[Federal Register Volume 62, Number 104 (Friday, May 30, 1997)]
[Proposed Rules]
[Pages 29308-29309]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-14183]



[[Page 29308]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-NM-174-AD]
RIN 2120-AA64


Airworthiness Directives; Fokker F28 Mark 1000, 2000, 3000, and 
4000 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 all Fokker Model F28 Mark 1000, 
2000, 3000, and 4000 series airplanes. This proposal would require a 
one-time visual inspection of the rear cargo door and luggage auxiliary 
structure for corrosion, repetitive borescope inspections of the rear 
cargo door, and removal and repair of any corrosion found during the 
inspections. This proposal would also require the drilling of drain 
holes and application of a corrosion preventive and sealing compound 
inside the rear cargo door, and modification of the rear cargo door to 
aid in future routine borescope inspections. This proposal is prompted 
by reports of corrosion being found in the affected areas on several of 
the affected airplanes. The actions specified by the proposed AD are 
intended to prevent such corrosion, which could result in structural 
failure of the cargo door and loss of the door during flight, and 
consequent rapid decompression, aerodynamic instability, and/or damage 
to other fuselage structures.

DATES: Comments must be received by July 11, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 96-NM-174-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 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: Tim Dulin, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2141; fax (425) 227-1149.

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 96-NM-174-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. 96-NM-174-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Rijksluchtvaartdienst (RLD), which is the airworthiness 
authority for the Netherlands, notified the FAA that an unsafe 
condition may exist on all Fokker F28 Mark 1000, 2000, 3000, and 4000 
series airplanes. The RLD advises that corrosion has been found inside 
the rear cargo door during the replacement of the door hinge on several 
of the affected airplanes. In one instance, corrosion was so severe 
that a number of parts required replacement. The location of the rear 
cargo door is such that toilet fluids may enter the door, and the 
insulation blankets may absorb these fluids, which could cause a 
continuous corrosive environment inside the door. This condition, if 
not detected and corrected in a timely manner, could result in 
structural failure of the cargo door and loss of the door during 
flight, which could result in rapid decompression, aerodynamic 
instability, and/or damage to other fuselage structures.

Explanation of Relevant Service Information

    Fokker has issued Service Bulletin F28-52-111, dated March 12, 
1994, which describes procedures for the following:

--A one-time visual inspection of the rear cargo door and auxiliary 
structure for corrosion;
--Removal and repair of any corrosion;
--Drilling drain holes and applying a corrosion preventive and sealing 
compound inside the rear cargo door; and
--Modification of the rear cargo door to provide inspection holes for 
borescope inspections.

    The RLD classified this service bulletin as mandatory and issued 
Dutch airworthiness directive BLA No. 1995-126 (A), dated November 30, 
1995, in order to assure the continued airworthiness of these airplanes 
in the Netherlands.

FAA's Conclusions

    These airplane models are manufactured in the Netherlands and are 
type certificated for operation in the United States under the 
provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 
21.29) 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.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would require a one-time visual 
inspection of the rear cargo door and luggage auxiliary structure for 
corrosion, repetitive borescope inspections of the rear cargo door, and 
removal and repair of any corrosion found during the inspections.

[[Page 29309]]

This proposed AD would also require the drilling of drain holes and 
application of a corrosion preventive and sealing compound inside the 
rear cargo door, and modification of the rear cargo door to aid in the 
future routine borescope inspections. The actions would be required to 
be accomplished in accordance with the service bulletin described 
previously, except for the repetitive borescope inspections and follow-
on actions, which would be required to be accomplished in accordance 
with the F28 Maintenance Manual.

Cost Impact

    The FAA estimates that 37 airplanes of U.S. registry would be 
affected by this proposed AD.
    It would take approximately 13 work hours per airplane to 
accomplish the proposed initial inspection, at an average labor rate of 
$60 per work hour. The FAA has no way of determining how many 
repetitive inspections the owners/operators would incur over the life 
of the affected airplanes. Based on these figures, the cost impact of 
the initial inspection proposed by this AD on U.S. operators is 
estimated to be $28,860, or $780 per airplane.
    It would take approximately 27 work hours per airplane to 
accomplish the proposed modification, at an average labor rate of $60 
per work hour. Required parts would be supplied by the manufacturer at 
no cost to the operators. Based on these figures, the cost impact of 
the modification proposed by this AD on U.S. operators is estimated to 
be $59,940, or $1,620 per airplane.
    The cost impact figures discussed above are 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.

Regulatory Impact

    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 
part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new 
airworthiness directive:

Fokker: Docket 96-NM-174-AD.

    Applicability: All F28 Mark 1000, 2000, 3000, and 4000 series 
airplanes, certificated in any category.

    Note 1. This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (c) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent corrosion in the rear cargo door, which could result 
in structural failure of the cargo door and loss of the door during 
flight, and consequent rapid decompression, aerodynamic instability, 
and/or damage to other fuselage structures, accomplish the 
following:
    (a) Within 2 years after the effective date of this AD, 
accomplish the requirements of paragraphs (a)(1), (a)(2), and (a)(3) 
of this AD, in accordance with Fokker Service Bulletin F28-52-111, 
dated March 12, 1994.
    (1) Perform a one-time visual inspection of the rear cargo door 
and luggage auxiliary structure for corrosion. If any corrosion is 
found, prior to further flight, remove and repair it.
    (2) Drill drain holes and apply a corrosion preventive and 
sealing compound inside the rear cargo door.
    (3) Modify the rear cargo door to provide inspection holes for 
borescope inspections.
    (b) Within 6,000 hours time-in-service (TIS) or 3 years after 
accomplishing the visual inspection required by paragraph (a)(1) of 
this AD, whichever occurs first; and thereafter at intervals not to 
exceed 6,000 hours TIS or 3 years, whichever occurs first: Perform a 
borescope inspection of the rear cargo door for corrosion in 
accordance with Chapter 52-30-2 of the F28 Maintenance Manual. If 
any corrosion is detected, prior to further flight, remove and 
repair it in accordance with the maintenance manual.
    (c) 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.

    (d) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 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 May 23, 1997.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 97-14183 Filed 5-29-97; 8:45 am]
BILLING CODE 4910-13-P