[Federal Register Volume 64, Number 205 (Monday, October 25, 1999)]
[Proposed Rules]
[Pages 57409-57413]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-27792]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-NM-94-AD]
RIN 2120-AA64
Airworthiness Directives; Aerospatiale Model ATR42-200, ATR42-
300, and ATR42-320 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the supersedure of an existing
airworthiness directive (AD), applicable to certain Aerospatiale Model
ATR42-300 and ATR42-320 series airplanes, that currently requires
inspections to determine the proper installation of rivets in certain
key holes and to detect cracks in the area of the key holes where
rivets are missing; and correction of discrepancies. This action would
increase the compliance time for the existing requirements and expand
the
[[Page 57410]]
applicability of the existing AD to include additional airplanes. This
action also would require various inspections of the subject area for
discrepancies, and corrective actions, if necessary; and replacement of
certain cargo door hinges with new hinges. For certain airplanes, this
action would also require replacement of friction plates, stop
fittings, and bolts with new parts. This proposal is prompted by
issuance of mandatory continuing airworthiness information by a foreign
civil airworthiness authority. The actions specified by the proposed AD
are intended to prevent fatigue cracks of the cargo door skin, certain
frames, and entry door stop fittings and friction plates, which could
result in reduced structural integrity of the airplane.
DATES: Comments must be received by November 24, 1999.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 98-NM-94-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 Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex
03, France. This information may be examined at the FAA, Transport
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.
FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager,
International Branch, ANM-116, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425)
227-2110; 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 98-NM-94-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-114, Attention: Rules
Docket No. 98-NM-94-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
On September 10, 1993, the FAA issued AD 93-18-04, amendment 39-
8689 (58 FR 53853, October 19, 1993), applicable to certain
Aerospatiale Model ATR42-300 and ATR42-320 series airplanes, to require
an inspection to determine the proper installation of rivets in the key
holes of certain fuselage frames; an inspection to detect cracks in
area of the key holes where rivets are missing; and correction of
discrepancies. That action was prompted by the discovery of cracks
around key holes on fuselage frames 25 and 27 where rivets were
missing. The requirements of that AD are intended to prevent the loss
of strength of the fuselage frames.
Actions Since Issuance of Previous Rule
Since the issuance of that AD, the Direction Generale de l'Aviation
Civile (DGAC), which is the airworthiness authority for France, advises
that Aerospatiale has continued fatigue testing of Aerospatiale Model
ATR42-300 and ATR42-320 series airplanes. The DGAC has determined that,
in addition to fuselage frames 25 and 27 there are other areas that
require inspection and modification, if applicable, to ensure that
fatigue cracks do not progress undetected and reduce the structural
integrity of the airplane. These additional areas of concern include
cargo door fasteners and hinges; certain standard fuselage frames;
forward entry door stops, door stop bolts, friction and plates; and
upper corners. Additionally, the DGAC has determined that the subject
area on certain Model ATR42-200 series airplanes, which were not
affected by AD 93-18-04, is identical to that on the affected Model
ATR42-300 and ATR42-320 series airplanes. Therefore, all of these
airplanes may be subject to the unsafe condition and should have
fuselage frames 25 and 27 inspected.
Explanation of Relevant Service Information
Aerospatiale has issued Service Bulletin ATR42-53-0070, Revision 2,
dated March 22, 1993, which describes procedures for a general visual
inspection to determine the proper installation of rivets in the key
holes of certain fuselage frames; and corrective action, if necessary.
The corrective actions involve performing an eddy current inspection to
detect cracks in the area of the key holes where rivets are missing,
and installing rivets in uncracked holes.
Aerospatiale has issued Service Bulletin ATR42-52-0058, Revision 1,
dated March 1, 1995, which describes procedures for replacement of the
hinges on the cargo compartment door and fuselage with new improved
hinges. The replacement procedures include inspections for fastener
type and tolerances, hole diameters, or cracking, and repair; as
applicable.
Aerospatiale has issued Service Bulletin ATR42-53-0076, Revision 2,
dated October 15, 1996, which describes procedures for a general visual
inspection of certain fuselage frames for proper installation of
rivets, and corrective action, if necessary. The corrective actions
involve a general visual inspection for cracks in the tooling or key
holes, and installation of rivets in uncracked holes.
Aerospatiale also has issued Service Bulletin ATR42-52-0052,
Revision 1, dated March 2, 1993, which describes procedures for an eddy
current inspection of forward entry door stop holes to detect cracking;
a detailed visual inspection of forward entry door friction plates to
detect wear; and corrective action, if necessary. The corrective action
involves replacement of door stop fittings and friction plates with new
parts.
Aerospatiale also has issued Service Bulletin ATR42-52-0059, dated
February 16, 1995, which describes procedures for replacement of
forward entry door friction plates, upper corner stop fittings, and
bolts with parts of an improved design.
Accomplishment of the actions specified in the service bulletins is
intended to adequately address the identified unsafe condition. The
DGAC classified these service bulletins as
[[Page 57411]]
mandatory and issued French airworthiness directive 92-044-046(B)R2,
dated November 5, 1997, in order to assure the continued airworthiness
of these airplanes in France.
FAA's Conclusions
These airplane models are manufactured in France 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 DGAC has kept the FAA informed
of the situation described above. The FAA has examined the findings of
the DGAC, 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 supersede AD 93-18-04 to
require accomplishment of the actions specified in the service
bulletins described previously. The actions would be required to be
accomplished in accordance with the service bulletins described
previously, except as discussed below.
Differences Between Proposed Rule and Service Bulletin
Operators should note that, although certain service bulletins
described previously specify that the manufacturer may be contacted for
disposition of certain repair conditions, this proposal would require
the repair of those conditions to be accomplished in accordance with a
method approved by the FAA or the DGAC (or its delegated agent). In
light of the type of repair that would be required to address the
identified unsafe condition, and in consonance with existing bilateral
airworthiness agreements, the FAA has determined that, for this
proposed AD, a repair approved by either the FAA or the DGAC would be
acceptable for compliance with this proposed AD.
Cost Impact
There are approximately 106 airplanes of U.S. registry that would
be affected by this proposed AD.
The general visual inspection of fuselage frames 25 and 27 that is
proposed in this AD action would take approximately 3 work hours per
airplane to accomplish, at an average labor rate of $60 per work hour.
Based on these figures, the cost impact of this inspection proposed by
this AD on U.S. operators is estimated to be $180 per airplane.
The cargo door hinge and skin replacement that is proposed in this
AD action would take approximately 250 work hours per airplane to
accomplish, at an average labor rate of $60 per work hour. Required
parts would cost approximately $9,880 per airplane. Based on these
figures, the cost impact of the door structure replacement proposed by
this AD on U.S. operators is estimated to be $24,880 per airplane.
The general visual inspection of the key and tooling holes that is
proposed in this AD action would take approximately 100 work hours per
airplane to accomplish, at an average labor rate of $60 per work hour.
Based on this figure, the cost impact of this inspection proposed by
this AD on U.S. operators is estimated to be $6,000 per airplane.
The eddy current and detailed visual inspections of the forward
entry door stop fitting and friction plate that are proposed in this AD
action would take approximately 2 work hours per airplane to
accomplish, at an average labor rate of $60 per work hour. Based on
this figure, the cost impact of these inspections proposed by this AD
on U.S. operators is estimated to be $120 per airplane.
The replacement of the forward entry door stop fitting, friction
plate, and upper door corner that is proposed in this AD action would
take approximately 50 work hours per airplane to accomplish. The
manufacturer has committed previously to its customers that it will
bear the cost of replacement parts. As a result, the cost of those
parts is not attributable to this proposed AD. Based on this figure,
the cost impact of the replacement proposed by this AD on U.S.
operators is estimated to be $3,000 per airplane.
The cost impact figures discussed above are based on assumptions
that no operator has yet accomplished any of the current or 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 removing amendment 39-8689 (58 FR
53853, October 19, 1993), and by adding a new airworthiness directive
(AD), to read as follows:
Aerospatiale: Docket 98-NM-94-AD. Supersedes AD 93-18-04, Amendment
39-8689.
Applicability: All Model ATR42-200, ATR42-300, and ATR42-320
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
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 (h) 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
[[Page 57412]]
been eliminated, the request should include specific proposed
actions to address it.
Compliance: Required as indicated, unless accomplished
previously.
To prevent fatigue cracks of the cargo door skin, certain
frames, entry door stop fittings, or friction plates, which could
result in reduced structural integrity of the airplane, accomplish
the following:
Frame 25 and 27 Inspection
(a) For airplanes having serial numbers 005 through 016
inclusive, 018 through 030 inclusive, 032 through 036 inclusive,
038, 040, 042, 043, 048 through 062 inclusive, 064 through 090
inclusive, 092 through 094 inclusive, and 096 through 228 inclusive:
Prior to the accumulation of 36,000 total flight cycles, or within
180 days after the effective date of this AD, whichever occurs
later, conduct a general visual inspection of fuselage frames 25 and
27 to verify the proper installation of a rivet in each of the key
holes, in accordance with Aerospatiale Service Bulletin ATR42-53-
0070, Revision 2, dated March 22, 1993.
Note 2: For the purposes of this AD, a general visual inspection
is defined as ``A visual examination of an interior or exterior
area, installation, or assembly to detect obvious damage, failure,
or irregularity. This level of inspection is made under normally
available lighting conditions such as daylight, hangar lighting,
flashlight, or drop-light, and may require removal or opening of
access panels or doors. Stands, ladders, or platforms may be
required to gain proximity to the area being check.''
Note 3: Inspection of fuselage frames 25 and 27 accomplished
prior to the effective date of this AD in accordance with
Aerospatiale Service Bulletin ATR42-53-0070, dated June 10, 1991, or
Revision 1, dated June 12, 1992, is considered acceptable for
compliance with the requirements of paragraph (a) of this AD.
(1) If a rivet is installed in each of the key holes, no further
action is required by this paragraph.
(2) If a rivet is not installed in each of the key holes, prior
to further flight, perform an eddy current inspection of each open
key hole to detect cracks, in accordance with the service bulletin.
(i) If no crack is found during the eddy current inspection,
prior to further flight, install a rivet in the open key hole in
accordance with the service bulletin. After such installation, no
further action is required by this paragraph for that key hole.
(ii) If any crack is found during the eddy current inspection,
prior to further flight, repair the crack in accordance with a
method approved by the Manager, International Branch, ANM-116, FAA,
Transport Airplane Directorate, or the Direction Generale de
l'Aviation Civile (DGAC) (or its delegated agent). For a repair
method to be approved by the Manager, International Branch, ANM-116,
as required by this paragraph, the Manager's approval letter must
specifically reference this AD.
Inspection and Modification of Cargo Door Structure
(b) For airplanes equipped with a cargo compartment door on
which Aerospatiale Modification 3191 has not been accomplished:
Prior to the accumulation of 27,000 total flight cycles, or within
180 days after the effective date of this AD, whichever occurs
later, except as provided by paragraph (c) of this AD, replace the
hinges on the cargo compartment door and fuselage (including
inspections for fastener type and tolerances, hole diameters, or
cracking, and repair; as applicable) with new improved hinges, in
accordance with paragraph 2. of the Accomplishment Instructions of
Aerospatiale Service Bulletin ATR42-52-0058, Revision 1, dated March
1, 1995.
(c) Where the instructions in Aerospatiale Service Bulletin
ATR42-52-0058, Revision 1, dated March 1, 1995, specify that ATR is
to be contacted for a repair, prior to further flight, repair in
accordance with a method approved by the Manager, International
Branch, ANM-116, or the DGAC (or its delegated agent).
Frame Inspection
(d) For airplanes having serial numbers 003 through 208
inclusive: Prior to the accumulation of 36,000 total flight cycles,
or within 180 days after the effective date of this AD, whichever
occurs later, conduct a general visual inspection of the identified
fuselage frames for proper installation of a rivet in each of the
tooling and key holes, in accordance with Aerospatiale Service
Bulletin ATR42-53-0076, Revision 2, dated October 15, 1996.
(1) If a rivet is installed in each of the tooling or key holes,
no further action is required by this paragraph.
(2) If a rivet is not installed in each of the tooling and key
holes, prior to further flight, perform a detailed visual inspection
of each open tooling or key hole to detect cracks, in accordance
with the service bulletin.
Note 4: For the purposes of this AD, a detailed visual
inspection is defined as: ``An intensive visual examination of a
specific structural area, system, installation, or assembly to
detect damage, failure, or irregularity. Available lighting is
normally supplemented with a direct source of good lighting at
intensity deemed appropriate by the inspector. Inspection aids such
as mirror, magnifying lenses, etc. may be used. Surface cleaning and
elaborate access procedures may be required.''
(i) If no crack is found during the detailed visual inspection
required by paragraph (d)(2) of this AD, prior to further flight,
install a rivet in the open hole in accordance with the service
bulletin.
(ii) If any crack is found during the visual inspection required
by paragraph (d)(2) of this AD, prior to further flight, repair the
crack in accordance with a method approved by the Manager,
International Branch, ANM-116, or the DGAC (or its delegated agent).
Inspection and/or Replacement of Entry Door Structure
(e) For Model ATR42-300 series airplanes having serial numbers
listed in Aerospatiale Service Bulletin ATR42-52-0052, Revision 1,
dated March 2, 1993: Except as provided by paragraph (f) of this AD,
prior to the accumulation of 10,000 total flight cycles, or within
90 days after the effective date of this AD, whichever occurs later,
accomplish the requirements of paragraphs (e)(1) and (e)(2) of this
AD.
(1) Perform an eddy current inspection of the forward entry door
stop holes to detect cracking, in accordance with the service
bulletin. If any cracking is detected, prior to further flight,
replace any cracked forward entry door stop fitting with a new
fitting, in accordance with the service bulletin.
(2) Perform a detailed visual inspection of the forward entry
door friction plates for wear, in accordance with the service
bulletin. If wear is found on any friction plate, and the wear has a
depth equal to or greater than 0.8mm (0.0315 in.), prior to further
flight, replace the friction plate with a new or serviceable part in
accordance with the service bulletin.
(f) For Model ATR42-300 series airplanes listed in Aerospatiale
Service Bulletin ATR42-52-0052, Revision 1, dated March 2, 1993,
accomplishment of the requirements of paragraph (g) of this AD at
the time specified in paragraph (e) of this AD constitutes
terminating action for the requirements of paragraph (e) of this AD.
(g) For Model ATR42-300 series airplanes listed in Aerospatiale
Service Bulletin ATR42-52-0059, dated February 16, 1995: Prior to
the accumulation of 18,000 total flight cycles, or within 180 days
after the effective date of this AD, whichever occurs later,
accomplish the requirements of paragraphs (g)(1), (g)(2), and (g)(3)
of this AD in accordance with the service bulletin.
(1) Replace the forward entry door friction plates with improved
friction plates.
(2) Replace the upper corners of the forward entry door surround
structure with improved door surround corners.
(3) Replace the forward entry door stop fittings and bolts with
improved fittings and bolts.
Alternative Methods of Compliance
(h) 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, International Branch, ANM-116.
Operators shall submit their requests through an appropriate FAA
Principal Maintenance Inspector, who may add comments and then send
it to the Manager, International Branch, ANM-116.
Note 5: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the International Branch, ANM-116.
Special Flight Permits
(i) 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.
Note 6: The subject of this AD is addressed in French
airworthiness directive 92-044-046(B)R2, dated November 5, 1997.
[[Page 57413]]
Issued in Renton, Washington, on October 19, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 99-27792 Filed 10-22-99; 8:45 am]
BILLING CODE 4910-13-P
