[Federal Register Volume 59, Number 49 (Monday, March 14, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-5852]


[[Page Unknown]]

[Federal Register: March 14, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 93-NM-229-AD]

 

Airworthiness Directives; Fokker Model F27 Series Airplanes 
(Excluding Mark 050 Series Airplanes)

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of Proposed Rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain Fokker Model F27 series 
airplanes. This proposal would require accomplishment of certain 
structural modifications. This proposal is prompted by reports of 
incidents involving fatigue cracking and corrosion in transport 
category airplanes that are approaching or have exceeded their economic 
design goal. These incidents have jeopardized the airworthiness of the 
affected airplanes. The actions specified by the proposed AD are 
intended to prevent degradation in the structural capabilities of the 
affected airplanes. This action also reflects the FAA's decision that 
long term continued operational safety should be assured by actual 
modification of the airframe rather than repetitive inspections.

DATES: Comments must be received by May 9, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 93-NM-229-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9 a.m. and 3 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Fokker Aircraft USA, Inc., 1199 North Fairfax Street, 
Alexandria, Virginia 22314. This information may be examined at the 
FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

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:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications shall identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 93-NM-229-AD.'' The postcard will be date stamped and 
returned to the commenter

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-103, Attention: Rules 
Docket No. 93-NM-229-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    In April 1988, a transport category airplane managed to land after 
tiny cracks in rivet holes in the upper fuselage linked together, 
causing structural failure and explosive decompression. An 18-foot 
section ripped from the fuselage. This accident focused greater 
attention on the problem of aging aircraft.
    In June 1988, the FAA sponsored a conference on aging airplane 
issues, which was attended by representatives of the aviation industry 
from around the world. It became obvious that, because of the 
tremendous increase in air travel, the relatively slow pace of new 
airplane production, and the apparent economic feasibility of operating 
older technology airplanes rather than retiring them, increased 
attention needed to be focused on this aging fleet and maintaining its 
continued operational safety.
    The FAA, in concert with the Regional Airline Association (RAA); 
the General Aviation Manufacturers Association (GAMA); several U.S. and 
non-U.S. operators of the affected airplanes; the Rijksluchtvaartdienst 
(RLD), which is the airworthiness authority for the Netherlands; and 
Fokker; has agreed to undertake the task of identifying and 
implementing procedures to ensure continuing structural airworthiness 
of aging commuter-class airplanes. This group reviewed selected service 
bulletins, applicable to Fokker Model F27 series airplanes, to be 
recommended for mandatory rulemaking action to ensure the continued 
operational safety of these airplanes.
    This group's proposal is contained in Fokker Report Number SE-278, 
``F27 Aging Aircraft Project-Final Document,'' Issue 3, dated February 
1, 1993. This Report references modifications from eight service 
bulletins and recommends that they be incorporated in the applicable 
Fokker Model F27 series airplanes. The modifications consist of three 
modifications to the fuselage, two modifications to the wing, and three 
modifications to the empennage of the airplane. They include structural 
reinforcement of frames, ribs, and stringers; replacement of formers 
and ribs; and installation of inspection doors and covers, access 
holes, and drain holes.
    The procedures described in these service bulletins are intended to 
positively address conditions identified in Model F27 series airplanes 
that, if not corrected, could result in structural failure.
    The RLD classified this Report as mandatory and issued Netherlands 
Airworthiness Directive (BLA) 91-058/5 (A), dated July 16, 1993, in 
order to assure the continued airworthiness of these airplanes in the 
Netherlands.
    This airplane model is manufactured in the Netherlands and is type 
certificated for operation in the United States under the provisions of 
Sec. 21.29 of the Federal Aviation Regulations and the applicable 
bilateral airworthiness agreement. Pursuant to this bilateral 
airworthiness agreement, the RLD has kept the FAA informed of the 
situation described above. The FAA has examined the findings of the 
RLD, reviewed all available information, and determined that AD action 
is necessary for products of this type design that are certificated for 
operation in the United States.
    Since fatigue cracking and corrosion are likely to exist or develop 
on other airplanes of the same type design registered in the United 
States, the proposed AD would require modification of Fokker Model F27 
series airplanes prior to their economic design goal in accordance with 
the Fokker Report described previously.
    The economic design goal of an airplane is typically considered to 
be the period of service after which a substantial increase in the 
maintenance costs is expected to take place in order to assure 
continued operational safety. The economic design goal for Fokker Model 
F27 series airplanes is 90,000 landings for structural problems 
associated with fatigue damage.
    The proposed compliance time for implementation of the mandatory 
structural modification program is prior to reaching the applicable 
economic design goal. This time interval was determined based upon the 
ability of the manufacturer to provide the parts necessary for the 
modification, and the time necessary to incorporate the modifications.
    In the interim, safety will be provided by various means currently 
in place that are considered satisfactory to detect damage prior to the 
occurrence of an unsafe condition. These include operators' on-going 
basic maintenance programs; continuing inspections required by numerous 
previously issued AD's; the Structural Integrity Program (SIP) program, 
previously mandated by AD 92-19-07, Amendment 39-8365 (57 FR 42693, 
September 16, 1992); the FAA's increased emphasis on surveillance of 
operators' maintenance programs and procedures; and the FAA's 
participation in programs to physically inspect high-time airplanes 
during scheduled heavy maintenance.
    The FAA estimates that 58 Fokker Model F27 series airplanes 
(excluding Mark 050 series airplanes) of U.S. registry would be 
affected by this proposed AD within the initial threshold. Since not 
all affected airplanes would be required to accomplish every 
modification referenced in each of the service bulletins, the cost 
impact of the proposed modifications is estimated in the following 
table. This cost includes the price of modification kits, and the 
estimated labor rate is $55 per work hour. It does not include the cost 
of downtime, planning, set up, familiarization, or tool acquisition.

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                                      No. of                                                      Total cost for
      Service Bulletin No.           affected       No. of work    Cost of parts     Cost per        affected   
                                    airplanes         hours        per airplane      airplane        airplanes  
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55-33 (B-77)....................               5           40               $314       $2,514.00      $12,570.00
55-12 (B-67)....................               5           20                121        1,221.00        6,105.00
55-12 (Part II).................               5           30                168        1,818.00        9,090.00
55-61 Revision 2................              13           45              2,235        4,710.00       61,230.00
57-68 Revision 1................              58          556              1,279       31,859.00    1,847,822.00
53-19 (B-45) Issue 3............               5           22                  0        1,210.00        6,050.00
53-58 (B-149)...................               5           16                  0          880.00        4,400.00
53-76 (B-211)...................              13            0.25               0           13.75          178.75
57-7 Issue 1....................               5           32                400        2,160.00       10,800.00
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    Based on these figures, above, the total cost impact of the 
proposed AD on U.S. operators is estimated to be $1,958,245.75.
    The total cost impact figure discussed above is based on 
assumptions that no operator has yet accomplished any of the proposed 
requirements of this AD action, and that no operator would accomplish 
those actions in the future if this AD were not adopted.
    The FAA recognizes that the proposed modifications would require a 
large number of work hours to accomplish. However, the threshold 
specified in each of the service bulletins referenced by the Fokker 
Report should allow ample time for the accomplishment of the 
modifications coincidentally with scheduled major airplane inspection 
and maintenance activities, thereby minimizing the costs associated 
with special airplane scheduling.
    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this proposed 
regulation: (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) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 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:

Fokker: Docket 93-NM-229-AD.

    Applicability: Model F27 series airplanes (excluding Mark 050 
series airplanes), as listed in Fokker Report Number SE-278, ``F27 
Aging Aircraft Project--Final Document,'' Issue 3, dated February 1, 
1993; certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent structural failure, accomplish the following:
    (a) Prior to reaching the incorporation thresholds listed in 
Part II of Fokker Report Number SE-278, ``F27 Aging Aircraft 
Project--Final Document,'' Issue 3, dated February 1, 1993, 
accomplish the structural modifications listed in Part II of the 
Fokker Report.

    Note 1: The modifications required by this paragraph do not 
terminate the inspection requirements of any other AD unless that AD 
specifies that any such modification constitutes terminating action 
for that inspection requirement.

    (b) 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 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.

    (c) 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.

    Issued in Renton, Washington, on March 8, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-5852 Filed 3-11-94; 8:45 am]
BILLING CODE 4910-13-U