[Federal Register Volume 60, Number 45 (Wednesday, March 8, 1995)]
[Rules and Regulations]
[Pages 12663-12666]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-5483]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 95-ANE-02; Amendment 39-9170; AD 95-05-03]
Airworthiness Directives; Hamilton Standard 14RF Series, 14SF
Series, and Hamilton Standard/British Aerospace Model 6/5500/F
Propellers
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment supersedes an existing airworthiness directive
(AD), applicable to Hamilton Standard 14RF series, 14SF series, and
Hamilton Standard/British Aerospace 6/5500/F series propellers, that
currently requires a one-time ultrasonic shear wave inspection for
cracks in the propeller blade taper bore. This amendment requires
initial and repetitive ultrasonic shear wave inspections, and a one-
time visual and borescope inspection of the taper bore for corrosion as
a terminating action to the ultrasonic shear wave inspections. This
amendment is prompted by reports of two incidents where a portion of
the propeller blade was lost in flight. The actions specified by this
AD are intended to prevent loss of a propeller blade due to cracks
initiating in the blade taper bore, that can result in possible
aircraft damage, and possible loss of aircraft control.
DATES: Effective March 23, 1995.
The incorporation by reference of the following Hamilton Standard
Alert Service Bulletins (ASB) was approved by the Director of the
Federal Register as of May 2, 1994: ASB's No. 14RF-9-61-A66, No. 14RF-
19-61-A34, No. 14RF-21-61-A53, No. 14SF-61-A73, and No. 6/5500/F-61-
A27, all dated April 18, 1994.
The incorporation by reference of all other Hamilton Standard ASB's
and Service Bulletins listed in this AD is approved by the Director of
the Federal Register as of March 23, 1995.
Comments for inclusion in the Rules Docket must be received on or
before May 8, 1995.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), New England Region, Office of the Assistant Chief
Counsel, Attention: Rules Docket No. 95-ANE-02, 12 New England
Executive Park, Burlington, MA 01803-5299.
The service information referenced in this AD may be obtained from
Hamilton Standard, One Hamilton Road, Windsor Locks, CT 06096-1010;
telephone (203) 654-3610. This information may be examined at the FAA,
New England Region, Office of the Assistant Chief Counsel, Burlington,
MA; or at the Office of the Federal Register, 800 North Capitol Street
NW., suite 700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: Frank Walsh, Aerospace Engineer,
Boston Aircraft Certification Office, FAA, Engine and Propeller
Directorate, 12 New England Executive Park, Burlington, MA 01803-5299;
telephone (617) 238-7158, fax (617) 238-7199.
SUPPLEMENTARY INFORMATION: On April 18, 1994, the Federal Aviation
Administration (FAA) issued airworthiness directive (AD) 94-09-06,
Amendment 39-8894 (59 FR 19127, April 22, 1994), applicable to Hamilton
Standard 14RF series, 14SF series, and Hamilton Standard/British
Aerospace 6/5500/F series propellers, to require an ultrasonic shear
wave inspection of the blade taper bore for cracks, and replacement, if
necessary, with a serviceable propeller blade. That action was prompted
by reports of two incidents where a portion of the propeller blade was
lost in flight. On March 13, 1994, an ATR-42 commuter aircraft
experienced an inflight loss of the right propeller and a portion of
the associated engine gearbox. Later that month, on March 30, 1994, an
Embraer EMB-120 commuter aircraft also experienced an inflight loss of
a portion of a propeller blade. This blade fractured at approximately
the 19-inch station and the remainder of the propeller blade,
propeller, and gearbox remained intact.
Subsequent metallurgical examination of these fractured blades
revealed that the fracture initiated in a small cavity or pit that
formed on the inner surface of the taper bore inside the aluminum blade
spar. Further laboratory investigations revealed these corrosion pits
may develop occasionally when chlorine residue present in the cork used
to seal the inner taper bore combines with water in the presence of
oxygen. That condition, if not corrected, could result in loss of a
propeller blade due to cracks initiating in the blade taper bore, that
can result in possible aircraft damage, and possible loss of aircraft
control.
