Airworthiness Directives; Fokker Model F.28 Mark 0070 and Mark 0100 Airplanes

[Federal Register Volume 73, Number 104 (Thursday, May 29, 2008)]
[Rules and Regulations]
[Pages 30749-30752]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E8-11501]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0231; Directorate Identifier 2007-NM-218-AD; 
Amendment 39-15534; AD 2008-11-12]
RIN 2120-AA64


Airworthiness Directives; Fokker Model F.28 Mark 0070 and Mark 
0100 Airplanes

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

ACTION: Final rule.

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SUMMARY: 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:

    To date, there have been at least 10 reported events on Fokker 
70 (F28 Mark 0070) and Fokker 100 (F28 Mark 0100) aircraft where the 
flight crew manually overpowered the autopilot, inadvertently 
neglecting to disengage the autopilot. * * * When the autopilot is 
not disengaged, the elevator servomotor is overpowered and the 
horizontal stabilizer is moved by the Automatic Flight Control & 
Augmentation System (AFCAS) auto-trim in a direction opposite to the 
(manual) deflection of the elevator, causing high elevator control 
forces. This condition, if not corrected, could cause the stabilizer 
to move to an extreme out-of-trim position, creating the (remote) 
possibility of loss of control of the aircraft, due to the extreme 
control loads.

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

DATES: This AD becomes effective July 3, 2008.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of July 3, 
2008.

ADDRESSES: You may examine the AD docket on the Internet at http://www.regulations.gov or in person at the U.S. Department of 
Transportation, Docket Operations, M-30, West Building Ground Floor, 
Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC.

FOR FURTHER INFORMATION CONTACT: 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.

SUPPLEMENTARY INFORMATION:

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 March 3, 2008 (73 FR 
11366). That NPRM proposed to correct an unsafe condition for the 
specified products. The MCAI states:

    To date, there have been at least 10 reported events on Fokker 
70 (F28 Mark 0070) and Fokker 100 (F28 Mark 0100) aircraft where the 
flight crew manually overpowered the autopilot, inadvertently 
neglecting to disengage the autopilot. Detailed investigation of 
these incidents has shown that this usually occurs in a high 
workload environment that demands immediate manual control of the 
aircraft by the pilot flying, e.g. terrain warning. When the 
autopilot is not disengaged, the elevator servomotor is overpowered 
and the horizontal stabilizer is moved by the

[[Page 30750]]

Automatic Flight Control & Augmentation System (AFCAS) auto-trim in 
a direction opposite to the (manual) deflection of the elevator, 
causing high elevator control forces. This condition, if not 
corrected, could cause the stabilizer to move to an extreme out-of-
trim position, creating the (remote) possibility of loss of control 
of the aircraft, due to the extreme control loads. In the original 
design of AFCAS, operation of the control wheel-mounted stabilizer 
trim switches has no effect when the autopilot is engaged. Based on 
the assumption that stabilizer trim switches will be operated by the 
pilot flying when encountering high control forces, an Autopilot 
Disconnect Unit has been developed that disconnects the autopilot 
when the stabilizer trim switches are operated. Since a potentially 
unsafe condition has been identified that may exist or develop on 
aircraft of this type design, this Airworthiness Directive requires 
the installation of Autopilot Disconnect Units and associated wiring 
changes.

    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.

Correction to Table Information

    We have corrected the date of Fokker Drawing W46143, Sheet 03, 
Issue K, to March 7, 2002, in Table 1 of this AD.

Conclusion

    We reviewed the available data and determined that air safety and 
the public interest require adopting the AD with the change described 
previously. We determined that this change will not increase the 
economic burden on any operator or increase the scope of the AD.

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 about 12 products of U.S. 
registry. We also estimate that it will take about 27 work-hours per 
product to comply with the basic requirements of this AD. The average 
labor rate is $80 per work-hour. Required parts will cost about $3,000 
per product. Where the service information lists required parts costs 
that are covered under warranty, we have assumed that there will be no 
charge for these parts. As we do not control warranty coverage for 
affected parties, some parties may incur costs higher than estimated 
here. Based on these figures, we estimate the cost of this AD to the 
U.S. operators to be $61,920, or $5,160 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 
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.

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

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

2008-11-12 Fokker Services B.V.: Amendment 39-15534. Docket No. FAA-
2008-0231; Directorate Identifier 2007-NM-218-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective July 3, 
2008.

Affected ADs

    (b) None.

Applicability

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

Subject

    (d) Air Transport Association (ATA) of America Code 22: Auto 
flight.

Reason

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

    To date, there have been at least 10 reported events on Fokker 
70 (F28 Mark 0070) and Fokker 100 (F28 Mark 0100) aircraft where the 
flight crew manually overpowered the autopilot, inadvertently 
neglecting to disengage the autopilot. Detailed investigation of 
these incidents has shown that this usually occurs in a high 
workload environment that demands immediate manual control of the 
aircraft by the pilot flying, e.g. terrain warning. When the 
autopilot is not disengaged, the elevator

[[Page 30751]]

servomotor is overpowered and the horizontal stabilizer is moved by 
the Automatic Flight Control & Augmentation System (AFCAS) auto-trim 
in a direction opposite to the (manual) deflection of the elevator, 
causing high elevator control forces. This condition, if not 
corrected, could cause the stabilizer to move to an extreme out-of-
trim position, creating the (remote) possibility of loss of control 
of the aircraft, due to the extreme control loads. In the original 
design of AFCAS, operation of the control wheel-mounted stabilizer 
trim switches has no effect when the autopilot is engaged. Based on 
the assumption that stabilizer trim switches will be operated by the 
pilot flying when encountering high control forces, an Autopilot 
Disconnect Unit has been developed that disconnects the autopilot 
when the stabilizer trim switches are operated. Since a potentially 
unsafe condition has been identified that may exist or develop on 
aircraft of this type design, this Airworthiness Directive requires 
the installation of Autopilot Disconnect Units and associated wiring 
changes.

Actions and Compliance

    (f) Within 36 months after the effective date of this AD, unless 
already done, install autopilot disconnect units and do associated 
wiring changes in accordance with Section 3, ``Accomplishment 
Instructions,'' of Fokker Service Bulletin SBF100-22-050, dated 
April 25, 2006, including the drawings listed in Table 1 of this AD.

                      Table 1.--Drawings Included in Fokker Service Bulletin SBF100-22-050
----------------------------------------------------------------------------------------------------------------
            Fokker drawing                  Sheet               Issue                         Date
----------------------------------------------------------------------------------------------------------------
W41501...............................             057  CQ.....................  April 25, 2006.
W41501...............................             058  CQ.....................  April 25, 2006.
W41501...............................             059  CQ.....................  April 25, 2006.
W41501...............................             060  CQ.....................  April 25, 2006.
W41501...............................             061  CR.....................  April 25, 2006.
W41501...............................             062  CR.....................  April 25, 2006.
W41504...............................             009  K......................  April 25, 2006.
W41504...............................             010  K......................  April 25, 2006.
W41504...............................             011  J......................  April 25, 2006.
W41504...............................             012  L......................  April 25, 2006.
W41504...............................             013  L......................  April 25, 2006.
W46140...............................              27  AR.....................  March 5, 2002.
W46140...............................              28  AR.....................  March 8, 2002.
W46143...............................              02  K......................  February 26, 2002.
W46143...............................              03  K......................  March 7, 2002.
W46144...............................              06  R......................  March 4, 2002.
W46144...............................              07  S......................  March 7, 2002.
W46912...............................              01  D......................  March 12, 2002.
W46930...............................              01  Original...............  March 14, 2002.
W46930...............................              02  E......................  March 14, 2002.
W46932...............................              01  D......................  March 13, 2002.
W59140...............................             177  GC.....................  February 8, 2006.
W59140...............................             178  GB.....................  February 6, 2006.
W59140...............................             221  GB.....................  February 6, 2006.
----------------------------------------------------------------------------------------------------------------

FAA AD Differences

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

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, FAA, 
Transport Airplane Directorate, 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 MCAI Dutch Airworthiness Directive NL-2006-010, 
dated July 14, 2006; and Fokker Service Bulletin SBF100-22-050, 
dated April 25, 2006, including the drawings listed in Table 1 of 
this AD, for related information.

Material Incorporated by Reference

    (i) You must use Fokker Service Bulletin SBF100-22-050, dated 
April 25, 2006, including the drawings specified in Table 2 of this 
AD, to do the actions required by this AD, unless the AD specifies 
otherwise.

                      Table 2.--Drawings Included in Fokker Service Bulletin SBF100-22-050
----------------------------------------------------------------------------------------------------------------
            Fokker drawing                  Sheet               Issue                         Date
----------------------------------------------------------------------------------------------------------------
W41501...............................             057  CQ.....................  April 25, 2006.
W41501...............................             058  CQ.....................  April 25, 2006.
W41501...............................             059  CQ.....................  April 25, 2006.
W41501...............................             060  CQ.....................  April 25, 2006.
W41501...............................             061  CR.....................  April 25, 2006.
W41501...............................             062  CR.....................  April 25, 2006.
W41504...............................             009  K......................  April 25, 2006.
W41504...............................             010  K......................  April 25, 2006.

[[Page 30752]]

 
W41504...............................             011  J......................  April 25, 2006.
W41504...............................             012  L......................  April 25, 2006.
W41504...............................             013  L......................  April 25, 2006.
W46140...............................              27  AR.....................  March 5, 2002.
W46140...............................              28  AR.....................  March 8, 2002.
W46143...............................              02  K......................  February 26, 2002.
W46143...............................              03  K......................  March 7, 2002.
W46144...............................              06  R......................  March 4, 2002.
W46144...............................              07  S......................  March 7, 2002.
W46912...............................              01  D......................  March 12, 2002.
W46930...............................              01  Original...............  March 14, 2002.
W46930...............................              02  E......................  March 14, 2002.
W46932...............................              01  D......................  March 13, 2002.
W59140...............................             177  GC.....................  February 8, 2006.
W59140...............................             178  GB.....................  February 6, 2006.
W59140...............................             221  GB.....................  February 6, 2006.
----------------------------------------------------------------------------------------------------------------

    (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.

    Issued in Renton, Washington, on May 14, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E8-11501 Filed 5-28-08; 8:45 am]
BILLING CODE 4910-13-P

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