address changes to their inspection programs and related documents.

Note 1 to paragraph (i)(1) of this AD: Although some of the above documents may not be mandatory for compliance, it is still necessary to evaluate them to ensure that any voluntary compliance does not negatively affect the airworthiness of the airplane.

(2) Identify all discrepant conditions for misidentified aircraft and coordinate with the geographic Flight Standards District Office (FSDO) and the Atlanta Aircraft Certification Office (ACO) to determine necessary corrective actions. Also, coordinate with the geographic FSDO to arrange for revisions to the airworthiness certificate, registration, and other potential document/certificate revisions. The following is a list of example discrepant conditions that may be found during the records search:

(i) An AD was complied with that was applicable to the incorrect model, but not applicable to the corrected model.

(ii) A required AD for the corrected model was not complied with.

(iii) A maintenance action was performed that was recommended, but not mandatory, for the incorrect model, but not applicable to the corrected model.

(iv) A PMA part was installed that was applicable for the incorrect model, but not for the corrected model.

(v) An STC was installed that was applicable for the incorrect model, but not for the corrected model.

(vi) An STC was installed that was applicable for both the incorrect and corrected model, but all related, applicable ADs for the corrected model were not complied with.
(j) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Atlanta Aircraft Certification Office (ACO), 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 ACO, send it to the attention of the person identified in the Related Information section of this AD.

(2) 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.

(3) AMOCs approved for AD 80–11–06 (45 FR 35309, May 27, 1980), are approved as AMOCs for this AD.

(k) Related Information

For more information about this AD, contact Gregory ‘‘Keith’’ Noles, Aerospace Engineer, FAA, Atlanta ACO, 1701 Columbia Avenue, College Park, Georgia 30337; phone: (404) 474–5551; fax: (404) 474–5606; email: gregory.noles@faa.gov.
(l) Material Incorporated by Reference

(1) You must use Piper Aircraft, Inc. Mandatory Service Bulletin No. 1235, dated November 3, 2011, to do the actions required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference (IBR) under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) For service information identified in this AD, contact Piper Aircraft, Inc., 926 Piper Drive, Vero Beach, Florida 32960; telephone: (772) 567–4361; Internet: www.piper.com.

(3) You may review copies of the service information at the FAA, Small Airplane Directorate, 901 Locust, Kansas City, Missouri 64106. For information on the availability of this material at the FAA, call (816) 329–4148.

(4) You may also review copies of the service information that is incorporated by reference at the National Archives and


## 31172 Federal Register / Vol. 77, No. 102 / Friday, May 25, 2012 / Rules and Regulations

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. Issued in Kansas City, Missouri, on May 14, 2012. Earl Lawrence, Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 2012–12092 Filed 5–24–12; 8:45 am]

**BILLING CODE 4910–13–P**



### DEPARTMENT OF TRANSPORTATION

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2012–0084; Directorate Identifier 2010–SW–089–AD; Amendment**  **39–17050; AD 2012–10–01]**

**RIN 2120–AA64**



### Airworthiness Directives; Bell **Helicopter Textron Canada Limited Helicopters** 

**AGENCY** 

### : Federal Aviation Administration (FAA), DOT.

**ACTION** 

### : Final rule.

**SUMMARY** 

### : We are adopting a new airworthiness directive (AD) for Bell Helicopter Textron Canada Limited (BHTC) Model 427 helicopters which requires replacing certain tailboom attachment hardware and at certain intervals thereafter, determining the torque of that tailboom attachment hardware. This AD was prompted by a review of the tailboom attachment installation, which revealed that the torque value of the bolts specified in the BHTC Model 427 Maintenance Manual and applied during manufacturing was incorrect and exceeded the torque range recommended for the bolts. The actions are intended to prevent an over-torque of the tailboom attachment bolt (bolt), bolt failure, loss of the tailboom, and subsequent loss of control of the helicopter.

**DATES** 

### : This AD is effective June 29,
2012.

The Director of the Federal Register approved the incorporation by reference of certain documents listed in this AD as of June 29, 2012.

**ADDRESSES** 

### : For service information identified in this AD, contact Bell Helicopter Textron Canada Limited, 12,800 Rue de l’Avenir, Mirabel, Quebec J7J1R4; telephone (450) 437–2862 or (800) 363–8023; fax (450) 433–0272; or
at http://www.bellcustomer.com/files/

. 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, any incorporated-by-reference 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** 

### : Sharon Miles, Aviation Safety Engineer, Regulations and Policy Group, Rotorcraft Directorate, FAA, 2601 Meacham Blvd., Fort Worth, Texas 76137; telephone (817) 222–5110; email sharon.y.miles@faa.gov.

**SUPPLEMENTARY INFORMATION** 

### :

Discussion

On February 3, 2012, at 77 FR 5425, 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 BHTC Model 427 helicopters, serial numbers 56001 through 56084. That NPRM proposed to require within 150 hours time-in-service (TIS) or 90 days, whichever occurs first, the following actions:

• Remove the left upper bolt, washers, and nut. Install the new bolt, part number (P/N) NAS627–27; washers, P/N 140–007–29S25E6 and P/ N NAS1149G0732P; and new nut, P/N 42FLW–720. Run the nut onto the threads of the mating bolt with a torque wrench and measure the existing tare torque. Any bolt and nut used must have a minimum tare torque value of 14 inch/lbs. Torque the nut and coat the bolt head, nut, and washers with appropriate corrosion preventive compound to seal the joint. Repeat these actions at the three remaining bolt locations.

• After installation of the new attachment hardware, at intervals of not less than 1 hour TIS but not exceeding 5 hours TIS, determine the torque of each nut until torque stabilizes at each attachment location. Thereafter, determine the torque of each nut at intervals not to exceed 300 hours TIS.

The proposed requirements were intended to prevent an over-torque of the bolt, bolt failure, loss of the tailboom, and subsequent loss of control of the helicopter.

Transport Canada (TC), which is the aviation authority for Canada, issued Canadian AD CF–2010–32, dated September 30, 2010 (AD CF–2010–32), to correct an unsafe condition for the BHTC Model 427 helicopters, serial numbers (S/Ns) 56001 through 56084, and S/Ns 58001 and 58002. TC advises that a review of the tailboom attachment installation determined that the torque value of the bolts specified in the BHTC Model 427 Maintenance Manual and applied during manufacturing exceeded the torque range recommended for the bolts. They state that this situation, if not corrected, could lead to a bolt failure, detachment of the tailboom, and loss of control of the helicopter.

Comments

We gave the public the opportunity to participate in developing this AD, but we did not receive any comments on the NPRM.

FAA’s Determination

This helicopter model has been approved by the aviation authority of Canada and is approved for operation in the United States. Pursuant to our bilateral agreement with Canada, TC, its technical representative, has notified us of the unsafe condition described in the TC AD. We are issuing this AD because we evaluated all information provided by TC and determined the unsafe condition exists and is likely to exist or develop on other helicopters of this same type design and that air safety and the public interest require adopting the AD requirements as proposed.

Differences Between This AD and the TC AD

The differences between this AD and the TC AD are as follows:

• The TC AD applies to the BHTC Model 427 helicopter, serial numbers 58001 and 58002; however, this AD is not applicable to the BHTC Model 427 helicopters with these serial numbers because they are not eligible for an FAA Certificate of Airworthiness.

Related Service Information

BHTC has issued Alert Service Bulletin No. 427–10–31, dated March 1, 2010 (ASB), which specifies installing new attachment hardware with a reduced torque value. This ASB specifies determining the torque of the newly installed bolts and nuts every 1 to 5 flight hours until torque stabilizes at all locations, and thereafter at intervals not to exceed 300 flight hours. TC classified this ASB as mandatory and issued AD CF–2010–32 to ensure