AD 2006-25-06

final rule

Airworthiness Directives; Fokker Model F27 Mark 500 Airplanes

AD Number
2006-25-06
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2006-25086
FR Citation
71 FR 71475
Technical illustration of an aircraft landing gear and wheel assembly
Problem area Landing gear

Applicability

TypeManufacturerModelDetails
aircraft Fokker Services F27 Mark 500 Airworthiness Directives; Fokker Model F27 Mark 500 Airplanes

Unsafe Condition

Fatigue cracking from an improperly machined radius of the inner tube in certain main landing gear (MLG) drag stay units (DSUs), which could lead to DSU failure and collapse of the MLG during landing.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Inspect to determine whether certain MLG DSUs are installed. Perform an ultrasonic inspection to determine if certain tubes are installed in the affected DSUs. Take investigative/corrective actions if necessary.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before further flight

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

All Fokker Model F27 Mark 500 airplanes.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

The FAA is adopting a new airworthiness directive (AD) for all Fokker Model F27 Mark 500 airplanes. This AD requires an inspection to determine whether certain main landing gear (MLG) drag stay units (DSUs) are installed. This AD also requires an ultrasonic inspection to determine if certain tubes are installed in the affected DSUs of the MLG, and related investigative/corrective actions if necessary. This AD results from a report that, due to fatigue cracking from an improperly machined radius of the inner tube, a drag stay broke, and, consequently, led to the collapse of the MLG during landing. We are issuing this AD to prevent such fatigue cracking, which could result in reduced structural integrity or collapse of the MLG.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 71, Number 237 (Monday, December 11, 2006)]
[Rules and Regulations]
[Pages 71475-71478]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: E6-20861]


=======================================================================
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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-25086; Directorate Identifier 2006-NM-019-AD; 
Amendment 39-14847; AD 2006-25-06]
RIN 2120-AA64


Airworthiness Directives; Fokker Model F27 Mark 500 Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all 
Fokker Model F27 Mark 500 airplanes. This AD requires an inspection to 
determine whether certain main landing gear (MLG) drag stay units 
(DSUs) are installed. This AD also requires an ultrasonic inspection to 
determine if certain tubes are installed in the affected DSUs of the 
MLG, and related investigative/corrective actions if necessary. This AD 
results from a report that, due to fatigue cracking from an improperly 
machined radius of the inner tube, a drag stay broke, and, 
consequently, led to the collapse of the MLG during landing. We are 
issuing this AD to prevent such fatigue cracking, which could result in 
reduced structural integrity or collapse of the MLG.

DATES: This AD becomes effective January 16, 2007.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in the AD as of January 16, 
2007.

ADDRESSES: You may examine the AD docket on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a> or in person at the Docket Management Facility, U.S. 
Department of Transportation, 400 Seventh Street, SW., Nassif Building, 
Room PL-401, Washington, DC.
    Contact Fokker Services B.V., P.O. Box 231, 2150 AE Nieuw-Vennep, 
the Netherlands, for service information identified in this AD.

FOR FURTHER INFORMATION CONTACT: Tom Rodriguez, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 
227-1137; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: 

Examining the Docket

    You may examine the airworthiness directive (AD) docket on the 
Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a> or in person at the Docket Management 
Facility office between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The Docket Management Facility office 
(telephone (800) 647-5227) is located on the plaza level of the Nassif 
Building at the street address stated in the ADDRESSES section.

Discussion

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to include an AD that would apply to all Fokker Model F27 
Mark 500 airplanes. That NPRM was published in the Federal Register on 
June 21, 2006 (71 FR 35572). That NPRM proposed to require an 
inspection to determine whether certain main landing gear (MLG) drag 
stay units (DSUs) are installed. That NPRM also proposed to require an 
ultrasonic inspection to determine if certain tubes are installed in 
the affected DSUs of the MLG, and related investigative/corrective 
actions if necessary.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comment received.

Request To Change Incorporation of Certain Information

    The Modification and Replacement Parts Association (MARPA) states 
that, typically, airworthiness directives are based on service 
information originating with the type certificate holder or its 
suppliers. MARPA adds that manufacturer service documents are privately 
authored instruments generally having copyright protection against 
duplication and distribution. MARPA notes that when a service document 
is incorporated by reference into a public document, such as an 
airworthiness directive, it loses its private, protected status and 
becomes a public document. MARPA adds that if a service document is 
used as a mandatory element of compliance, it should not simply be 
referenced, but should be incorporated into the regulatory document; by 
definition, public laws must be public, which means they cannot rely 
upon private writings.
    MARPA adds that incorporated by reference service documents should 
be made available to the public by publication in the Docket Management 
System (DMS), keyed to the action that incorporates them. MARPA notes 
that the stated purpose of the incorporation by reference method is 
brevity, to keep from expanding the Federal Register needlessly by 
publishing documents already in the hands of the affected individuals; 
traditionally, ``affected individuals'' means aircraft owners and 
operators, who are generally provided service information by the 
manufacturer. MARPA adds that a new class of affected individuals has 
emerged, since the majority of aircraft maintenance is now performed by 
specialty shops instead of aircraft owners and operators. MARPA notes 
that this new class includes maintenance and repair organizations, 
component servicing and repair shops, parts purveyors and distributors, 
and organizations manufacturing or servicing alternatively certified 
parts under section 21.303 (``Replacement and modification parts'') of 
the Federal Aviation Regulations (14 CFR 21.303). MARPA adds that the 
concept of brevity is now nearly archaic as documents exist more 
frequently in electronic format than on paper. Therefore, MARPA asks 
that the service documents deemed essential to the accomplishment of 
the NPRM be incorporated by reference into the regulatory instrument, 
and published in the DMS.

[[Page 71476]]

    We do not agree that documents should be incorporated by reference 
during the NPRM phase of rulemaking. The Office of the Federal Register 
(OFR) requires that documents that are necessary to accomplish the 
requirements of the AD be incorporated by reference during the final 
rule phase of rulemaking. This final rule incorporates by reference the 
document necessary for the accomplishment of the requirements mandated 
by this AD. Further, we point out that while documents that are 
incorporated by reference do become public information, they do not 
lose their copyright protection. For that reason, we advise the public 
to contact the manufacturer to obtain copies of the referenced service 
information.
    In regard to the commenter's request that service documents be made 
available to the public by publication in the Federal Register, we 
agree that incorporation by reference was authorized to reduce the 
volume of material published in the Federal Register and the Code of 
Federal Regulations. However, as specified in the Federal Register 
Document Drafting Handbook, the Director of the OFR decides when an 
agency may incorporate material by reference. As the commenter is 
aware, the OFR files documents for public inspection on the workday 
before the date of publication of the rule at its office in Washington, 
DC. As stated in the Federal Register Document Drafting Handbook, when 
documents are filed for public inspection, anyone may inspect or copy 
file documents during the OFR's hours of business. Further questions 
regarding publication of documents in the Federal Register or 
incorporation by reference should be directed to the OFR.
    In regard to the commenter's request to post service bulletins on 
the Department of Transportation's DMS, we are currently in the process 
of reviewing issues surrounding the posting of service bulletins on the 
DMS as part of an AD docket. Once we have thoroughly examined all 
aspects of this issue and have made a final determination, we will 
consider whether our current practice needs to be revised. No change to 
the final rule is necessary in response to this comment.

Conclusion

    We have carefully reviewed the available data, including the 
comment received, and determined that air safety and the public 
interest require adopting the AD as proposed.

Costs of Compliance

    The following table provides the estimated costs for U.S. operators 
to comply with this AD.

