DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2020-0912; Product Identifier 2015-SW-071-AD]
Airworthiness Directives; Airbus Helicopters
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
SUMMARY: The FAA proposes to supersede airworthiness directive
20-05 for Societe Nationale Industrielle Aerospatiale (now Airbus
Helicopters) Model AS-350 and AS-355 series helicopters. AD 82-20-05
requires inspecting and establishing a life limit for the tail rotor
(TR) drive shaft bearing (bearing). Since the FAA issued AD 82-20-05,
inconsistencies have been identified between inspections and
maintenance actions required by ADs and inspections and maintenance
actions specified in the applicable maintenance manual. This proposed
AD would require replacing certain part-numbered TR bearings with one
part-numbered bearing and repetitively inspecting one part-numbered
bearing. The actions of this proposed AD are intended to address an
unsafe condition on these products.
DATES: The FAA must receive comments on this proposed AD by November
ADDRESSES: You may send comments by any of the following methods:
Federal eRulemaking Docket: Go to https://www.regulations.gov. Follow
online instructions for sending your comments electronically.
Mail: Send comments to the U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE, Washington, DC 20590-0001.
Hand Delivery: Deliver to the "Mail" address between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
Examining the AD Docket
You may examine the AD docket on the internet at https://www.regulations.
gov by searching for and locating Docket No. FAA-2020-0912;
or in person at Docket Operations between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays. The AD docket contains
this proposed AD, the European Aviation Safety Agency (now European
Union Aviation Safety Agency) (EASA) AD, any comments received, and
other information. The street address for Docket Operations is listed
above. Comments will be available in the AD docket shortly after
For service information identified in this proposed rule, contact
Airbus Helicopters, 2701 N. Forum Drive, Grand Prairie, TX 75052;
telephone 972-641-0000 or 800-232-0323; fax 972-641-3775; or at https://
www.airbus.com/helicopters/services/technical-support.html. You may
view the referenced service information at the FAA, Office of the
Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-321,
Fort Worth, TX 76177.
FOR FURTHER INFORMATION CONTACT: David Hatfield, Aviation Safety
Engineer, Safety Management Section, Rotorcraft Standards Branch, FAA,
10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone 817-222-5116;
The FAA invites you to participate in this rulemaking by submitting
written comments, data, or views. The most helpful comments reference
specific portion of the proposal, explain the reason for any
recommended change, and include supporting data. To ensure the docket
does not contain duplicate comments, commenters should send only one
copy of written comments, or if comments are filed electronically,
commenters should submit only one time.
Except for Confidential Business Information as described in the
following paragraph, and other information as described in 14 CFR
11.35, the FAA will file in the docket all comments received, as well
as a report summarizing each substantive public contact with FAA
personnel concerning this proposed rulemaking. Before acting on this
proposal, the FAA will consider all comments received on or before the
closing date for comments. The FAA will consider comments filed after
the comment period has closed if it is possible to do so without
incurring expense or delay. The FAA may change this proposal in light
of the comments received.
Confidential Business Information
Confidential Business Information (CBI) is commercial or financial
information that is both customarily and actually treated as private by
its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552),
CBI is exempt from public disclosure. If your comments responsive to
this NPRM contain commercial or financial information that is
customarily treated as private, that you actually treat as private, and
that is relevant or responsive to this NPRM, it is important that you
clearly designate the submitted comments as CBI. Please mark each page
of your submission containing CBI as "PROPIN." The FAA will treat
such marked submissions as confidential under the FOIA, and they will
not be placed in the public docket of this NPRM. Submissions containing
CBI should be sent to David Hatfield, Aviation Safety Engineer, Safety
Management Section, Rotorcraft Standards Branch, FAA, 10101 Hillwood
Pkwy., Fort Worth, TX 76177; telephone: 817-222-5116; email
email@example.com. Any commentary that the FAA receives which is
not specifically designated as CBI will be placed in the public docket
for this rulemaking.
The FAA issued AD 82-20-05, Amendment 39-4466 (47 FR 43018,
September 30, 1982) ("AD 82-20-05") for Societe Nationale
Industrielle Aerospatiale (now Airbus Helicopters) Model AS-350 and AS-
355 series helicopters. AD 82-20-05 requires repetitively inspecting
bearing part number (P/N) SKF 6007-2RS1MT47CA and P/N AS704A33.651.010
to determine if the perpendicularity of the bearing relative to the
shaft is within certain limits. AD 82-20-05 also establishes a life
limit of 1,200 hours time-in-service (TIS) for the bearing and rubber
AD 82-20-05 was prompted by reports of four accidents due to
failure of the drive shaft on Aerospatiale (now Airbus Helicopters) AS-
350 helicopters, and the resulting corrective actions required through
ADs issued by the French Airworthiness Authority. The actions in AD 82-
20-05 are intended to prevent failure or seizure of a bearing.
Actions Since AD 82-20-05 Was Issued
Since the FAA issued AD 82-20-05, EASA, which is the Technical
Agent for the Member States of the European Union, issued EASA AD No.
