[Federal Register: September 18, 2003 (Volume 68, Number 181)]
[Proposed Rules]
[Page 54686-54688]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr18se03-19]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2002-SW-45-AD]
RIN 2120-AA64
Airworthiness Directives; Eurocopter France Model AS332C, L, and
L1 Helicopters
AGENCY: Federal Aviation Administration, DOT.
ACTION: Supplemental notice of proposed rulemaking (SNPRM); reopening
of comment period.
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SUMMARY: This document revises an earlier proposed airworthiness
directive (AD) for the specified Eurocopter France (Eurocopter) model
helicopters that would have required, for bevel gears with more than
6,600 hours time-in-service (TIS), inspecting the bevel gear for a
crack using a borescope within 50 hours TIS, and thereafter at
intervals not to exceed 150 hours TIS. That proposal was prompted by a
crack that was detected on a bevel gear during a main gearbox teardown
inspection. This action revises the proposed rule by requiring the
borescope inspection at intervals not to exceed 150 hours TIS or 1,000
torque variation cycles (cycles) for helicopter operations involving
frequent torque variations, whichever occurs first. This action is
prompted by an analysis of the crack growth rate, which indicates that
the growth rate is higher in helicopters with operations involving a
torque variation frequency of 4 or more cycles per hour. The actions
specified by this proposed AD are intended to detect a bevel gear crack
and prevent failure of the bevel gear,
[[Page 54687]]
loss of torque to the main rotor system, and subsequent loss of control
of the helicopter.
DATES: Comments must be received on or before November 17, 2003.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Office of the Regional Counsel, Southwest Region,
Attention: Rules Docket No. 2002-SW-45-AD, 2601 Meacham Blvd., Room
663, Fort Worth, Texas 76137. You may also send comments electronically
to the Rules Docket at the following address: 9-asw-adcomments@faa.gov.
Comments may be inspected at the Office of the Regional Counsel between
9 a.m. and 3 p.m., Monday through Friday, except Federal holidays.
FOR FURTHER INFORMATION CONTACT: Uday Garadi, Aviation Safety Engineer,
FAA, Rotorcraft Directorate, Safety Management Group, Fort Worth, Texas
76193-0110, telephone (817) 222-5123, fax (817) 222-5961.
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 should 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 document 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 mailed
comments submitted in response to this proposal must submit a self-
addressed, stamped postcard on which the following statement is made:
``Comments to Docket No. 2002-SW-45-AD.'' The postcard will be date
stamped and returned to the commenter.
Discussion
A proposal to amend 14 CFR part 39 to add an AD for the specified
Eurocopter model helicopters was published in the Federal Register on
December 31, 2002 (67 FR 79893). That NPRM would have required for
bevel gears with more than 6,600 hours TIS, inspecting the bevel gear
for cracks using a borescope within 50 hours TIS, and thereafter at
intervals not to exceed 150 hours TIS. If a crack were found in the
bevel gear, replacing the bevel gear would be required. That NPRM was
prompted by a crack that was detected on a bevel gear during a main
gearbox teardown inspection. That condition, if not corrected, could
result in failure of the bevel gear, loss of torque to the main rotor
system, and subsequent loss of control of the helicopter.
Since issuing that NPRM, the FAA discovered that certain part
numbered bevel gears were omitted from the applicability and one was
incorrectly stated in that NPRM. Also, the manufacturer has revised the
service information to introduce the new inspection interval of 1,000
cycles for helicopter operations involving a torque application
frequency of more than 4 cycles per hour for helicopters that conduct
external load operations involving more frequent torque applications.
Additionally, we inadvertently included Model AS332C1 helicopters in
the ``Applicability'' section of the NPRM--those model helicopters are
not on the U.S. Registry. Finally, the DGAC has issued a revised AD for
helicopters operated in France.
This SNPRM revises the NPRM to:
[sbull] Correct the basic bevel gear part number (P/N) stated in
the ``Applicability'' of the NPRM to state ``332A32-2181-00'';
[sbull] Add bevel gear P/Ns 332A32-2181-01 and -08 to the
``Applicability'';
[sbull] Delete the Model AS332C1 helicopters from the
``Applicability'';
[sbull] Incorporate the latest Eurocopter Alert Telex and
references the latest DGAC AD;
[sbull] Require the repetitive inspection at intervals not to
exceed 150 hours TIS or 1,000 torque cycles, whichever occurs first;
and
[sbull] Exclude from the ``Applicability'' any main gearbox
(regardless of the P/N of the main reduction gear module or bevel gear)
overhauled after December 31, 2002, and any part number inspected in
accordance with AS332 letter to Repair Stations No. 183 or repaired in
accordance with Repair Sheet (F.R.) 332A32-2181-ZA or 331A32-3110-ZA.
