[Federal Register Volume 60, Number 55 (Wednesday, March 22, 1995)]
[Proposed Rules]
[Pages 15084-15086]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-6999]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-36-AD]


Airworthiness Directives; Aerospatiale Model ATR72-100 and -200 
Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Supplemental notice of proposed rulemaking; reopening of 
comment period.

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SUMMARY: This document revises an earlier proposed airworthiness 
directive (AD), applicable to certain Model ATR72-100 and -200 series 
airplanes, that would have required a one-time dye penetrant inspection 
to detect cracking in certain hinge pins of the nose landing gear 
(NLG), and replacement of cracked pins with crack-free pins. That 
proposal was prompted by reports of cracking of certain hinge pins in 
the NLG. This action revises the proposed rule by shortening the 
compliance time to perform the inspection of the hinge pins of the NLG. 
The actions specified by this proposed AD are intended to prevent 
collapse of the NLG due to cracking of the hinge pins.

DATES: Comments must be received by May 1, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-36-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: 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:

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 94-NM-36-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. 94-NM-36-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to add an airworthiness directive (AD), applicable to 
certain Aerospatiale Model ATR72-100 and -200 series airplanes, was 
published as a notice of proposed rulemaking (NPRM) in the Federal 
Register on May [[Page 15085]] 18, 1994 (59 FR 25846). That NPRM would 
have required a one-time dye penetrant inspection to detect cracking in 
certain hinge pins in the nose landing gear (NLG), and replacement of 
cracked pins with crack-free pins. That NPRM was prompted by a report 
that cracking has been found on the hinge pins during routine overhaul 
of the NLG. That condition, if not corrected, could result in collapse 
of the NLG due to cracking of the hinge pins.
    Since the issuance of that NPRM, the FAA has received a comment 
from the manufacturer that has caused the FAA to reconsider the 
proposed compliance time to perform the inspection of the hinge pins of 
the NLG. Aerospatiale requests that the proposed compliance time of 
10,000 landings be shortened to 1,000 landings for airplanes that have 
accumulated 10,000 or more total landings, and 1,500 landings for 
airplanes that have accumulated less than 10,000 total landings. 
Aerospatiale suggests that the proposed compliance time may be too long 
for these airplanes to fly with a potential for the NLG to collapse due 
to cracking of the hinge pins. The commenter's suggested compliance 
time would allow older airplanes that are at greater risk to be 
inspected earlier, while newer airplanes that pose a lower risk would 
be inspected later. Further, this staggered compliance time would allow 
the manufacturer additional time to produce an adequate number of 
replacement pins.
    The FAA concurs. The FAA has reconsidered the compliance time for 
performing the inspection of the hinge pins of the NLG and finds that 
the compliance time must be shortened based upon the degree of urgency 
associated with addressing the subject unsafe condition and the 
availability of replacement pins. Therefore, the FAA finds that to 
ensure safety of the fleet, the compliance time for paragraph (a) must 
be shortened. For airplanes that have accumulated 10,000 or more total 
landings, the compliance time has been shortened to 1,000 landings; and 
for airplanes that have accumulated less than 10,000 total landings, 
the compliance time has been shortened to 1,500 landings. (This change 
has necessitated the reitemization of the paragraphs. Paragraphs (b) 
and (c) were formerly identified in the proposal as paragraphs (a)(1) 
and (a)(2).)
    Since this change in the proposed compliance times expands the 
scope of the originally proposed rule, the FAA has determined that it 
is necessary to reopen the comment period to provide additional 
opportunity for public comment.
    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 notice to clarify this requirement.
    The FAA has recently reviewed the figures it has used over the past 
several years in calculating the economic impact of AD activity. In 
order to account for various inflationary costs in the airline 
industry, the FAA has determined that it is necessary to increase the 
labor rate used in these calculations from $55 per work hour to $60 per 
work hour. The economic impact information, below, has been revised to 
reflect this increase in the specified hourly labor rate.
    The FAA estimates that 28 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 6 work 
hours per airplane to accomplish the proposed actions, and that the 
average labor rate is $60 per work hour. Based on these figures, the 
total cost impact of the proposed AD on U.S. operators is estimated to 
be $10,080, or $360 per airplane.
    The total 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.
    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. 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: AEROSPATIALE: Docket 94-NM-36-AD.

    Applicability: Model ATR72-100 and -200 series airplanes 
equipped with hinge pins installed at the nose landing gear (NLG) 
that are manufactured by Nardi, have part number D56867, and have 
serial numbers beginning with the letter ``N''; 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 (e) 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. [[Page 15086]] 
    To prevent collapse of the NLG due to cracking of the hinge 
pins, accomplish the following:
    (a) Perform a dye penetrant inspection to detect cracking in the 
hinge pins of the NLG in accordance with Avions de Transport 
Regional Service Bulletin ATR72-32-1021, dated January 17, 1994, at 
the time specified in either paragraph (a)(1) or (a)(2) or this AD, 
as applicable.
    (1) For airplanes that have accumulated 10,000 total landings or 
more as of the effective date of this AD: Within 1,000 landings 
after the effective date of this AD.
    (2) For airplanes that have accumulated less than 10,000 total 
landings as of the effective date of this AD: Within 1,500 landings 
after the effective date of this AD.
    (b) If no cracking is found, prior to further flight, reinstall 
that hinge pin in accordance with Avions de Transport Regional 
Service Bulletin ATR72-32-1021, dated January 17, 1994.
    (c) If cracking is found, prior to further flight, install a new 
hinge pin or a pin that has been previously inspected and found to 
be crack-free, in accordance with the Avions de Transport Regional 
Service Bulletin ATR72-32-1021, dated January 17, 1994.
    (d) As of the effective date of this AD, no hinge pin 
manufactured by Nardi having part number D56867 and any serial 
number beginning with the letter ``N,'' shall be installed on the 
NLG of any airplane, unless that pin has been previously inspected 
and has been found to be crack-free, in accordance Avions de 
Transport Regional Service Bulletin ATR72-32-1021, dated January 17, 
1994.
    (e) 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.

    (f) 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 March 16, 1995.

Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 95-6999 Filed 3-21-95; 8:45 am]
BILLING CODE 4910-13-U