[Federal Register Volume 60, Number 113 (Tuesday, June 13, 1995)]
[Rules and Regulations]
[Pages 31065-31067]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-13891]



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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 95-NM-60-AD; Amendment 39-9258; AD 95-12-08]


Airworthiness Directives; Aerospatiale Model ATR72-101, -102, and 
-202 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Aerospatiale Model ATR72 series airplanes. This 
action requires repetitive inspections to detect displacement of the 
rear hinge bush, and to detect cracking or rupture of the rear hinge 
pin on the main landing gear (MLG) leg; and the correction of any 
discrepancies. This amendment is prompted by a report of the failure of 
this hinge pin on an in-service airplane. The actions specified in this 
AD are intended to prevent failure of the hinge pin, which can lead to 
failure of the MLG leg or MLG attachment assembly.

DATES: Effective June 28, 1995.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of June 28, 1995.
    Comments for inclusion in the Rules Docket must be received on or 
before August 14, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 95-NM-65-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056.
    The service information referenced in this AD 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; or at the Office 
of the Federal Register, 800 North Capitol Street NW., suite 700, 
Washington, DC.

FOR FURTHER INFORMATION CONTACT: Sam Grober, Aerospace Engineer, 
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
227-1187; fax (206) 227-1320.

SUPPLEMENTARY INFORMATION: The Direction Generale de l'Aviation Civile 
(DGAC), which is the airworthiness authority for France, recently 
notified the FAA that an unsafe condition may exist on certain 
Aerospatiale Model ATR72-101, -102, and -202 series airplanes. The DGAC 
advises that there has been a report of the failure (rupture) of the 
rear hinge pin on the main landing gear (MLG) leg of one in-service 
airplane. The cause of the failure is associated with a quality problem 
during the manufacture of these hinge pins, which apparently causes the 
pin to be susceptible to cracking. The suspect pins have part number 
(P/N) D 61000. Failure of the hinge pin could lead to the failure of 
the MLG leg or the MLG attachment assembly.
    Avions de Transport Regional (ATR) has issued Service Bulletin 
ATR72-32-1028, dated September 1, 1994, which describes procedures for 
performing the following actions:
    1. repetitive visual inspections of the MLG rear hinge pin bush to 
ensure that the bush has not moved and that the sealant at the level of 
the bush does not show any cracks, and correction of discrepancies; and
    2. repetitive boroscope inspections to detect cracks of the MLG 
leg-to-aircraft rear hinge pin, and replacement of the pin, if 
necessary (This ATR service bulletin references Messier-Eram Service 
Bulletin 631-32-110, dated August 31, 1994, for additional inspection 
instructions.)
    ATR has also issued Service Bulletin ATR72-32-1029, dated November 
4, 1994, which describes procedures for performing an ultrasonic 
inspection of the MLG aft hinge pins to ensure that the pin is free of 
material defects, and replacement of the pin with new pin, if 
necessary. (This service bulletin references Messier-Eram Service 
Bulletin 631-32-111, dated October 14, 1994, for additional inspection 
instructions.)
    The DGAC classified these service bulletins as mandatory and issued 
French Airworthiness Directive (CN) 94-197-023(B), dated August 31, 
1994, in order to assure the continued airworthiness of these airplanes 
in France.
    This airplane model is manufactured in France and is type 
certificated for operation in the United States under the provisions of 
section 21.29 of the Federal Aviation Regulations (14 CFR 21.19) and 
the applicable bilateral airworthiness agreement. Pursuant to 
[[Page 31066]] 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.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design, this AD is 
being issued to prevent failure of the rear hinge pin on the MLG leg, 
which could lead to failure of the MLG leg or the MLG attachment 
assembly. This AD requires, initially, repetitive visual inspections 
off the MLG rear hinge pin bush to ensure that the bush has not moved 
and that the sealant at the level of the bush does not show any cracks, 
and correction of discrepancies. It also requires repetitive boroscope 
inspections to detect cracks of the MLG leg-to-aircraft rear hinge pin, 
and replacement of the pin, if necessary. As terminating action for 
those inspections, this AD requires an ultrasonic inspection of the MLG 
aft hinge pins to ensure that the pin is free of material defects, and 
replacement of the pin with new pin, if necessary. These actions are 
required to be accomplished in accordance with the service bulletins 
described previously.
    As a result of recent communications with the Air Transport 
Association (ATA) of America, the FAA has learned that, in general, 
some operators may misunderstand the legal effect of AD's on airplanes 
that are identified in the applicability provision of the AD, but that 
have been altered or repaired in the area addressed by the AD. The FAA 
points out that all airplanes identified in the applicability provision 
of an AD are legally subject to the AD. If an airplane has been altered 
or repaired in the affected area in such a way as to affect compliance 
with the AD, the owner or operator is required to obtain FAA approval 
for an alternative method of compliance with the AD, in accordance with 
the paragraph of each AD that provides for such approvals. A note has 
been included in this AD to clarify this long-standing requirement.
    There currently are no affected Model ATR72-101, -102, or -202 
series airplanes on the U.S. Register. All airplanes included in the 
applicability of this rule currently are operated by non-U.S. operators 
under foreign registry; therefore, they are not directly affected by 
this AD action. However, the FAA considers that this rule is necessary 
to ensure that the unsafe condition is addressed in the event that any 
of these subject airplanes are imported and placed on the U.S. Register 
in the future.
    Should an affected airplane be imported and placed on the U.S. 
Register in the future, the following costs would apply:
    Accomplishment of a required repetitive visual inspections would 
require approximately .5 work hour per bush, at an average labor charge 
of $60 per work hour. Based on these figures, the total cost impact of 
this requirement would be $30 per bush per inspection.
    Accomplishment of a required repetitive boroscope inspections would 
require approximately 3 work hours per pin, at an average labor charge 
of $60 per work hour. Based on these figures, the total cost impact of 
this requirement would be $180 per pin per inspection.
    Accomplishment of a required one-time ultrasonic inspection would 
require approximately 11 work hours per pin, at an average labor charge 
of $60 per work hour. Based on these figures, the total cost impact of 
this requirement would be $180 per pin.
    Since this AD action does not affect any airplane that is currently 
on the U.S. register, it has no adverse economic impact and imposes no 
additional burden on any person. Therefore, notice and public 
procedures hereon are unnecessary and the amendment may be made 
effective in less than 30 days after publication in the Federal 
Register.

Comments Invited

    Although this action is in the form of a final rule and was not 
preceded by notice and opportunity for public comment, comments are 
invited on this rule. Interested persons are invited to comment on this 
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 under the caption 
ADDRESSES. All communications received on or before the closing date 
for comments will be considered, and this rule may be amended in light 
of the comments received. Factual information that supports the 
commenter's ideas and suggestions is extremely helpful in evaluating 
the effectiveness of the AD action and determining whether additional 
rulemaking action would be needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 95-NM-60-AD.'' The postcard will be date stamped and 
returned to the commenter.
    The regulations adopted herein will 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 final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this action (1) Is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from the Rules Docket at the location provided under the caption 
ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends 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. 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:

95-12-08  Aerospatiale: Amendment 39-9258 Docket 95-NM-60-AD.

    [[Page 31067]] Applicability: Model AT472-101, -102, and -202 
series airplanes, as listed in ATR Service Bulletin ATR72-32-1028, 
dated September 1, 1994; equipped with main landing gear hinge pins 
having part number (P/N) D 61000 with serial numbers MN 76 through 
MN 86 inclusive; 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 use the authority 
provided in paragraph (d) to request approval from the FAA. This 
approval may address either no action, if the current configuration 
eliminates the unsafe condition; or different actions necessary to 
address the unsafe condition described in this AD. Such a request 
should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any airplane from the applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent failure of the rear hinge pin on the main landing 
gear (MLG) leg, which can lead to failure of the MLG leg or 
attachment assembly, accomplish the following:
    (a) Within 90 days after the effective date of this AD, perform 
a detailed visual inspection of the MLG rear hinge pin bush to 
determine if the bush has moved or if the sealant at the level of 
the bush shows any cracks, in accordance with ATR Service Bulletin 
ATR72-32-1028, dated September 1, 1994.

    Note 2: ATR Service Bulletin ATR72-32-1028 references Messier-
Eram Service Bulletin 631-32-110, dated August 31, 1994, for 
additional inspection instructions.

    (1) If no discrepancies are detected, repeat this inspection at 
intervals not to exceed 7 days.
    (2) If any discrepancies are detected, prior to further flight, 
correct them in accordance with the service bulletin.
    (b) Within 300 hours time-in-service after the effective date of 
this AD, perform a boroscope (endoscope) inspection to detect cracks 
of the MLG leg-to-aircraft rear hinge pin, in accordance with ATR 
Service Bulletin ATR72-32-1028, dated September 1, 1994.

    Note 3: ATR Service Bulletin ATR72-32-1028 references Messier-
Eram Service Bulletin 631-32-110, dated August 31, 1994, for 
additional inspection instructions.

    (1) If no crack is detected, repeat this inspection at intervals 
not to exceed 300 hours time-in-service.
    (2) If any crack is detected, prior to further flight, replace 
the hinge pin in accordance with the service bulletin.
    (c) Within 6 months after the effective date of this AD, perform 
a one-time ultrasonic inspection of the MLG aft hinge pins to 
determine if the pin is free of material defects, in accordance with 
ATR Service Bulletin ATR72-32-1029, dated November 4, 1994.

    Note 4: ATR Service Bulletin ATR72-32-1029 references Messier-
Eram Service Bulletin 631-32-111, dated October 14, 1994, for 
additional inspection instructions.

    (1) If the results of the inspection (echo percentage) are 
within the limits specified in the service bulletin, no further 
action is required by this AD, and the inspections required by 
paragraph (a) and (b) of this AD may be terminated.

    (2) If the results of the inspection are outside the limits 
specified in the service bulletin, prior to further flight, replace 
the pin with a new pin in accordance with the service bulletin. 
After such replacement, no further action is required by this AD, 
and the inspections required by paragraph (a) and (b) of this AD may 
be terminated.

    (d) 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 5: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Standardization Branch, ANM-113.

    (e) 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.

    (f) The inspections and replacement shall be done in accordance 
with ATR Service Bulletin ATR72-32-1028, dated September 1, 1994; 
and ATR Service Bulletin ATR72-32-1029, dated November 4, 1994. This 
incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Copies may be obtained from Aerospatiale, 316 Route de Bayonne, 
31060 Toulouse, Cedex 03, France. Copies may be inspected at the 
FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington; or at the Office of the Federal Register, 800 North 
Capitol Street NW., suite 700, Washington, DC.

    (g) This amendment becomes effective on June 28, 1995.

    Issued in Renton, Washington, on June 1, 1995.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.

[FR Doc. 95-13891 Filed 6-12-95; 8:45 am]
BILLING CODE 4910-13-U