DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2018-0613; Product Identifier 2018-SW-041-AD; Amendment
39-19391; AD 2018-18-12]
Airworthiness Directives; Airbus Helicopters
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; request for comments.
SUMMARY: We are adopting a new airworthiness directive (AD) for
Helicopters Model AS350B, AS350B1, AS350B2, AS350B3, and AS350BA
helicopters with a Pall Aerospace Corporation inlet barrier filter
(IBF) element. This AD requires revising the Rotorcraft Flight Manual
Supplement to prohibit operating a helicopter with an IBF element in wet
and replacing the IBF element if wet. This AD is prompted by a forced
landing after an engine flameout. The actions of this AD are intended
to address an unsafe condition on these products.
DATES: This AD becomes effective September 25, 2018.
We must receive comments on this AD by November 9, 2018.
ADDRESSES: You may send comments by any of the following methods:
Federal eRulemaking Docket: Go to http://www.regulations.gov. Follow the
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 http://www.regulations.gov
by searching for and locating Docket No. FAA-2018-
0613; 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 AD, any incorporated-by-reference service information, the
economic evaluation, any comments received, and other information. The
street address for Docket Operations (telephone 800-647-5527) is in the
ADDRESSES section. Comments will be available in the AD docket shortly
For service information identified in this final rule, contact Pall
Aerospace Corporation, 10540 Ridge Road, Suite 300, Newport Richey,
Florida 34654; telephone 727-514-6491; email email@example.com;
website www.pall.com/aerospace. You may review 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: Todd Jackson, Aerospace Engineer,
Atlanta ACO Branch, Compliance and Airworthiness Division, FAA, 1701
Columbia Ave., College Park, GA 30337, telephone 404-474-5567, email
This AD is a final rule that involves requirements affecting flight
safety, and we did not provide you with notice and an opportunity to
provide your comments prior to it becoming effective. However, we
invite you to participate in this rulemaking by submitting written
comments, data, or views. We also invite comments relating to the
economic, environmental, energy, or federalism impacts that resulted
from adopting this AD. The most helpful comments reference a specific
portion of the AD, 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 them only one time. We will file in the docket all comments that
we receive, as well as a report summarizing each substantive public
contact with FAA personnel concerning this rulemaking during the
comment period. We will consider all the comments we receive and may
conduct additional rulemaking based on those comments.
In June 2017, we received a report of an incident involving an
Airbus Helicopters Model AS350B3 helicopter fitted with an IBF. The
helicopter took off in heavy rain and experienced an engine flameout as
the pilot increased power. The helicopter was less than 10 feet off the
ground when the pilot was forced to land immediately. An inspection
showed that violent water ingestion damaged six axial compressor
blades. During our investigation, the FAA received additional reports
of previous incidents of helicopters equipped with IBFs or induction
filter installations experiencing abnormal engine operations during
The FAA issued Special Airworthiness Information Bulletin SW-17-30,
dated October 13, 2017¹ (SAIB), to warn operators that persistent or
heavy rains may result in the inlet barrier filter media collecting and
retaining water. The SAIB recommended the following to affected owners
¹SAIB SW-17-30, dated October 13, 2017, may be viewed online
Use IBF covers when the rotorcraft is parked or towed
outside, particularly when precipitation is reported in the area;
During the helicopter preflight inspection, visually
inspect the inlet and filter to verify that the inlet and filter medium
are dry and free of accumulated moisture;
If the filter medium has moisture during the preflight
inspection, or if the rotorcraft is operating in heavy precipitation,
open the bypass doors if equipped; and
When operating in precipitation, sudden and rapid power
transients should be avoided whenever practical.
Action Since the SAIB Was Issued
After the SAIB was issued, we continued to investigate this issue
and determined that AD action was necessary for certain Pall
Corporation IBF dry-media filter elements. Filters that have a
hydrophobic coating resist water accumulation, while the dry-media
filters that are the subject of this AD accumulate water. The risk of
engine failure caused by the ingestion of an excessive amount of water
through the IBF element results in an unsafe condition that requires AD
We are issuing this AD because we evaluated all the relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of these same type
Related Service Information
We reviewed Pall Corporation Service Information Letter
CE01301F2SINFOL, Revision A, dated July 15, 2015, which recommends
covering the engine inlet if the helicopter is outside while not
operating. The letter also recommends conducting pre-flight inspections
to ensure the engine inlet is clear of water.
This AD requires, within 30 days, revising the rotorcraft flight
manual supplement by inserting Appendix A of this AD into the
Differences Between This AD and the Service Information
The service information allows for removing water and reinstalling
the IBF element if there is standing water on the engine inlet. This AD
prohibits operation unless the IBF element is dry.
We consider this AD to be an interim action. The design approval
holder is currently developing a modification that will address the
unsafe condition identified in this AD. Once this modification is
developed, approved, and available, we might consider additional
Costs of Compliance
We estimate that this AD will affect 81 helicopters of U.S.
Registry and that labor costs average $85 per work-hour. Based on these
estimates, we expect the following costs:
Incorporating Appendix A of this AD into the rotorcraft
flight manual requires 1 work-hour and no parts for a cost of $85 per
helicopter and $6,885 for the U.S. fleet.
Replacing the inlet barrier filter, if required, requires
2 work-hours and parts cost $3,995 for a cost of $4,165 per filter
FAA's Justification and Determination of the Effective Date
An unsafe condition exists that requires the immediate adoption of
this AD without providing an opportunity for public comments prior to
adoption. The FAA has found that the risk to the flying public
justifies waiving notice and comment prior to adoption of this rule
because the unsafe condition requires corrective action within 30 days.
Therefore, we find good cause that notice and opportunity for prior
public comment are impracticable. In addition, for the reason stated
above, we find that good cause exists for making this amendment
effective in less than 30 days.
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
We are 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
We determined that this AD will not have federalism implications
under Executive Order 13132. This AD will 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 that this AD:
1. Is not a ``significant regulatory action'' under Executive Order
2. Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979);
3. Will not affect intrastate aviation in Alaska to the extent that
it justifies making a regulatory distinction; and
4. 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.
We prepared an economic evaluation of the estimated costs to comply
with this AD and placed it in the AD docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
Adoption of the Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 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 adding the following new airworthiness