                                                                     Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                        Number of U.S.-
                               Action                                   Work hours     Average labor       Cost per        registered       Fleet cost
                                                                                       rate per hour       airplane        airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Inspection.........................................................               2              $80             $160                7           $1,120
--------------------------------------------------------------------------------------------------------------------------------------------------------

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); 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. See the ADDRESSES 
section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The Federal Aviation Administration (FAA) amends Sec.  39.13 by 
adding the following new airworthiness directive (AD):

2006-25-06 Fokker Services B.V.: Amendment 39-14847. Docket No. FAA-
2006-25086; Directorate Identifier 2006-NM-019-AD.

Effective Date

    (a) This AD becomes effective January 16, 2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to all Fokker Model F27 Mark 500 airplanes, 
certificated in any category.

Unsafe Condition

    (d) This AD results from a report that, due to fatigue cracking 
from an improperly machined radius of the inner tube, a drag stay 
broke, and, consequently, led to the collapse of the main landing 
gear (MLG) during landing. We are issuing this AD to prevent such 
fatigue cracking, which could result in reduced structural integrity 
or collapse of the MLG.

Compliance

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

[[Page 71477]]

Inspections of the Drag Stay Units

    (f) Within 60 days after the effective date of this AD: Inspect 
the MLG drag stay units (DSUs) to determine whether Dowty Aerospace 
is the manufacturer and, before further flight, inspect Dowty 
Aerospace MLG DSUs to determine whether part number (P/N) 200261001, 
200261002, 200485001, 200485002, 200684001, or 200684002 is 
installed. A review of the airplane maintenance records is 
acceptable in lieu of these inspections if the manufacturer and the 
part number of the MLG DSU can be conclusively determined from that 
review. For airplanes equipped with MLG DSUs other than Dowty 
Aerospace MLG DSUs, and for airplanes equipped with Dowty Aerospace 
MLG DSUs having part numbers other than P/N 200261001, 200261002, 
200485001, 200485002, 200684001, and 200684002, no further action is 
required by this AD, except as specified in paragraph (k) of this 
AD.
    (g) For airplanes equipped with DSUs having P/N 200261001, 
200485001, or 200684001: Within 60 days after the effective date of 
this AD, perform an ultrasonic inspection to determine if a tube 
having P/N 200485300 with a straight bore, or a tube having P/N 
200259300 with a change in section (stepped bore), is installed on 
the DSUs of the MLG, in accordance with the Accomplishment 
Instructions of Fokker Service Bulletin F27/32-171, dated December 
16, 2004.

    Note 1:  Fokker Service Bulletin F27/32-171, dated December 16, 
2004, refers to Dowty Aerospace Landing Gear Service Bulletin 32-
82W, Revision 2, including Appendix A, dated July 29, 1994, and 
including Appendix B, Revision 1, dated November 10, 1993; and Dowty 
Aerospace Landing Gear Service Bulletin 32-169B, Revision 2, 
including Appendix A, dated July 29, 1994, and including Appendix B, 
Revision 1, dated November 10, 1993; as applicable, as appropriate 
sources of service information for inspecting MLG DSUs.

    (h) If any tube having P/N 200485300 with a straight bore is 
found installed during the inspection required by paragraph (g) of 
this AD: Before further flight, re-identify the DSU with P/N 
200261004, 200485004, or 200684004, in accordance with the 
Accomplishment Instructions of Dowty Aerospace Landing Gear Service 
Bulletin 32-82W, Revision 2, including Appendix A, dated July 29, 
1994, and including Appendix B, Revision 1, dated November 10, 1993; 
or Dowty Aerospace Landing Gear Service Bulletin 32-169B, Revision 
2, including Appendix A, dated July 29, 1994, and including Appendix 
B, Revision 1, dated November 10, 1993; as applicable. After re-
identifying the DSU, no further action is required by this AD for 
that DSU; however airplanes are still subject to the requirements 
specified in paragraph (k) of this AD.
    (i) If any tube having P/N 200259300 with a change in section 
(stepped bore) is found installed during the inspection required by 
paragraph (g) of this AD: Before further flight, re-identify the DSU 
in accordance with paragraphs 2.A.(4)(a) and 2.A.(4)(b) of the 
Accomplishment Instructions of Dowty Aerospace Landing Gear Service 
Bulletin 32-82W, Revision 2, including Appendix A, dated July 29, 
1994, and including Appendix B, Revision 1, dated November 10, 1993; 
or Dowty Aerospace Landing Gear Service Bulletin 32-169B, Revision 
2, including Appendix A, dated July 29, 1994, and including Appendix 
B, Revision 1, dated November 10, 1993; as applicable. Following 
accomplishment of the re-identification, before further flight, do 
the inspection specified in paragraph (j) of this AD.