Since the issuance of that AD, the FAA has conducted engineering
and laboratory investigation and analysis of world-wide inspection
results received from AD 94-09-06. This data indicates that either
periodic ultrasonic shear wave inspection of the propeller taper bore
should be conducted every 1,250 flight cycles in service (CIS) in order
to discover cracks that may initiate in pits, or a one-time visual and
borescope inspection of the taper bore should be conducted after
removing the propeller inner taper bore cork seal to insure that no
corrosion has occurred.
The FAA has reviewed and approved the technical contents of the
following Hamilton Standard Service Bulletins (SB's) and Alert Service
Bulletins (ASB's):
ASB's No. 14RF-9-61-A66, No. 14RF-19-61-A34, No. 14RF-21-61-A53,
No. 14SF-61-A73, and No. 6/5500/F-61-A27, all dated April 18, 1994,
that describe procedures for ultrasonic shear wave inspections of the
[[Page 12664]] blade taper bores for cracks. These ASB's are the same
as those referenced in AD 94-09-06.
SB's No. 14RF-9-61-70, dated August 26, 1994; No. 14RF-19-61-37,
dated August 29, 1994; No. 14RF-21-61-56, dated August 29, 1994; No.
14SF-61-75, dated August 29, 1994; and No. 6/5500/F-61-30, dated August
29, 1994. These SB's describe procedures to remove the propeller inner
taper bore cork seal and inspect the inside surface of the taper bore
for corrosion pits visually and by borescope. Blades found to be free
of pits are marked and reidentified. Propeller blade maintenance logs
shall also be annotated to show compliance with this AD. Blades found
to have any corrosion pits during these inspections shall be removed
from service prior to further flight and sent to an FAA-approved repair
facility for disposition in accordance with the instructions of the
appropriate SB.
ASB's No. 14SF-61-A74, Revision 1, dated October 5, 1994; No. 14RF-
9-61-A69, Revision 1, dated October 5, 1994; No. 14RF-19-61-A36,
Revision 1, dated October 5, 1994; No. 14RF-21-61-A55, Revision 1,
dated October 5, 1994; and No. 6/5500/F-61-A29, dated August 29, 1994.
These ASB's list the serial numbers of all blades with unpeened taper
bores by model that require inspection. These ASB's present several
options as to how to inspect the blade taper bores, and also give
instructions to operators and repair facilities on how to report
inspection data in order to show compliance with the AD.
Since an unsafe condition has been identified that is likely to
exist or develop on other propellers of this same type design, this AD
supersedes AD 94-09-06 to require initial and repetitive ultrasonic
shear wave inspections and a one-time visual and borescope inspection
of the taper bore for corrosion. Accomplishment of the visual and
borescope inspection constitutes terminating action to the repetitive
ultrasonic shear wave inspections. The actions are required to be
accomplished in accordance with the SB's and ASB's described
previously.
Since a situation exists that requires the immediate adoption of
this regulation, it is found that notice and opportunity for prior
public comment hereon are impracticable, and that good cause exists for
making this amendment effective in less than 30 days.
Comments Invited
Although this action is in the form of a final rule that involves
requirements affecting flight safety and, thus, was not preceded by
notice and an opportunity for public comment, comments are invited on
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All
communications received on or before the closing date for comments will
be considered, and this rule may be amended in light of the comments
received. Factual information that supports the commenter's ideas and
suggestions is extremely helpful in evaluating the effectiveness of the
AD action and determining whether additional rulemaking action would be
needed.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify the 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 that
summarizes each FAA-public contact concerned with the substance of this
AD 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 95-ANE-02.'' The postcard will be date stamped and
returned to the commenter.
The regulations adopted herein will 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 final
rule does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
The FAA has determined that this regulation is an emergency
regulation that must be issued immediately to correct an unsafe
condition in aircraft, and is not a ``significant regulatory action''
under Executive Order 12866. It has been determined further that this
action involves an emergency regulation under DOT Regulatory Policies
and Procedures (44 FR 11034, February 26, 1979). If it is determined
that this emergency regulation otherwise would be significant under DOT
Regulatory Policies and Procedures, a final regulatory evaluation will
be prepared and placed in the Rules Docket. A copy of it, if filed, may
be obtained from the Rules Docket at the location provided under the
caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends 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 removing Amendment 39-8894, (59 FR
19127, April 22, 1994), and by adding a new airworthiness directive,
Amendment 39-9170, to read as follows:
95-05-03 Hamilton Standard: Amendment 39-9170. Docket 95-ANE-02.
Supersedes AD 94-09-06, Amendment 39-8894.
Applicability: Hamilton Standard Models 14RF-9, 14RF-19, 14RF-
21, and 14SF-5, 14SF-7, 14SF-11, 14SFL11, 14SF-15, 14SF-17, 14SF-19,
and 14SF-23; and Hamilton Standard/British Aerospace 6/5500/F
propellers installed on but not limited to Embraer EMB-120 and EMB
120-RT; SAAB-SCANIA SF 340B; Aerospatiale ATR42-100, ATR42-300,
ATR42-320, ATR72; DeHavilland DHC-8-100 series, DHC-8-300 Series;
Construcciones Aeronauticas SA (CASA) CN-235 series and CN-235-100;
Canadair CL-215T and CL-415; and British Aerospace ATP airplanes.
Compliance: Required as indicated, unless accomplished
previously.
To prevent loss of a propeller blade due to cracks initiating in
the blade taper bore, that can result in possible aircraft damage,
and possible loss of aircraft control, accomplish the following:
(a) For propeller blades that have accumulated 1,750 or more
flight cycles since ultrasonic shear wave inspection in accordance
with AD 94-09-06, perform either paragraph (a) or (d) of this AD
within 100 flight cycles of the effective date of this AD:
(1) Perform an ultrasonic shear wave inspection for cracks in
the blade taper bore, in accordance with the procedures described in
the following Hamilton Standard Alert Service Bulletins (ASB's), as
applicable: No. 14RF-21-61-A53, dated April 18, 1994, and No. 14RF-
21-61-A55, Revision 1, dated October 5, 1994; No. 14SF-61-A73, dated
April 18, 1994, and No. 14SF-61-A74, [[Page 12665]] Revision 1,
dated October 5, 1994; No. 14RF-19-61-A34, dated April 18, 1994, and
No. 14RF-19-61-A36, Revision 1, dated October 5, 1994; No. 14RF-9-
61-A66, dated April 18, 1994, and No. 14RF-9-61-A69, Revision 1,
dated October 5, 1994; No. 6/5500/F-61-A27, dated April 18, 1994,
and No. 6/5500/F-61-A29, dated August 29, 1994. Remove cracked
propeller blades and replace with a serviceable blade prior to
further flight.
(2) Thereafter, perform repetitive ultrasonic shear wave
inspections at intervals not to exceed 1,250 CIS since last
inspection in accordance with the applicable Hamilton Standard ASB's
listed in paragraph (a)(1) of this airworthiness directive (AD).
Remove cracked propeller blades and replace with a serviceable blade
prior to further flight.
(3) No later than December 31, 1997, perform the visual and
borescope inspection required by paragraph (d) of this AD.
(b) For propeller blades that have accumulated less than 1,750
flight cycles since ultrasonic shear wave inspection in accordance
with AD 94-09-06, perform either paragraph (a) or (d) of this AD
before accumulating 1,850 flight cycles since ultrasonic shear wave
inspection in accordance with AD 94-09-06.
(c) For propeller blades that have not been inspected in
accordance with AD 94-09-06, perform paragraphs (a)(1) or (d) of
this AD prior to installing the blade in service and thereafter
perform paragraph (a)(2) of this AD if applicable.
(d) Prior to December 31, 1997, remove and scrap the propeller
inner taper bore cork seal and visually inspect the inside surface
of the taper bore for corrosion pits in accordance with the
applicable Hamilton Standard Service Bulletins (SB's): No. 14RF-9-
61-70, dated August 26, 1994; No. 14RF-19-61-37, dated August 29,
1994; No. 14RF-21-61-56, dated August 29, 1994; No. 14SF-61-75,
dated August 29, 1994; and No. 6/5500/F-61-30, dated August 29,
1994.
(1) For propeller blades found with any corrosion pits, remove
from service prior to further flight and send the propeller blades
to an FAA-approved repair facility for disposition in accordance
with Hamilton Standard ASB's No. 14SF-61-A74, Revision 1, dated
October 5, 1994; No. 14RF-9-61-A69, Revision 1, dated October 5,
1994; No. 14RF-19-61-A36, Revision 1, dated October 5, 1994; No.