Since this change expands the scope of the originally proposed
rule, we have determined that it is necessary to reopen the comment
period to provide additional opportunity for public comment.
The Direction Generale De L'Aviation Civile (DGAC), the
airworthiness authority for France, notified the FAA that an unsafe
condition may exist on Eurocopter Model AS332C, C1, L, and L1
helicopters, equipped with main gearbox main reduction gear modules,
part numbers (P/N) 332A32-2027-00 or 332A32-2026-00, containing bevel
gears, P/N 332A32-2181-00, -01, -02, -03, or -04, or 331A32-3110-07, -
09, or -19. The DGAC advises that borescope inspections of the bevel
gear are necessary to detect cracks.
Eurocopter has issued Alert Telex No. 05.00.58 R2, dated February
3, 2003, which indicates that as a result of metal particles found on
the chip detector of the main gearbox sump on a helicopter, further
investigation has revealed a longitudinal crack that grows lengthwise
in the shaft, up to the combiner gear, in the bevel gear where the ring
retains the pinion toe bearing. The alert telex specifies inspecting
the bevel gear for cracks using a borescope, pending the result of the
investigation into the cause of the fatigue crack initiation currently
being conducted in France. The DGAC classified this alert telex as
mandatory and issued AD 2002-424-081(A) R2, dated March 19, 2003, to
ensure the continued airworthiness of these helicopters in France.
On July 10, 2002, the FAA issued a new version of 14 CFR part 39
(67 FR 47997, July 22, 2002), which governs the FAA's AD system. The
regulation now includes material that relates to altered products,
special flight permits, and alternative methods of compliance. Because
we have now included this material in part 39, we no longer need to
include it in each individual AD. Therefore, Note 1 of the original
NPRM has been removed and paragraph (c) has been modified in this
SNPRM.
The FAA estimates that 4 helicopters of U.S. registry would be
affected by this proposed AD, that it would take approximately 4 work
hours per helicopter to accomplish the inspections and 16 work hours
per helicopter to replace the bevel gear. The average labor rate is $65
per work hour. Required parts would cost approximately $31,372. Based
on these figures, the total cost impact of the proposed AD on U.S.
operators is estimated to be $130,688, assuming that upon the first
inspection a crack is detected and the bevel gear will be replaced.
The regulations proposed herein would not have a substantial direct
[[Page 54688]]
effect 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, it
is determined that this proposal would not have federalism implications
under Executive Order 13132.
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 adding a new airworthiness directive
to read as follows:
Eurocopter France: Docket No. 2002-SW-45-AD.
Applicability: Model AS332C, L, and L1 helicopters, with main
gearbox bevel gear (bevel gear), part numbers (P/N) 332A32-2027-00
or 332A32-2026-00, containing bevel gears, P/N 332A32-2181-00, -01,
-02, -03, or -04, or 331A32-3110-07, -08, -09, or -19, installed,
certificated in any category. This AD does not apply to:
[sbull] Main gearboxes that were overhauled after December 31,
2002;
[sbull] Parts inspected in accordance with AS332 letter to
Repair Stations No. 183; or
[sbull] Parts repaired in accordance with Repair Sheet (F.R.)
332A32-2181-ZA or 331A32-3110-ZA.
Compliance: Required as indicated, unless accomplished
previously.
To detect a bevel gear crack and prevent failure of the bevel
gear, loss of torque to the main rotor system, and subsequent loss
of control of the helicopter, accomplish the following:
(a) For bevel gears that have more than 6,600 hours time-in-
service (TIS), within 50 hours TIS and thereafter at intervals not
to exceed 150 hours TIS, or at intervals not to exceed 1,000
frequent torque variation cycles, whichever occurs first, inspect
for a crack using a boroscope in accordance with the Operational
Procedure, paragraph 2.B.1. and 2.B.2. of Eurocopter Telex No.
05.00.58 R2, dated February 3, 2003. A frequent torque variation
cycle is each landing or external load operation beginning at the
point when there are 4 or more landings, or 4 or more external load
operations, or any combination of 4 or more landings and external
load operations in any 60 minute time period, and ending when any
combination of landings and external load operations is less than 4
in any 60 minute time period.
(b) If a crack is found in the bevel gear, before further
flight, replace the bevel gear with an airworthy bevel gear.
(c) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Contact the Safety Management Group, Rotorcraft Directorate, FAA,
for information about previously approved alternative methods of
compliance.
Note: The subject of this AD is addressed in Direction Generale
De L'Aviation Civile (France) AD 2002-424-081(A) R2, dated March 19,
2003.
Issued in Fort Worth, Texas, on September 8, 2003.
David A. Downey,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 03-23835 Filed 9-17-03; 8:45 am]
BILLING CODE 4910-13-P