[Federal Register Volume 59, Number 22 (Wednesday, February 2, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-2335]


[[Page Unknown]]

[Federal Register: February 2, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 93-NM-193-AD]

 

Airworthiness Directives; Fokker Model F28 Mark 0100 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 F28 Mark 0100 
series airplanes. This proposal would require inspections to detect 
corrosion in the wheel axles of the main landing gear (MLG) sliding 
members; and, if any corrosion is found, rework of corroded areas and 
an inspection to detect cracks in the wheel axles; and, if any crack is 
found, replacement of the cracked sliding member. This proposal is 
prompted by a report that a MLG wheel axle failed during push back of 
an in-service airplane from the terminal. The actions specified by the 
proposed AD are intended to prevent failure of the MLG wheel axle due 
to the problems associated with corrosion and cracking.

DATES: Comments must be received by March 29, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 93-NM-193-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: Tim Dulin, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-2141; 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-193-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-193-AD, 1601 Lind Avenue SW., Renton, Washington 
98055-4056.

Discussion

    The Rijksluchtvaartdienst (RLD), which is the airworthiness 
authority for the Netherlands, recently notified the FAA that an unsafe 
condition may exist on certain Fokker Model F28 Mark 0100 series 
airplanes. The RLD advises that an operator of Model F28 Mark 0100 
series airplanes reported the failure of a main landing gear (MLG) 
wheel axle during push back of an in-service airplane from the 
terminal. Subsequent non-destructive testing (NDT) inspection of the 
operator's fleet of Model F28 Mark 0100 series airplanes revealed that 
corrosion was present on most MLG wheel axles examined. Although no 
cracks were found during this inspection, preliminary findings indicate 
that the crack which led to the failed axle had initiated from a 
corrosion pit located on the radius of the brake abutment flange on the 
axle. Corrosion and cracking in a MLG wheel axle, if not detected and 
corrected in a timely manner, could result in failure of the MLG wheel 
axle.
    Fokker has issued Service Bulletin SBF100-32-079, Revision 1, dated 
October 4, 1993, that describes procedures for removal of the MLG 
wheels and brakes, inspections of the wheel axles, and reinstallation 
of MLG wheels and brakes. The Fokker service bulletin references Dowty 
Aerospace Service Bulletin F100-32-63, Revision 2, dated September 23, 
1993, as the appropriate source of service information for the wheel 
axle inspection. The Dowty Aerospace service bulletin describes 
procedures for a visual inspection to detect corrosion in the wheel 
axles of the MLG sliding members; and, if any corrosion is found, 
rework of corroded areas and an NDT inspection to detect cracks in the 
wheel axles; and, if any crack is found, replacement of the cracked 
sliding member.
    Fokker Service Bulletin SBF100-32-080, dated October 4, 1993, and 
Dowty Aerospace Service Bulletin F100-32-64, dated September 23, 1993, 
describe procedures for accomplishing the corresponding repetitive 
actions described in the service bulletins discussed previously. The 
RLD classified these service bulletins as mandatory and issued 
Netherlands Airworthiness Directive BLA 93-108/2 (A), dated November 1, 
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 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 repetitive visual 
inspections to detect corrosion in the wheel axles of the MLG sliding 
members; and, if any corrosion is found, rework of corroded areas and 
an NDT inspection to detect cracks in the wheel axles; and, if any 
crack is found, replacement of the cracked sliding member. The actions 
would be required to be accomplished in accordance with the service 
bulletins described previously.
    The FAA estimates that 100 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 14 work 
hours per airplane to accomplish the proposed actions, and that the 
average labor rate is $55 per work hour. Based on these figures, the 
recurring cost impact of the proposed AD on U.S. operators (for four 
inspections per year) is estimated to be $308,000 per year, or $3,080 
per airplane per year. This total cost figure assumes that no operator 
has yet accomplished the proposed requirements of this AD action.
    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-193-AD.

    Applicability: Model F28 Mark 0100 series airplanes equipped 
with Dowty Aerospace main landing gear (MLG) part number 201072011, 
201072012, 201072013, 201072014, 201072015, or 201072016; 
certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent failure of the MLG wheel axle, accomplish the 
following:
    (a) Within 30 days after the effective date of this AD, remove 
the MLG wheels and brakes and perform a visual inspection to detect 
corrosion in the wheel axles of the MLG sliding members in 
accordance with Fokker Service Bulletin F100-32-079, Revision 1, 
dated October 4, 1993, and paragraph 2.A. of the Accomplishment 
Instructions of Dowty Aerospace Service Bulletin F100-32-63, 
Revision 2, dated September 23, 1993.
    (b) Repeat the inspection required by paragraph (a) of this AD 
thereafter at intervals not to exceed 3 months in accordance with 
Fokker Service Bulletin SBF100-32-080, dated October 4, 1993, and 
Dowty Aerospace Service Bulletin F100-32-64, dated September 23, 
1993.
    (c) If any corrosion is found during any inspection required by 
paragraph (a) or (b) of this AD, prior to further flight, rework the 
affected area and perform a non-destructive testing (NDT) inspection 
to detect cracks in the MLG wheel axles, in accordance with Appendix 
A of Dowty Aerospace Service Bulletin F100-32-63, Revision 2, dated 
September 23, 1993 (if corrosion is found during the initial 
inspection required by this AD); or Dowty Aerospace Service Bulletin 
F100-32-64, dated September 23, 1993 (if corrosion is found during a 
repetitive inspection required by this AD); as applicable. After 
rework, continue to perform repetitive inspections of the affected 
area in accordance with paragraph (b) of this AD.
    (d) If any crack is found during the inspections required by 
paragraph (c) of this AD, prior to further flight, replace the 
affected sliding member with a serviceable sliding member in 
accordance with Dowty Aerospace Service Bulletin F100-32-63, 
Revision 2, dated September 23, 1993 (if any crack is found during 
the initial inspection required by this AD); or Dowty Aerospace 
Service Bulletin F100-32-64, dated September 23, 1993 (if any crack 
is found during a repetitive inspection required by this AD); as 
applicable. After replacement of the affected sliding member, 
continue to perform the repetitive inspections in accordance with 
paragraph (b) of this AD.
    (e) As of the effective date of this AD, no person shall install 
a Dowty Aerospace MLG, part number 201072011, 201072012, 201072013, 
201072014, 201072015, or 201072016, on any airplane unless the 
requirements of this AD have been accomplished on that MLG. 
Following its installation, the repetitive inspections required by 
paragraph (b) of this AD shall be accomplished on that MLG.
    (f) 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: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.

    (g) Special flight permits may be issued in accordance with 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 January 27, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-2335 Filed 2-1-94; 8:45 am]
BILLING CODE 4910-13-U