Ultrasonic Inspection for Cracking

    (j) For airplanes equipped with re-identified DSUs having P/N 
200261002, 200485002, 200684002, 200261003, 200485003, or 200684003: 
Within 60 days after the effective date of this AD, perform an 
ultrasonic inspection to detect cracking in the re-identified DSUs, 
in accordance with the Accomplishment Instructions of Dowty 
Aerospace Landing Gear Service Bulletin 32-82W, Revision 2, 
including Appendix A, dated July 29, 1994, and including Appendix B, 
Revision 1, dated November 10, 1993; or Dowty Aerospace Landing Gear 
Service Bulletin 32-169B, Revision 2, including Appendix A, dated 
July 29, 1994, and including Appendix B, Revision 1, dated November 
10, 1993; as applicable.
    (1) For airplanes equipped with any DSU re-identified as P/N 
200684003, 200261003, or 200485003: If no crack is detected, no 
further action is required by this AD for that DSU; however 
airplanes are still subject to the requirements specified in 
paragraph (k) of this AD.
    (2) For airplanes equipped with any DSU re-identified as P/N 
200684002, 200261002, or 200485002: If no crack is detected, do the 
actions specified in paragraphs (j)(2)(i) and (j)(2)(ii) of this AD.
    (i) Repeat the ultrasonic inspection required by paragraph (j) 
of this AD thereafter at intervals not to exceed 1,500 flight cycles 
until the actions specified in paragraph (j)(2)(ii) of this AD are 
done.
    (ii) At the next MLG overhaul but no later than 12,000 flight 
cycles after the effective date of this AD, rework and re-identify 
the DSU as P/N 200261003, 200485003, or 200684003, as applicable, in 
accordance with the applicable service bulletin.
    (3) If any crack is detected and the crack signal indication of 
any DSU tube is greater than or equal to 80 percent, before further 
flight, replace the DSU with a re-identified DSU having P/N 
200261004, 200485004, 200684004, 200261003, 200485003, or 200684003, 
in accordance with the applicable service bulletin.
    (4) If any crack is detected and the crack signal indication of 
any DSU tube is greater than zero percent but less than 80 percent, 
do the actions specified in paragraphs (j)(4)(i) and (j)(4)(ii) of 
this AD.
    (i) Repeat the ultrasonic inspection required by paragraph (j) 
of this AD thereafter at intervals not to exceed 1,500 flight cycles 
until the actions specified in paragraph (j)(4)(ii) of this AD are 
done.
    (ii) At the next MLG overhaul but no later than 12,000 flight 
cycles after the effective date of this AD, replace the DSU with a 
DSU having P/N 200261004, 200485004, 200684004, 200261003, 
200485003, or 200684003, in accordance with the applicable service 
bulletin.

Parts Installation

    (k) As of the effective date of this AD, no person may install a 
MLG DSU, P/N 200261001, 200261002, 200485001, 200485002, 200684001, 
or 200684002, on any airplane, except as specified in paragraph (i) 
of this AD.

Alternative Methods of Compliance (AMOCs)

    (l)(1) The Manager, International Branch, ANM-116, Transport 
Airplane Directorate, FAA, has the authority to approve AMOCs for 
this AD, if requested in accordance with the procedures found in 14 
CFR 39.19.
    (2) Before using any AMOC approved in accordance with Sec.  
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

Related Information

    (m) Dutch airworthiness directive NL-2005-003, dated April 29, 
2005, also addresses the subject of this AD.

Material Incorporated by Reference

    (n) You must use the applicable service bulletin listed in Table 
1 of this AD to perform the actions that are required by this AD, 
unless the AD specifies otherwise.

              Table 1.--Material Incorporated by Reference
------------------------------------------------------------------------
      Service Bulletin         Revision level             Date
------------------------------------------------------------------------
Dowty Aerospace Landing Gear  2...............  July 29, 1994.
 Service Bulletin 32-169B,
 Revision 2, including
 Appendix A, dated July 29,
 1994, and including
 Appendix B, Revision 1,
 dated November 10, 1993.
Dowty Aerospace Landing Gear  2...............  July 29, 1994.
 Service Bulletin 32-82W,
 Revision 2, including
 Appendix A, dated July 29,
 1994, and including
 Appendix B, Revision 1,
 dated November 10, 1993.
Fokker Service Bulletin F27/  Original........  December 16, 2004.
 32-171.
------------------------------------------------------------------------


[[Page 71478]]

    Dowty Aerospace Landing Gear Service Bulletin 32-169B, Revision 
2, including Appendix A, dated July 29, 1994, and including Appendix 
B, Revision 1, dated November 10, 1993, contains the following 
effective pages:

------------------------------------------------------------------------
                               Revision level
           Page No.             shown on page      Date shown on page
------------------------------------------------------------------------
1............................  2.............  July 29, 1994.
2, 3.........................  Original......  September 10, 1993.
4............................  1.............  November 10, 1993.
------------------------------------------------------------------------
                               Appendix A
------------------------------------------------------------------------
1, 5, 7......................  2.............  July 29, 1994.
2, 6.........................  Original......  September 10, 1993.
3, 4.........................  1.............  November 10, 1993.
------------------------------------------------------------------------
                               Appendix B
------------------------------------------------------------------------
1-5..........................  1.............  November 10, 1993.
------------------------------------------------------------------------

    Dowty Aerospace Landing Gear Service Bulletin 32-82W, Revision 
2, including Appendix A, dated July 29, 1994, and including Appendix 
B, Revision 1, dated November 10, 1993, contains the following 
effective pages:

------------------------------------------------------------------------
                               Revision level
           Page No.             shown on page      Date shown on page
------------------------------------------------------------------------
1............................  2.............  July 29, 1994
2, 3.........................  Original......  September 10, 1993.
4............................  1.............  November 10, 1993.
------------------------------------------------------------------------
                               Appendix A
------------------------------------------------------------------------
1, 5, 7......................  2.............  July 29, 1994.
2, 6.........................  Original......  September 10, 1993.
3, 4.........................  1.............  November 10, 1993.
------------------------------------------------------------------------
                               Appendix B
------------------------------------------------------------------------
1-5..........................  1.............  November 10, 1993.
------------------------------------------------------------------------
------------------------------------------------------------------------

    The Director of the Federal Register approved the incorporation 
by reference of these documents in accordance with 5 U.S.C. 552(a) 
and 1 CFR part 51. Contact Fokker Services B.V., P.O. Box 231, 2150 
AE Nieuw-Vennep, the Netherlands, for a copy of this service 
information. You may review copies at the Docket Management 
Facility, U.S. Department of Transportation, 400 Seventh Street, 
SW., Room PL-401, Nassif Building, Washington, DC; on the Internet 
at <a href="http://dms.dot.gov">http://dms.dot.gov</a>; or at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at the NARA, call (202) 741-6030, or go to <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.

    Issued in Renton, Washington, on November 24, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E6-20861 Filed 12-8-06; 8:45 am]
BILLING CODE 4910-13-P

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