AD 2010-22-05

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:

When preparing for landing, the flight crew of a F28 Mark 0100 (Fokker 100) aeroplane observed a main landing gear (MLG) unsafe indication after landing gear down selection. * * * [T]he right (RH) MLG was partly extended and the left (LH) MLG door was open but without the MLG being extended. * * *

Subsequent investigation revealed that the cause of the MLG extension problem was the (partially) blocked hydraulic return line from the MLG selector valve by pieces of hard plastic. These were identified as parts of the poppet seat of PBSOV [parking brake shut- off valve] Part Number (P/N) 70379. * * *

This condition, if not detected and corrected, could lead to further events where the MLG fails to extend, possibly resulting in loss of control of the aeroplane during landing.

* * * * *

We are issuing this AD to require actions to correct the unsafe condition on these products.

Final rule.

2010-22-05 Fokker Services B.V.: Amendment 39-16484. Docket No. FAA- 2010-0516; Directorate Identifier 2009-NM-251-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective December 3, 2010.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Fokker Services B.V. Model F.28 Mark 0070 and 0100 airplanes, certificated in any category, all serial numbers.

Subject

(d) Air Transport Association (ATA) of America Code 32: Landing Gear.

Reason

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

When preparing for landing, the flight crew of a F28 Mark 0100 (Fokker 100) aeroplane observed a main landing gear (MLG) unsafe indication after landing gear down selection. * * * [T]he right (RH) MLG was partly extended and the left (LH) MLG door was open but without the MLG being extended. * * *

Subsequent investigation revealed that the cause of the MLG extension problem was the (partially) blocked hydraulic return line from the MLG selector valve by pieces of hard plastic. These were identified as parts of the poppet seat of PBSOV [parking brake shut- off valve] Part Number (P/N) 70379. * * *

This condition, if not detected and corrected, could lead to further events where the MLG fails to extend, possibly resulting in loss of control of the aeroplane during landing.

* * * * *

Compliance

(f) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Actions

(g) Do the following actions.

(1) Within 30 days after the effective date of this AD, do a detailed inspection of the hydraulic lines associated with the PBSOV for contamination in the system (the presence of pieces of material from the poppet seat of an unmodified PBSOV having P/N 70379). If any contamination is found, before further flight, remove the contamination, in accordance with Part 1 of the Accomplishment Instructions of Fokker Service Bulletin SBF100-32-159, dated October 6, 2009.

(2) Within 18 months after the effective date of this AD, re- inspect the hydraulic lines and do all applicable corrective actions as required by paragraph (g)(1) of this AD, and replace the unmodified PBSOV having P/N 70379, with a modified PBSOV having P/N 70379 having the suffix "A'' behind the serial number on the identification plate, in accordance with Part 2 of the Accomplishment Instructions of Fokker Service Bulletin SBF100-32- 159, dated October 6, 2009.

(3) After accomplishing paragraph (g)(2) of this AD, do not install any unmodified PBSOV having P/N 70379, unless the PBSOV having P/N 70379 has been modified, having the suffix "A'' behind the serial number on the identification plate, in accordance with the Accomplishment Instructions of Eaton Service Bulletin 70379-32- 01, dated September 15, 2001.

FAA AD Differences

Note 1: This AD differs from the MCAI and/or service information as follows: No differences.

Other FAA AD Provisions

(h) 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 principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards 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: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120-0056.

Related Information

(i) Refer to MCAI European Aviation Safety Agency Airworthiness Directive 2009-0220, dated October 14, 2009; Fokker Service Bulletin SBF100-32-159, dated October 6, 2009; and Eaton Service Bulletin 70379-32-01, dated September 15, 2001; for related information.

Material Incorporated by Reference

(j) You must use Fokker Service Bulletin SBF100-32-159, dated October 6,2009; and Eaton Service Bulletin 70379-32-01, dated September 15, 2001; as applicable; 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; telephone +31 (0)252-627-350; fax +31 (0)252-627-211; e-mail technicalservices.fokkerservices@stork.com; Internet http:// www.myfokkerfleet.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/code_of_federal_regulations/ ibr_locations.html.

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to the specified products. That NPRM was published in the Federal Register on May 18, 2010 (75 FR 27668). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI states:

When preparing for landing, the flight crew of a F28 Mark 0100 (Fokker 100) aeroplane observed a main landing gear (MLG) unsafe indication after landing gear down selection. The approach was aborted and the landing gear unsafe procedure was accomplished. As this did not produce the desired effect, a low pass was performed and the control tower confirmed that the right (RH) MLG was partly extended and the left (LH) MLG door was open but without the MLG being extended. Eventually the aeroplane landed with partly extended landing gear, without resulting in serious injuries to the occupants.

Subsequent investigation revealed that the cause of the MLG extension problem was the (partially) blocked hydraulic return line from the MLG selector valve by pieces of hard plastic. These were identified as parts of the poppet seat of PBSOV [parking brake shut- off valve] Part Number (P/N) 70379. The PBSOV installed on the incident aeroplane was a modified version of P/N 70379, identified by suffix "A'' behind the serial number on the identification plate. This modification was introduced by Eaton, the valve manufacturer, with Eaton Service Bulletin (SB) 70379-32-01 and includes replacement of the original poppet with clamped hard plastic seat by an improved poppet assembly with screwed-on seat. When the affected valve was opened, it was confirmed that it contained the improved poppet assembly. The poppet seat fragments found in the return system therefore originated from a previously installed (pre SB 70379-32-01) P/N 70379 PBSOV and must have been present in the return/pressure line prior to installation of the modified PBSOV.

This condition, if not detected and corrected, could lead to further events where the MLG fails to extend, possibly resulting in loss of control of the aeroplane during landing.

For the reasons described above, this [EASA] AD requires the [detailed] inspection of the associated hydraulic lines, irrespective what type PBSOV is installed, removal of contamination in the system, if any, and replacement of each unmodified PBSOV with a modified unit. This [EASA] AD also prohibits, after installation of a modified PBSOV on an aeroplane, re-installation of an unmodified PBSOV on that aeroplane.

You may obtain further information by examining the MCAI in the AD docket.

Comments

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM or on the determination of the cost to the public.

Conclusion

We reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed.

Differences Between This 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 our FAA policies. Any such differences are highlighted in a NOTE within the AD.

Costs of Compliance

We estimate that this AD will affect 6 products of U.S. registry. We also estimate that it will take about 4 work-hours per product to comply with the basic requirements of this AD. The average labor rate is $85 per work-hour. Based on these figures, we estimate the cost of this AD to the U.S. operators to be$2,040, or $340 per product.

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 underExecutive 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.

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 the NPRM, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone (800) 647-5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

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: