[Federal Register Volume 85, Number 115 (Monday, June 15, 2020)]
[Rules and Regulations]
[Pages 36145-36148]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-12821]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2019-1008; Project Identifier AD-2019-00110-P;
Amendment 39-21142; AD 2020-12-07]
RIN 2120-AA64
Airworthiness Directives; Hamilton Sundstrand Corporation
Propellers
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain Hamilton Sundstrand Corporation (Hamilton Sundstrand) 54H60
model propellers. This AD was prompted by the failure of a propeller
blade that resulted in the loss of the airplane. This AD requires
initial and repetitive eddy current inspections (ECIs) of the affected
propeller blades and replacement of the propeller blades that fail the
inspection. The FAA is issuing this AD to address the unsafe condition
on these products.
DATES: This AD is effective July 20, 2020.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of July 20,
2020.
ADDRESSES: For service information identified in this final rule,
contact Hamilton Sundstrand, 1 Hamilton Road, Windsor Locks, CT 06096-
1010, United States; phone: (877) 808-7575; email: [email protected]. You
may view this service information at the FAA, Airworthiness Products
Section, Operational Safety Branch, 1200 District Avenue, Burlington,
MA 01803. For information on the availability of this material at the
FAA, call 781-238-7759. It is also available on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2019-
1008.
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-2019-
1008; or in person at Docket Operations between 9 a.m. and 5 p.m.,
Monday
[[Page 36146]]
through Friday, except Federal holidays. The AD docket contains this
final rule, any comments received, and other information. The address
for Docket Operations is U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE, Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Maureen Maisttison, Aerospace
Engineer, Boston ACO Branch, FAA, 1200 District Avenue, Burlington, MA
01803; phone: 781-238-7076; fax: 781-238-7199; email:
[email protected].
SUPPLEMENTARY INFORMATION:
Discussion
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to certain Hamilton
Sundstrand 54H60 model propellers. The NPRM published in the Federal
Register on January 28, 2020 (85 FR 4916). The NPRM was prompted by a
report of the separation of a 54H60 model propeller blade installed on
a United States Marine Corps Reserve (USMCR) KC-130T airplane during a
flight in July 2017.
The USMCR investigation of this event revealed the Hamilton
Sundstrand 54H60 model propeller blade separated due to corrosion
pitting and a resultant intergranular radial crack that was not
corrected at the last propeller overhaul. From this intergranular
crack, a fatigue crack initiated and grew under service loading until
the Hamilton Sundstrand 54H60 model propeller blade could no longer
sustain the applied loads and ultimately the blade separated. The
separation of the blade resulted in the loss of the airplane and 17
fatalities. The investigation further revealed that 54H60 model
propeller blades manufactured before 1971 are susceptible to cracks of
the propeller blade in the area of the internal taper bore. The
applicability of this AD is therefore limited to those Hamilton
Sundstrand 54H60 model propellers blades with a blade serial number
below 813320, which are those propeller blades manufactured before
1971.
The NPRM proposed to require initial and repetitive ECIs of the
affected propeller blades and removal from service of any blades that
fail these inspections. Propeller blade taper bore cracks, if not
detected, could result in failure of the propeller blade, blade
separation, and loss of the airplane. The FAA is issuing this AD to
address the unsafe condition on these products.
Comments
The FAA gave the public the opportunity to participate in
developing this final rule. The FAA received one comment, from Lockheed
Martin Aeronautics Company (LMAC). The following presents the FAA's
response.
Comment on Cause of Propeller Blade Separation
LMAC commented that the Discussion section of the NPRM indicated
that the propeller blade separated from the KC-130T airplane as the
result of corrosion that was not corrected at the last propeller
overhaul. LMAC noted that the investigation completed by the U.S. Navy
and the U.S. Air Force concluded that the separation was a result of a
fatigue crack which grew under service loading until the blade could no
longer sustain the applied loads.
The FAA revised the Discussion section of this final rule to state
that the investigation concluded that corrosion pitting and a resultant
intergranular radial crack was not corrected at the last propeller
overhaul. From this intergranular crack, a fatigue crack initiated and
grew under service loading until the Hamilton Sundstrand 54H60 model
propeller blade could no longer sustain the applied loads and
ultimately the blade separated. No change to this AD is required.
Comment on Difference in Compliance Time
LMAC commented that the compliance time in paragraphs (g)(1) and
(2) of the NPRM differs from the time recommended by LMAC in its two
applicable Alert Service Bulletins (ASBs): AV382-61-011, dated October
3, 2019, for all ``382 models'' (excluding the 382J) and 88/SB-723,
dated November 6, 2019, for L-188 Electra aircraft types. LMAC has
recommended that its customers comply with the Hamilton Sundstrand ASB
54H60-61-A154, dated August 26, 2019, within 90 days of receipt of the
applicable aircraft-type LMAC ASB. LMAC stated that this 90-day
compliance time was based on an aircraft-level risk assessment that
considered the consequence of loss of the propeller and the probability
of occurrence based on the reported cases of intergranular cracking of
the blade.
The FAA applied Advisory Circular (AC) 39-8, ``Continued
Airworthiness Assessments of Powerplant and Auxiliary Power Unit
Installations of Transport Category Airplanes,'' dated September 8,
2003 (``AC 39-8'') to identify the unsafe condition and to assess the
risk for propellers installed in transport aircraft. The FAA's risk
assessment for the Hamilton Sundstrand 54H60 propeller affected by this
AD did not support the compliance interval proposed by LMAC in its
ASBs. The FAA's risk assessment did not justify mandating that all
blades be inspected within 90 days, per the LMAC recommendation. No
change to this AD is required.
Comment on Relationship Between Unsafe Condition, Overhaul Period, and
Blade Cracking
LMAC commented that the severity of this ``hazard/unsafe
condition'' is not influenced by the overhaul period and there is no
known correlation between time since overhaul and probability of
intergranular cracking.
The FAA agrees that the severity of this unsafe condition is not
influenced by the overhaul period and there is no known correlation
between time since overhaul and probability of intergranular cracking.
There is little established knowledge of this type of intergranular
crack initiation and growth in this aluminum alloy, although an
investigation has been underway for 2 years. However, the FAA has
determined that since corrosion occurs regardless of whether the
propeller is in service and corrosion has been discovered in blades
exhibiting intergranular cracks, the appropriate compliance time uses
calendar time after the effective date of this AD, based on the time of
the last overhaul.
This AD employs risk-based inspections by placing priority on
inspecting blades that have higher calendar time since their last
overhaul because these blades have a higher probability of corrosion.
In most cases, corrosion has been found to exist in conjunction with
intergranular cracking. Moreover, this AD imposes a mandatory reporting
requirement for cracked blades and the FAA expects that such blades
will be subject to additional metallurgical examinations intended to
identify factors influencing intergranular cracking. The FAA may
consider further rulemaking action on this unsafe condition, depending
on the results of these examinations. No change to this AD is required.
Conclusion
The FAA reviewed the relevant data, considered the comments
received, and determined that air safety and the public interest
require adopting this final rule as proposed except for minor editorial
changes. These minor changes:
Are consistent with the intent that was proposed in the
NPRM for addressing the unsafe condition; and
[[Page 36147]]
Do not add any additional burden upon the public than was
already proposed in the NPRM.
Related Service Information Under 1 CFR Part 51
The FAA reviewed Hamilton Sundstrand Corporation ASB 54H60-61-A154,
dated August 26, 2019. The ASB describes procedures for performing an
ECI of the propeller blade taper bore. This service information is
reasonably available because the interested parties have access to it
through their normal course of business or by the means identified in
the ADDRESSES section.
Interim Action
The FAA considers this AD interim action. The root cause of the
54H60 model propeller blade separation is still under investigation.
The FAA may consider further rulemaking action.
Costs of Compliance
The FAA estimates that this AD affects 212 propellers installed on
53 aircraft of U.S. registry.
The FAA estimates the following costs to comply with this AD:
Estimated Costs
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Cost per Cost on U.S.
Action Labor cost Parts cost product operators
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ECI of propeller................... 8 work-hours x $85 per hour $700 $1,380 $292,560
= $680.
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The FAA estimates the following costs to do any necessary
replacements that would be required based on the results of the
inspection. The FAA has no way of determining the number of aircraft
that might need these replacements:
On-Condition Costs
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Cost per
Action Labor cost Parts cost product
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Replace blade.............................. 1 work-hour x $85 per hour = $85... $63,500 $63,585
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Paperwork Reduction Act
A federal agency may not conduct or sponsor, and a person is not
required to respond to, nor shall a person be subject to a penalty for
failure to comply with a collection of information subject to the
requirements of the Paperwork Reduction Act unless that collection of
information displays a currently valid OMB Control Number. The OMB
Control Number for this information collection is 2120-0056. Public
reporting for this collection of information is estimated to be
approximately 1 hour per response, including the time for reviewing
instructions, searching existing data sources, gathering and
maintaining the data needed, completing and reviewing the collection of
information. All responses to this collection of information are
mandatory. Send comments regarding this burden estimate or any other
aspect of this collection of information, including suggestions for
reducing this burden to: Information Collection Clearance Officer,
Federal Aviation Administration, 10101 Hillwood Parkway, Fort Worth, TX
76177-1524.
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.
Regulatory Findings
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 above, I certify that this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866,
(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
reference, Safety.
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
0
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]
0
2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive (AD):
2020-12-07 Hamilton Sundstrand Corporation: Amendment 39-21142;
Docket No. FAA-2019-1008; Project Identifier AD-2019-00110-P.
(a) Effective Date
This AD is effective July 20, 2020.
(b) Affected ADs
None.
(c) Applicability
This AD applies to all Hamilton Sundstrand Corporation (Hamilton
[[Page 36148]]
Sundstrand) model 54H60 propellers with a blade having a serial
number (S/N) below S/N 813320.
(d) Subject
Joint Aircraft System Component (JASC) Code 6111, Propeller
Blade Section.
(e) Unsafe Condition
This AD was prompted by the separation of a propeller blade that
resulted in the loss of an airplane and 17 fatalities. The FAA is
issuing this AD to detect cracking in the propeller blade taper
bore. The unsafe condition, if not addressed, could result in
failure of the propeller blade, blade separation, and loss of the
airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Required Actions
(1) For affected propellers identified in Planning Information,
paragraph 1.E.(1), of Hamilton Sundstrand Corporation Alert Service
Bulletin (ASB) 54H60-61-A154, dated August 26, 2019 (``the ASB''),
perform an eddy current inspection (ECI) of all blades installed on
the propeller within one year or 500 flight hours after the
effective date of this AD, whichever occurs first.
(2) For affected propellers identified in Planning Information,
paragraph 1.E.(2), of the ASB, perform an ECI of all blades
installed on the propeller within two years or 1,000 flight hours
after the effective date of this AD, whichever occurs first.
(3) Perform the ECI of the affected propeller blades using the
Accomplishment Instructions, paragraph 3.C. of the ASB.
(4) If any propeller blade fails any inspection required by this
AD, based on the criteria in paragraph 3.C. of the ASB, remove the
blade from service and replace with a blade eligible for
installation prior to the next flight.
(5) For all affected propellers, repeat the inspection required
by paragraphs (g)(1) through (4) of this AD at intervals not
exceeding 3 years or 1,500 flight hours, whichever comes first,
after the previous inspection.
(6) Report the results of the ECI required by paragraphs (g)(1)
through (5) of this AD in accordance with the Accomplishment
Instructions, paragraph 3.C.(6) of the ASB.
(h) Installation Prohibition
After the effective date of this AD, do not install any Hamilton
Sundstrand propeller blades having an S/N below 813320 on any
propeller, unless the blade has first passed the inspection required
by this AD. After the effective date of this AD, do not install any
propeller assemblies with affected propeller blades onto any
aircraft unless the affected propeller blades have passed the
inspection required by paragraph (g) of this AD.
(i) Paperwork Reduction Act Burden Statement
A federal agency may not conduct or sponsor, and a person is not
required to respond to, nor shall a person be subject to a penalty
for failure to comply with a collection of information subject to
the requirements of the Paperwork Reduction Act unless that
collection of information displays a currently valid OMB Control
Number. The OMB Control Number for this information collection is
2120-0056. Public reporting for this collection of information is
estimated to be approximately 1 hour per response, including the
time for reviewing instructions, searching existing data sources,
gathering and maintaining the data needed, completing and reviewing
the collection of information. All responses to this collection of
information are mandatory. Send comments regarding this burden
estimate or any other aspect of this collection of information,
including suggestions for reducing this burden to: Information
Collection Clearance Officer, Federal Aviation Administration, 10101
Hillwood Parkway, Fort Worth, TX 76177-1524.
(j) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Boston ACO Branch, FAA, has the authority to
approve AMOCs for this AD, if requested using the procedures found
in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request
to your principal inspector or local Flight Standards District
Office, as appropriate. If sending information directly to the
manager of the certification office, send it to the attention of the
person identified in paragraph (k) of this AD.
(2) Before using any approved AMOC, notify your appropriate
principal inspector, or lacking a principal inspector, the manager
of the local flight standards district office/certificate holding
district office.
(k) Related Information
For more information about this AD, contact Maureen Maisttison,
Aerospace Engineer, Boston ACO Branch, FAA, 1200 District Avenue,
Burlington, MA 01803; phone: 781-238-7076; fax: 781-238-7199; email:
[email protected].
(l) Material Incorporated by Reference
(1) The Director of the Federal Register approved the
incorporation by reference (IBR) of the service information listed
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) You must use this service information as applicable to do
the actions required by this AD, unless the AD specifies otherwise.
(i) Hamilton Sundstrand Corporation (Hamilton Sundstrand) Alert
Service Bulletin 54H60-61-A154, dated August 26, 2019.
(ii) [Reserved]
(3) For Hamilton Sundstrand service information identified in
this AD, contact Hamilton Sundstrand, 1 Hamilton Road, Windsor
Locks, CT 06096-1010, United States; phone: (877) 808-7575; email:
[email protected].
(4) You may view this service information at the FAA,
Airworthiness Products Section, Operational Safety Branch, 1200
District Avenue, Burlington, MA 01803. For information on the
availability of this material at the FAA, call 781-238-7759.
(5) You may view this service information that is incorporated
by reference at the National Archives and Records Administration
(NARA). For information on the availability of this material at
NARA, email: [email protected], or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.
Issued on June 3, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification
Service.
[FR Doc. 2020-12821 Filed 6-12-20; 8:45 am]
BILLING CODE 4910-13-P