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Proposed Rule

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

Document Details

Information about this document as published in the Federal Register.

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Start Preamble

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for all Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes equipped with certain crew seat bucket assemblies with and without a backrest recline system. This proposed AD would require you to replace the backrest tubes on these crew seat bucket assemblies at a specified time and adds a life limit for these backrest tubes. This proposed AD results from mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. We are issuing this proposed AD to prevent cracks in the backrest tubes of certain crew seat bucket assemblies, which could result in failure of the seat system. This failure could lead to the pilot and co-pilot's reduced ability to control the airplane. This failure could also affect the proper function of the seat restrain system in the case of an emergency landing.

DATES:

We must receive comments on this proposed AD by March 16, 2006.

ADDRESSES:

Use one of the following addresses to comment on this proposed AD:Start Printed Page 7699

  • DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
  • Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
  • Mail: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC 20590.
  • Fax: 1-202-493-2251.
  • Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Contact Pilatus Aircraft Ltd., Customer Support Manager, CH-6371 Stans, Switzerland; telephone: +41 41 619 6208; facsimile: +41 41 619 7311; or Pilatus Business Aircraft Ltd., Product Support Department, 11755 Airport Way, Broomfield, Colorado 80021; telephone: (303) 465-9099; facsimile: (303) 465-6040 for the service information identified in this proposed AD.

You may examine the comments on this proposed AD in the AD docket on the Internet at http://dms.dot.gov.

Start Further Info

FOR FURTHER INFORMATION CONTACT:

Doug Rudolph, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4059; facsimile: (816) 329-4090.

End Further Info End Preamble Start Supplemental Information

SUPPLEMENTARY INFORMATION:

Comments Invited

How do I comment on this proposed AD? We invite you to send any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include the docket number, “FAA-2004-19220; Directorate Identifier 2004-CE-27-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this proposed rulemaking. Using the search function of the DOT docket Web site, anyone can find and read the comments received into any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78) or you may visit http://dms.dot.gov.

Examining the Dockets

Where can I go to view the docket information? You may examine the docket that contains the proposal, any comments received and any final disposition on the Internet at http://dms.dot.gov, or in person at the DOT Docket Offices between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Office (telephone 1-800-647-5227) is located on the plaza level of the Department of Transportation Nassif Building at the street address stated in ADDRESSES. Comments will be available in the AD docket shortly after the Docket Management Facility receives them.

Discussion

What events have caused this proposed AD? The Federal Office for Civil Aviation (FOCA), which is the airworthiness authority for Switzerland, notified FAA that an unsafe condition may exist on all Pilatus Models PC-12 and PC-12/45 airplanes equipped with certain crew seat bucket assemblies with and without a backrest recline system. The FOCA reports that during a regular maintenance inspection, the seat bucket assembly tubes on a crew seat with a recline system had failed.

Fatigue on the left-hand (LH) and right-hand (RH) seat bucket assembly tubes at the location of the energy device pins caused the seat bucket assembly tubes to fail. The lower tubes were attached but the upper tubes were completely detached.

Pilatus conducted further investigation to determine if additional crew seat bucket assembly backrest tubes have fatigue cracks.

Thirty-one of the affected airplanes were inspected. Six pilot and two co-pilot seats were found with partial fatigue cracks. None had completely failed. The cracks were found on the backrest tubes of the crew seat bucket assemblies with the recline feature.

The result of the inspections led to the establishment of a life limit for the backrest tubes on certain crew seat bucket assemblies with and without a backrest recline system.

What is the potential impact if FAA took no action? If not prevented, cracks in the backrest tubes of the seat bucket assembly could cause the seat system to fail. This failure could lead to the pilot and co-pilot's reduced ability to control the airplane. This failure could also affect the proper function of the seat system in the case of an emergency landing.

Is there service information that applies to this subject? Pilatus has issued Pilatus PC12 Maintenance Manual Temporary Revision No. 04-13, dated June 15, 2005.

What are the provisions of this service information? The maintenance manual temporary revision establishes a life limit for the backrest tubes on crew seat bucket assemblies with and without a recline system.

What action did the FOCA take? The FOCA classified this maintenance manual temporary revision as mandatory and issued Swiss AD Number HB-2005-470, Effective Date: December 30, 2005, to ensure the continued airworthiness of these airplanes in Switzerland.

Did the FOCA inform the United States under the bilateral airworthiness agreement? These Pilatus Models PC-12 and PC-12/45 airplanes are manufactured in Switzerland and are type-certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement.

Under this bilateral airworthiness agreement, the FOCA has kept us informed of the situation described above.

FAA's Determination and Requirements of This Proposed AD

What has FAA decided? We have examined the FOCA's findings, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Since the unsafe condition described previously is likely to exist or develop on other Pilatus Models PC-12 and PC-12/45 airplanes of the same type design that are registered in the United States, we are proposing AD action to prevent cracks in the backrest tubes of certain crew seat bucket assemblies, which could result in failure of the seat system. This failure could lead to the pilot and co-pilot's reduced ability to control the airplane. This failure could also affect the proper function of the seat restrain system in the case of an emergency landing.

FAA's Determination and Requirements of the Proposed AD

Why have we determined AD action is necessary and what would this Start Printed Page 7700proposed AD require? We are proposing this AD to address an unsafe condition that we determined is likely to exist or develop on other products of this same type design. The proposed AD would require you to replace the backrest tubes on certain crew seat bucket assemblies at a specified time and adds a life limit for the backrest tubes.

Costs of Compliance

How many airplanes would this proposed AD impact? We estimate that this proposed AD affects 260 airplanes in the U.S. registry.

What would be the cost impact of this proposed AD on owners/operators of the affected airplanes? We estimate the following costs to accomplish this proposed replacement:

Labor costParts costTotal cost per seat bucket assemblyTotal cost on U.S. operators
3 work hours × $65 per hour = $195 per seat bucket assembly$600 per seat bucket assembly. 2 seats on each airplane$195 + $600 = $795 per seat bucket assembly$795 per seat bucket assembly × 2 per airplane = $1,590. $1,590 × 260 = $413,400.

Authority for This Rulemaking

What authority does FAA have for issuing this rulemaking action? 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

Would this proposed AD impact various entities? We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 the proposed regulation:

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); and

3. 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 a regulatory evaluation of the estimated costs to comply with this proposed AD. See the ADDRESSES section for a location to examine the regulatory evaluation.

Start List of Subjects

List of Subjects in 14 CFR Part 39

End List of Subjects

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 14 CFR part 39 as follows:

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PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

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Authority: 49 U.S.C. 106(g), 40113, 44701.

End Authority
[Amended]

2. The Federal Aviation Administrator amends § 39.13 by adding the following new airworthiness directive (AD):

Pilatus Aircraft LTD.: Docket No. FAA-2004-19220; Directorate Identifier 2004-CE-27-AD.

When Is the Last Date I Can Submit Comments on This Proposed AD?

(a) The Federal Aviation Administration (FAA) must receive comments on this proposed AD action by March 16, 2006.

What Other ADs Are Affected by This Action?

(b) None.

What Airplanes Are Affected by This AD?

(c) This AD affects all Models PC-12 and PC-12/45 airplanes that are equipped with the following crew seat bucket assemblies and are certificated in any category:

(1) Crew seats with a recline system, part numbers (P/N): 959.30.01.111, 959.30.01.112, 959.30.01.121, and 959.30.01.122.

(2) Crew seats without recline system, P/Ns: 959.30.01.131, 959.30.01.132, 959.30.01.133, and 959.30.01.134.

What Is the Unsafe Condition Presented in This AD?

(d) This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified in this AD are intended to prevent cracks in the backrest tubes of certain crew seat bucket assemblies, which could result in failure of the seat system. This failure could lead to the pilot and co-pilot's reduced ability to control the airplane. This failure could also affect the proper function of the seat restrain system in the case of an emergency landing.

What Must I Do To Address This Problem?

(e) To address this problem, you must do the following:

ActionsComplianceProcedures
(1) For crew seat bucket assemblies with a recline system, part numbers (P/N) 959.30.01.111, 959.30.01.112, 959.30.01.121, and 959.30.01.122 (or FAA-approved equivalent P/Ns), replace the backrest tubesInitially replace upon the accumulation of 5,000 hours time-in-service (TIS) or within the next 100 hours TIS after the effective date of this AD, whichever occurs later. Thereafter, replace the backrest tubes upon the accumulation of 5,000 hours TIS (the life limit established in this AD)As specified in Pilatus PC12 Maintenance Manual Temporary Revision No. 04-13, dated June 15, 2005. Replace following the procedures in the applicable component maintenance manual. (CMM)
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(2) For crew seat bucket assemblies without a recline system, P/Ns 959.30.01.131, 959.30.01.132, 959.30.01.133, and 959.30.01.134 (or FAA-approved equivalent P/Ns), replace the backrest tubesInitially replace upon the accumulation of 10,000 hours TIS or within the next 100 hours TIS after the effective date of this AD, whichever occurs later. Thereafter, replace the backrest tubes upon the accumulation of 10,000 hours TIS (the life limit established in this AD)As specified in Pilatus PC12 Maintenance Manual Temporary Revision No. 04-13, dated June 15, 2005. Replace following the procedures in the CMM.
(3) Do not install:
(i) Any crew seat bucket assembly with a recline system, P/N 959.30.01.111, 959.30.01.112, 959.30.01.121, and 959.30.01.122 (or FAA-approved equivalent P/Ns), with unknown hours TIS or which has accumulated 5,000 or more hours TIS; orAs of the effective date of this AD. The life limits specified in paragraphs (e)(1) and (e)(2) of this AD apply to all parts installed as sparesNot Applicable.
(ii) Any crew seat bucket assembly without a recline system, P/N 959.30.01.131, 959.30.01.132, 959.30.01.133, and 959.30.01.134 (or FAA-approved equivalent P/Ns), with unknown hours TIS or which has accumulated 10,000 or more hours TIS.
(4) 14 CFR 21.303 allows for replacement parts through parts manufacturer approval (PMA). The phrase “or FAA-approved equivalent part number” in this AD is intended to signify those parts that are PMA parts approved through identicality to the design of the part under the type certificate and replacement parts to correct the unsafe condition under PMA (other than identicality). If parts are installed that are identical to the unsafe parts, then the corrective actions of the AD affect these parts also. In addition, equivalent replacement parts to correct the unsafe condition under PMA (other than identicality) may also be installed provided they meet current airworthiness standards, which include those actions cited in this ADNot ApplicableNot Applicable.
(5) You must contact the type certificate holder any time a modification or repair is done that affects the parts listed in paragraphs (e)(1), (e)(2), and (e)(3) of this AD to determine the effect, if any, the modification or repair may have on the life limits established in this ADAs of the effective date of this ADNot Applicable.

Note:

Return all replaced backrest tubes to Pilatus Aircraft Ltd., Structural Analysis Group ECE, Ch-6371 Stans, Switzerland. Include the following information: crew seat P/N and serial number, aircraft manufacturer serial number, aircraft flying hours, number of flights, and replacement date of the replaced backrest tubes.

May I Request an Alternative Method of Compliance?

(f) The Manager, Standards Office, Small Airplane Directorate, FAA, has the authority to approve alternative methods of compliance for this AD, if requested using the procedures found in 14 CFR 39.19. For information on any already approved alternative methods of compliance or for information pertaining to this AD, contact Doug Rudolph, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4059; facsimile: (816) 329-4090.

Is There Other Information That Relates to This Subject?

(g) Swiss AD Number HB-2005-470, Effective Date: December 30, 2005, also addresses the subject of this AD.

May I Get Copies of the Documents Referenced in This AD?

(h) To get copies of the documents referenced in this AD, contact Pilatus Aircraft Ltd., Customer Support Manager, CH-6371 Stans, Switzerland; telephone: +41 41 619 6208; facsimile: +41 41 619 7311; or Pilatus Business Aircraft Ltd., Product Support Department, 11755 Airport Way, Broomfield, Colorado 80021; telephone: (303) 465-9099; facsimile: (303) 465-6040. To view the AD docket, go to the Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC, or on the Internet at http://dms.dot.gov. The docket number is Docket No. FAA-2004-19220; Directorate Identifier 2004-CE-27-AD.

Start Signature

Issued in Kansas City, Missouri, on February 7, 2006.

Steven W. Thompson,

Acting Manager, Small Airplane Directorate, Aircraft Certification Service.

End Signature End Part End Supplemental Information

[FR Doc. E6-2020 Filed 2-13-06; 8:45 am]

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