AD 2007-25-04

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

During scheduled MRB (maintenance review board) mid-life X-ray inspections of Fokker 50 (F27 Mark 050) engine mount frames, severe internal corrosion of the tubes was discovered. In some locations, the depth of the corrosion spots appeared to be more than 50 percent of material thickness. * * * This condition, if not corrected, could ultimately lead to failure of the engine mounting frame in cases where multiple tubes are severely affected. * * *

This AD requires actions that are intended to address the unsafe condition described in the MCAI.

Final rule; request for comments.

2007-25-04 Fokker Services B.V.: Amendment 39-15286. Docket No. FAA- 2007-0268; Directorate Identifier 2007-NM-129-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective December 18, 2007.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Fokker Model F27 Mark 050 airplanes, certificated in any category, all serial numbers, unless the engine mount frames have been inspected previously in accordance with the Fokker 50/60 Maintenance Review Board (MRB) Document, Task Numbers 712000-00-09 and 712000-00-10.

Subject

(d) Air Transport Association (ATA) of America Code 71: Powerplant.

Reason

(e) The mandatory continued airworthiness information (MCAI) states:

During scheduled MRB (maintenance review board) mid-life X-ray inspections of Fokker 50 (F27 Mark 050) engine mount frames, severe internal corrosion of the tubes was discovered. In some locations, the depth of the corrosion spots appeared to be more than 50percent of material thickness. In these cases, Fokker Services advised repair of the affected tubes of the engine mount frames and supplemental inspections. The interior of the tubes and end-fittings of the engine mount frames have been preserved with a film of preservation oil. Premature degradation of this synthetic preservation oil is considered to be the cause of the corrosion. This condition, if not corrected, could ultimately lead to failure of the engine mounting frame in cases where multiple tubes are severely affected. [T]his Airworthiness Directive requires a one- time inspection of the engine mount tubing and end fittings for corrosion, the reporting of the inspection results to Fokker Services and corrective action, as necessary. This is considered to be an interim action; a requirement for a mandatory repetitive inspection will be detailed in a future revision of the MRB document.

The corrective action includes contacting the Civil Aviation Authority--The Netherlands(CAA-NL) (or its designated agent) for repair instructions and repair or replacement of corroded tubes and end fittings of the engine mounting frame.

Actions and Compliance

(f) Unless already done, do the following actions.

(1) Within 24 months after the effective date of this AD, perform an X-ray inspection for corrosion on the engine mount tubing and end fittings, in accordance with the Accomplishment Instructions of Fokker Service Bulletin SBF50-71-047, dated February 15, 2006.

(2) For any engine mount tubing or end fitting found to be outside the corrosion limits specified in Fokker Service Bulletin SBF50-71-047, dated February 15, 2006, during the inspection required by paragraph (f)(1) of this AD, contact the CAA-NL (or its designated agent) for repair instructions and, before further flight, repair or replace the corroded tubing or fitting.

(3) Within 30 days after the accomplishment of the inspection required by paragraph (f)(1) of this AD or within 30 days after the effective date of this AD, whichever occurs later, and in accordance with the procedure described in the Accomplishment Instructions of Fokker Service Bulletin SBF50-71-047, dated February 15, 2006, report all inspection results to the type certificate holder, Fokker Services B.V., Technical Services Dept., P.O. Box 231, 2150 AE Nieuw-Vennep, the Netherlands.

(4) As of 24 months after the effective date of this AD, no spare engine mount may be installed on any aircraft as a replacement part, unless it has been X-ray inspected in accordance with Section 3 of Fokker Component Service Bulletin F8200-035-71-12, dated February 15, 2006, and the engine mount tubing and end fittings have been found to be within the corrosion limits specified in the service bulletin.

FAA AD Differences

Note: This AD differs from the MCAI and/or service information as follows: The MCAI does not specify a corrective action; however, this AD requires contacting the CAA-NL (or its designated agent) for repair instructions, and repair before further flight.