14RF-21-61-A55, Revision 1, dated October 5, 1994; and No. 6/5500/F-
61-A29, dated August 29, 1994; as applicable.
(2) For propeller blades found with no corrosion pits, mark the
blade and return it to service in accordance with the Hamilton
Standard SB's listed in paragraph (d) of this AD.
(3) Returning propeller blades to service in accordance with
paragraph (d) of this AD constitutes terminating action to the
repetitive ultrasonic shear wave inspections required by paragraph
(a)(2) of this AD.
(e) For the purpose of this AD, a flight cycle is defined as one
takeoff and the next landing of an aircraft.
(f) 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, Boston Aircraft Certification
Office. The request should be forwarded through an appropriate FAA
Principal Maintenance Inspector, who may add comments and then send
it to the Manager, Boston Aircraft Certification Office.
Note: Information concerning the existence of approved
alternative methods of compliance with this airworthiness directive,
if any, may be obtained from the Boston Aircraft Certification
Office.
(g) 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 aircraft to a location where
the requirements of this AD can be accomplished.
(h) The requirements of this AD shall be done in accordance with
the following Hamilton Standard ASB's and SB's:
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Document No. Pages Revision Date
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ASB No. 14SF-61- 1-7 1............... October 5, 1994.
A74.
Total pages:
7.
ASB No. 14SF-61- 1-19 Original........ April 18, 1994.
A73.
Total pages:
19.
SB No. 14SF-61-75. 1-17 Original........ August 29, 1994.
Total pages:
17.
ASB No. 14RF-9-61- 1-6 1............... October 5, 1994.
A69.
Total pages:
6.
ASB No. 14RF-9-61- 1-19 Original........ April 18, 1994.
A66.
Total pages:
19.
SB No. 14RF-9-61- 1-17 Original........ August 29, 1994.
70.
Total pages:
17.
ASB No. 14RF-19-61- 1-6 1............... October 5, 1994.
A36.
Total pages:
6.
ASB No. 14RF-19-61- 1-19 Original........ April 18, 1994.
A34.
Total pages:
19.
SB No. 14RF-19-61- 1-17 Original........ August 29, 1994.
37.
Total pages:
17.
ASB No. 14RF-21-61- 1-6 1............... October 5, 1994.
A55.
Total pages:
6.
ASB No. 14RF-21-61- 1-19 Original........ April 18, 1994.
A53.
Total pages:
19.
SB No. 14RF-21-61- 1-17 Original........ August 29, 1994.
56.
Total pages:
17.
ASB No. 6/5500/F- 1-5 Original........ August 29, 1994.
61-A29.
Total pages:
5.
ASB No. 6/5500/F- 1-19 Original........ April 18, 1994.
61-A27.
Total pages:
19.
SB No. 6/5500/F-61- 1-17 Original........ August 29, 1994.
30.
Total pages:
17.
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The incorporation by reference of the following Hamilton
Standard ASB's was approved by the Director of the Federal Register
as of May 2, 1994: ASB's No. 14RF-9-61-A66, No. 14RF-19-61-A34, No.
14RF-21-61-A53, No. 14SF-61-A73, and No.P6/5500/F-61-A27, all dated
April 18, 1994. The incorporation by reference of all other Hamilton
Standard ASB's and SB's listed in this AD was approved by the
Director of the Federal Register in accordance with 5 U.S.C. 552(a)
and 1 CFR part 51. Copies may be obtained from Hamilton Standard,
One Hamilton Road, Windsor Locks, CT 06096-1010; telephone (203)
654-3610. Copies may be inspected at the FAA, New England Region,
Office of the Assistant Chief Counsel, 12 New England Executive
Park, Burlington, MA; or at the Office of the Federal Register, 800
North Capitol Street, NW., suite 700, Washington, DC.
(i) This amendment becomes effective on March 23, 1995.
[[Page 12666]] Issued in Burlington, Massachusetts, on February
28, 1995.
James C. Jones,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 95-5483 Filed 3-7-95; 8:45 am]
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