[Federal Register Volume 62, Number 68 (Wednesday, April 9, 1997)]
[Proposed Rules]
[Pages 17129-17131]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-9015]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 96-NM-113-AD]
RIN 2120-AA64
Airworthiness Directives; Dornier Model 328-100 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 Dornier Model 328-100
series airplanes. This proposal would require repetitive inspections to
detect cracking of the support beam of the main landing gear (MLG)
fairing, and permanent repair of any cracking found. Accomplishment of
the permanent repair terminates the repetitive inspections. This
proposal is prompted by reports of cracking of the support beam of the
MLG fairing. The actions specified by the proposed AD are intended to
prevent such cracking, which could result in reduced structural
integrity of the lower part of the MLG fairing, and subsequent
separation of part of the fairing from the airplane.
DATES: Comments must be received by May 19, 1997.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 96-NM-113-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 Dornier Luftfahrt GmbH, P.O. Box 1103, D-82230 Wessling,
Germany. This information may be examined at the FAA, Transport
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.
FOR FURTHER INFORMATION CONTACT: Connie Beane, Aerospace Engineer,
[[Page 17130]]
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206)
227-2796; fax (206) 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-113-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-113-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority
for Germany, recently notified the FAA that an unsafe condition may
exist on certain Dornier Model 328-100 series airplanes. The LBA
advises that it received reports of cracking of the support beam of the
main landing gear (MLG) fairing on these airplanes. The cracking was
found during maintenance of the airplanes. This cracking occurs at
design-critical locations; the design is not adequate due to severe
bending of materials at these locations. Cracking of the support beam
of the MLG fairing, if not corrected, could result in reduced
structural integrity of the lower part of the MLG fairing, and
subsequent separation of part of the fairing from the airplane.
Explanation of Relevant Service Information
Dornier has issued Alert Service Bulletin ASB-328-53-010, dated
October 13, 1995, which describes procedures for repetitive visual
inspections to detect cracking of the lower attachment flanges in the
area of the bend radii of the forward and aft support beams of the MLG.
The alert service bulletin also describes procedures for a temporary
repair (for cracking within specified limits) and a permanent repair
(for cracking outside specified limits). The temporary repair entails
stop drilling the crack, and performing subsequent visual inspections
until the permanent repair is accomplished, or until results of the
visual inspections reveal that the length of the crack has increased to
more than 50 mm. Among other things, the permanent repair involves wet
installing and sealing the angle, protecting reworked surfaces, and
reworking the existing flange. Accomplishment of the permanent repair
eliminates the need for the repetitive inspections. The LBA classified
this alert service bulletin as mandatory and issued German
airworthiness directive 95-413, dated November 2, 1995, in order to
assure the continued airworthiness of these airplanes in Germany.
FAA's Conclusions
This airplane model is manufactured in Germany and is type
certificated for operation in the United States under the provisions of
Sec. 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the
applicable bilateral airworthiness agreement. Pursuant to this
bilateral airworthiness agreement, the LBA has kept the FAA informed of
the situation described above. The FAA has examined the findings of the
LBA, 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, the
proposed AD would require repetitive visual inspections to detect
cracking of the lower attachment flanges in the area of the bend radii
of the forward and aft support beams of the MLG, and permanent repair
of any cracking found. The actions would be required to be accomplished
in accordance with the alert service bulletin described previously.
Differences Between Alert Service Bulletin and This Proposed AD
Operators should note that, while the alert service bulletin
recommends accomplishment of a temporary repair for cracking within
specified limits, and a permanent repair for cracking outside those
limits, this proposed AD would require that the permanent repair be
accomplished for airplanes on which cracking of any length is found.
The FAA has determined that, due to the safety implications and
consequences associated with such cracking, the permanent repair must
be accomplished prior to further flight on all beams that are found to
be cracked.
Cost Impact
The FAA estimates that 27 Dornier Model 328-100 series airplanes of
U.S. registry would be affected by this proposed AD, that it would take
approximately 1 work hour per airplane to accomplish the proposed
actions, and that the average labor rate is $60 per work hour. Based on
these figures, the cost impact of the proposed AD on U.S. operators is
estimated to be $1,620, or $60 per airplane.
The 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.
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.
[[Page 17131]]
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:
Dornier: Docket 96-NM-113-AD.
Applicability: Model 328-100 series airplanes, excluding serial
numbers 3006, 3007, and 3010; 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 (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 reduced structural integrity of the lower part of the
MLG fairing, and subsequent separation of part of the fairing from
the airplane, accomplish the following:
(a) Within 300 hours time-in-service after the effective date of
this AD, perform a visual inspection to detect cracking of the lower
attachment flanges in the area of the bend radii of the forward and
aft support beams of the main landing gear (MLG), in accordance with
Dornier Alert Service Bulletin ASB-328-53-010, dated October 13,
1995.
(1) If no cracking is found, repeat the inspection thereafter at
intervals not to exceed 300 hours time-in-service.
(2) If any cracking is found, prior to further flight,
accomplish the permanent repair in accordance with the alert service
bulletin.
(b) Accomplishment of the permanent repair in accordance with
Dornier Alert Service Bulletin ASB-328-53-010, dated October 13,
1995, constitutes terminating action for the repetitive inspections
required by this AD.
(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 April 2, 1997.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 97-9015 Filed 4-8-97; 8:45 am]
BILLING CODE 4910-13-U