Other FAA AD Provisions

(g) 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. Send information to ATTN: Tom Rodriguez, Aerospace Engineer, International Branch, ANM-116, Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, Washington 98057-3356; telephone (425) 227-1137; fax (425) 227-1149. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.

(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: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act, the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120- 0056.

Related Information

(h) Refer to Mandatory Continuing Airworthiness Information (MCAI) Dutch airworthiness directive NL-2006-005, dated April 13, 2006; Fokker Service Bulletin SBF50-71-047, dated February 15, 2006; and Fokker Component Service Bulletin F8200-035-71-12, dated February 15, 2006; for related information.

Material Incorporated by Reference

(i) You must use Fokker Service Bulletin SBF50-71-047, dated February 15, 2006; to do the actions required by this AD, unless the AD specifies otherwise.

(1) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) For service information identified in this AD, contact Fokker Services B.V., Technical Services Dept., P.O. Box 231, 2150 AE Nieuw-Vennep, the Netherlands.

(3) You may review copies at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or 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 .

Discussion

The Civil Aviation Authority--The Netherlands (CAA-NL), which is the aviation authority for the Netherlands, has issued Dutch airworthiness directive NL-2006-005, dated April 13, 2006 (referred to after this as ``the MCAI''), to correct an unsafe condition for the specified products. The MCAI states:

During scheduled MRB (maintenance review board) mid-life X-ray inspections of Fokker 50 (F27 Mark 050) engine mount frames, severe internal corrosion of the tubes was discovered. In some locations, the depth of the corrosion spots appeared to be more than 50 percent of material thickness. In these cases, Fokker Services advised repair of the affected tubes of the engine mount frames and supplemental inspections. The interior of the tubes and end-fittings of the engine mount frames have been preserved with a film of preservation oil. Premature degradation of this synthetic preservation oil is considered to be the cause of the corrosion. This condition, if not corrected, could ultimately lead to failure of the engine mounting frame in cases where multiple tubes are severely affected. [T]his Airworthiness Directive requires a one- time inspection of the engine mount tubing and end fittings for corrosion, the reporting of the inspection results to Fokker Services and corrective action, as necessary. This is considered to be an interim action; a requirement for a mandatory repetitive inspection will be detailed in a future revision of the MRB document.

The corrective action includes contacting the CAA-NL (or its designated agent) for repair instructions and doing repair or replacement of corroded tubes and end fittings of the engine mounting frame. You may obtain further information by examining the MCAI in the AD docket.

Relevant Service Information

Fokker Services B.V. has issued Fokker Service Bulletin SBF50-71- 047 and Fokker Component Service Bulletin F8200-035-71-12, both dated February 15, 2006. The actions described in this service information are intended to correct the unsafe condition identified in the MCAI.

FAA's Determination and Requirements of This AD

This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of the unsafe condition described in the MCAI and service information referenced above. We are issuing this AD because we evaluated all pertinent information and determined the unsafe condition exists and is likely to exist or develop on other products of the same type design.

There are no products of this type currently registered in the United States. However, this rule is necessary to ensure that the described unsafe condition is addressed if any of these products are placed on the U.S. Register in the future.

Differences Between the AD and the MCAI or Service Information

We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in the MCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information.

We might also have required different actions in this AD from those in the MCAI in order to follow FAA policies. Any such differences are highlighted in a NOTE within the AD.

FAA's Determination of the Effective Date

Since there are currently no domestic operators of this product, notice and opportunity for public comment before issuing this AD are unnecessary.

Comments Invited

This AD is a final rule that involves requirements affecting flight safety, and we did not precede it by notice and opportunity for public comment. We invite you to send any written relevant data, views, or argumentsabout this AD. Send your comments to an address listed under the ADDRESSES section. Include ``Docket No. FAA-2007-0268; Directorate Identifier 2007-NM-129-AD'' at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this AD because 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 we receive about this AD.

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 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); 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 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.

Sec. 39.13 [Amended]

2. The FAA amends Sec. 39.13 by adding the following new AD: