[Federal Register Volume 59, Number 76 (Wednesday, April 20, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-9340]


[[Page Unknown]]

[Federal Register: April 20, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 93-NM-165-AD; Amendment 39-8885; AD 94-08-13]

 

Airworthiness Directives; Fokker Model F-28 Mark 0100 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Fokker Model F-28 Mark 0100 series airplanes, 
that requires the installation of modified Flight Warning Computers and 
Flight Augmentation Computers. This amendment is prompted by reports of 
nuisance yaw-damper fault warnings and undetected horizontal trim 
motion, and the development of improved computers that eliminate these 
problems. The actions specified by this AD are intended to prevent 
nuisance warnings in the cockpit and undetected trim motion, both of 
which could compromise the safe takeoff of the airplane.

DATES: Effective May 20, 1994.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 20, 1994.

ADDRESSES: The service information referenced in this AD may be 
obtained from Fokker Aircraft USA, Inc., 1199 North Fairfax Street, 
Alexandria, Virginia 22314. This information may be examined at the 
Federal Aviation Administration (FAA), Transport Airplane Directorate, 
Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the 
Office of the Federal Register, 800 North Capitol Street, NW., suite 
700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Mark Quam, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone (206) 
227-2145; fax (206) 227-1320.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations to include an airworthiness directive (AD) that is 
applicable to certain Fokker Model F-28 Mark 0100 series airplanes was 
published in the Federal Register on November 12, 1993 (58 FR 59968). 
That action proposed to require the installation of modified Flight 
Warning Computers (FWC) and Flight Augmentation Computers (FAC).
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.
    One commenter supports the proposed rule.
    Another commenter requests that the proposed rule be revised to 
include an additional part-numbered FWC as an acceptable alternative 
part for compliance. This commenter states that it has installed FWC's 
having part number 80-0610-3-31, in accordance with Fokker Service 
Bulletin SBF100-31-033, dated June 23, 1993, on its fleet of affected 
airplanes. The FAA has reviewed this data and finds that FWC's having 
part number 80-0610-3-31 are acceptable alternatives to those called 
out in the proposal. The FAA has revised the final rule to indicate 
that this.
    This same commenter requests that the proposed rule be revised to 
include the words ``or subsequent'' for all part numbers, so that 
future designs of the components would be permitted to be installed as 
alternatives to the specific part numbered components called out in the 
AD. The FAA does not concur, since there would be no way to establish 
that the inclusion of these words would prevent the installation of 
incompatible components. For example, the ``Material Information'' 
portion of the referenced Fokker Service Bulletin SBF100-22-037, 
concerning the replacement of FAC's, indicates that specific equipment 
combinations (those having similar part numbers in the component 
series) may not be compatible. For this reason, the FAA considers it 
inappropriate to permit the indiscriminate installation of any future 
component designs.
    This same commenter requests that the proposed rule not require 
accomplishment of the actions specifically in accordance with the 
service bulletins; the service bulletins should be for reference only. 
Although the commenter does not specify a particular reason for this 
request, the FAA infers that (1) the commenter would like to install 
improved or modified equipment versions of the same basic part number 
series that may or may not be called out in a service bulletin; or (2) 
the commenter would prefer that the rule permit installation of the 
subject components in accordance with an operator's own methods. The 
FAA does not concur. As for the first inference, the FAA has addressed 
this in the previous paragraph. As for the second inference, the FAA 
points out that the referenced service bulletins contain specific 
wiring procedures necessary for installation of the components; the FAA 
has determined that these procedures must be followed in order to 
ensure proper installation.
    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the change previously 
described. The FAA has determined that this change will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.
    The FAA estimates that 27 airplanes of U.S. registry will be 
affected by this AD.
    Installation of the new FWC will require approximately 46 work 
hours to accomplish, at an average labor charge of $55 per work hour. 
Required parts will cost approximately $450 per airplane. Based on 
these figures, the total cost impact of the FWC installation on U.S. 
operators is estimated to be $2,980 per airplane.
    The requirement to replace the FAC will vary, depending upon the 
configuration of the FAC installed. Additionally, operators have a 
choice of two different FAC's to use as replacement installations:
    Should an operator elect to install an FAC having part number 622-
7478-401MOD11, it will require approximately 1 work hour to accomplish, 
at an average labor charge of $55 per work hour. Required parts will be 
provided at no cost to the operator. Based on these figures, the total 
cost impact of this specific installation requirement on U.S. operators 
would be $55 per airplane.
    Should an operator elect to install an FAC having part number 622-
7478-411, it will require approximately 52 work hours to accomplish, at 
an average labor charge of $55 per work hour. Required parts will cost 
approximately $2,515 per airplane. Based on these figures, the total 
cost impact of this specific FAC installation requirement on U.S. 
operators is estimated to be $5,375 per airplane.
    Based on the figures discussed above, the total cost impact of this 
proposed AD on U.S. operators would be between $3,005 and $8,355 per 
airplane, or between $81,135 and $225,585 for the entire U.S. fleet.
    The total cost impact figures discussed above are based on 
assumptions that no operator has yet accomplished any of the 
requirements of this AD action, and that no operator would accomplish 
those actions in the future if this AD were not adopted. However, the 
FAA has been advised that at least one U.S. operator affected by the AD 
has previously accomplished the required installations on most of its 
fleet of airplanes. In light of this, the total future cost impact of 
the rule is expected to be less than the figures indicated above.
    The regulations adopted herein will not have substantial direct 
effects 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. Therefore, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this action (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. A final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from the Rules Docket at the location provided under the caption 
ADDRESSES.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 14 CFR part 
39 of the Federal Aviation Regulations as follows:

PART 39--AIRWORTHINESS DIRECTIVES

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

    Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

94-08-13 Fokker: Amendment 39-8885. Docket 93-NM-165-AD.

    Applicability: Model F-28 Mark 0100 series airplanes; serial 
numbers 11244 through 11348, inclusive; equipped with Flight Warning 
Computer, P/N 80-0610-2-( ); or equipped with Flight Augmentation 
Computer, part number (P/N) 622-7478-321 or P/N 622-7478-401; 
certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent nuisance yaw-damper fault warnings and undetected 
trim motion, accomplish the following:
    (a) For airplanes having serial numbers 11244 through 11321 
inclusive, 11323 through 11329 inclusive, 11331, and 11333; and 
equipped with Flight Warning Computer (FWC) P/N 80-0610-2-( ): 
Within one year after the effective date of this AD, remove the 
currently installed FWC, modify the airplane, and install FWC P/N 
80-0610-3-30, in accordance with Fokker Service Bulletin SBF100-31-
020, Revision 1, dated June 12, 1993.

    Note 1: Installation accomplished prior to the effective date of 
this AD in accordance with Fokker Service Bulletin SBF100-31-020, 
dated May 24, 1991, is considered to be in compliance with this 
paragraph.
    Note 2: Installation of FWC P/N 80-0610-3-31, in accordance with 
Fokker Service Bulletin SBF100-31-031, dated June 23, 1993, is 
considered an acceptable alternative method of compliance with this 
paragraph.

    (b) For airplanes having serial numbers 11244 through 11339 
inclusive, 11341, and 11342; and equipped with Flight Augmentation 
Computer (FAC) P/N 622-7478-321: At the same time as, or prior to 
further flight after, accomplishing the requirements of paragraph 
(a) of this AD, remove the currently installed FAC and replace it 
with either of the following:
    (1) FAC P/N 622-7478-401MOD11, in accordance with Fokker Service 
Bulletin SBF100-22-032, dated September 2, 1991; or
    (2) FAC P/N 622-7478-411, in accordance with Fokker Service 
Bulletin SBF100-22-037, dated May 31, 1993. Equipment combinations 
listed in that service bulletin must be adhered to.
    (c) For airplanes having serial numbers 11244 through 11348 
inclusive, and equipped with FAC P/N 622-7478-401: Within one year 
after the effective date of this AD, remove the currently installed 
FAC and replace it with either of the following:
    (1) FAC P/N 622-7478-401MOD11, in accordance with Fokker Service 
Bulletin SBF100-22-032, dated September 2, 1991; or
    (2) FAC P/N 622-7478-411, in accordance with Fokker Service 
Bulletin SBF100-22-037, dated May 31, 1993. Equipment combinations 
listed in that service bulletin must be adhered to.
    (d) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Standardization Branch, ANM-113, 
FAA, Transport Airplane Directorate. Operators shall submit their 
requests through an appropriate FAA Principal Maintenance Inspector, 
who may add comments and then send it to the Manager, 
Standardization Branch, ANM-113.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.

    (e) Special flight permits may be issued in accordance with 
Federal Aviation Regulations (FAR) 21.197 and 21.199 to operate the 
airplane to a location where the requirements of this AD can be 
accomplished.
    (f) The installations shall be done in accordance with Fokker 
Service Bulletin SBF100-22-032, dated September 2, 1991; Fokker 
Service Bulletin SBF100-22-037, dated May 31, 1993, and Fokker 
Service Bulletin SBF100-31-020, Revision 1, dated June 12, 1993, 
which contains the following list of effective pages:

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                                       Revision level     Date shown on 
              Page No.                  shown on page         page      
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1, 2, 5-12, 17, 19A, 19B, 22-24, 32,  1...............  June 12, 1993.  
 34, 36.                                                                
3, 4, 13-16, 18, 19, 20, 21, 25-31,   Original........  May 24, 1991.   
 33, 35.                                                                
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This incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Copies may be obtained from Fokker Aircraft USA, Inc., 1199 
North Fairfax Street, Alexandria, Virginia 22314. Copies may be 
inspected at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the Office of the Federal 
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
    (g) This amendment becomes effective on May 20, 1994.

    Issued in Renton, Washington, on April 13, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-9340 Filed 4-19-94; 8:45 am]
BILLING CODE 4940-13-U