2015-0195, dated September 23, 2015 (EASA AD 2015-0195), to correct an
unsafe condition for Airbus Helicopters Model AS 350 B, BA, BB, B1, B2,
B3, and D, and AS 355 E, F, F1, F2, N, and NP helicopters with certain
part-numbered bearings installed. EASA advises that after
inconsistencies were identified between inspections and maintenance
actions required by French Civil Aviation Authority ADs and EASA ADs,
Airbus Helicopters issued service information to specify replacing four
different part-numbered bearings with one bearing P/N 593404 (also
listed as manufacturer part number (MP/N) 704A33-651-181) and to
provide inspection procedures for the new bearing. Accordingly, EASA AD
2015-0195 retains the inspections for the older design bearings,
requires replacing the bearings with the new bearings, and requires
repetitive inspections for the new bearings.
These helicopters have been approved by EASA and are approved for
operation in the United States. Pursuant to the FAA's bilateral
agreement with the European Union, EASA has notified the FAA about the
unsafe condition described in its AD. The FAA is proposing this AD
after evaluating all known relevant information and determining that an
unsafe condition is likely to exist or develop on other products of the
same type designs.
Related Service Information
The FAA reviewed Airbus Helicopters Alert Service Bulletin (ASB)
No. AS355-01.00.57, Revision 2, dated January 19, 2016, for Model AS355
helicopters, and ASB AS350-01.00.70, Revision 1, dated September 21,
2015, for Model AS350 helicopters. The service information describes
procedures for inspecting bearing P/N 593404 or MP/N 704A33-651-181 for
position, condition, and wear. This service information also advises
customers that older designed bearings are not fit for flight, and
specifies replacing the older designed bearings with new bearing P/N
593404 or MP/N 704A33-651-181. This service information also references
procedures for repetitively inspecting the newer bearings.
Proposed AD Requirements
This proposed AD would require within 100 hours TIS, and thereafter
at intervals not to exceed 165 hours TIS, for helicopters with bearing
P/N 593404 or MP/N 704A33-651-181 installed, inspecting each bearing
holder damper bushing for wear, a crack, tears, and play between each
bushing and support plate. This proposed AD would require inspecting
each bearing holder for a crack, fretting, and corrosion around the
attachment holes. This proposed AD would also require inspecting each
rubber sleeve for rotation, crazing, play between the inner races and
the rubber sleeve, and lack of integrity of the elastomer. Depending on
the inspection results, this proposed AD would require removing certain
parts from service. This proposed AD would also require, within 100
hours TIS, making a mark with white paint on the rubber sleeves and on
the shaft, and for helicopters with affected TR drive shaft bearings P/
N 6007-2RS1MT47CA, P9107NPP7, 83A851BC3, or 83A851B-1C3, or MP/N
704A33-651-010, 704A33-651-111, or 704A33-651-143 installed, removing
the affected bearings from service and replacing with bearing P/N
593404 or MP/N 704A33-651-181. This proposed AD would prohibit
installing certain bearings on any helicopter.
Differences Between This Proposed AD and the EASA AD
The EASA AD requires replacing the older design bearings within 10
months, while this proposed AD would require replacing the bearings
within 100 hours TIS. The EASA AD applies to Model AS350BB helicopters;
this proposed AD would not as this model helicopter is not FAA type-
certificated. Finally, this proposed AD would apply to Model AS350C and
AS350D1 helicopters as they have the same bearings installed, and the
EASA AD does not.
Costs of Compliance
The FAA estimates that this proposed AD would affect 915
helicopters of U.S. Registry. The FAA estimates that operators may
incur the following costs in order to comply with this proposed AD.
Labor costs are estimated at $85 per work-hour.
For Model AS350 B, BA, B1, B2, B3, and C helicopters, inspecting
the bearings would take about 2.5 work-hours, for an estimated cost of
$213 per helicopter per inspection cycle.
Replacing each bearing with a single part-numbered bearing would
take about 2.5 work-hours and parts would cost about $1,225, for a cost
of $1,438 per helicopter.
For Model AS350 D, D1, and AS355-series helicopters, inspecting the
bearings would take about 3 work-hours, for a cost of $255 per
helicopter per inspection cycle.
Replacing each bearing with a single part-numbered bearing would
take about 3 work-hours and parts would cost about $1,470, for a cost
of $1,725 per helicopter.
Making a mark with white paint on the rubber sleeves and shaft
would take a minimal amount of time and have a nominal parts cost.
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, section 106, describes the
authority of the FAA Administrator. Subtitle VII: Aviation Programs,
describes in more detail the scope of the Agency's authority.
The FAA is issuing this rulemaking under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701: General requirements.
Under that section, Congress charges the FAA with promoting safe flight
of civil aircraft in air commerce by prescribing regulations for
practices, methods, and procedures the Administrator finds necessary
for safety in air commerce. This regulation is within the scope of that
authority because it addresses an unsafe condition that is likely to
exist or develop on products identified in this rulemaking action.
The FAA determined that this proposed AD would not have federalism
implications under Executive Order 13132. This proposed AD would not
have a substantial direct 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.
For the reasons discussed, I certify this proposed regulation:
1. Is not a "significant regulatory action" under Executive Order
2. Will not affect intrastate aviation in Alaska, 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.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
The Proposed Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA proposes to amend 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. The FAA amends Sec. 39.13 by:
a. Removing Airworthiness Directive (AD) 82-20-05, Amendment 39-4466
(47 FR 43018, September 30, 1982); and
b. Adding the following new AD: