[Federal Register Volume 60, Number 108 (Tuesday, June 6, 1995)]
[Proposed Rules]
[Pages 29797-29800]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-13785]
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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 95-ANE-32]
Airworthiness Directives; Hamilton Standard 14RF, 247F, 14SF, and
6/5500/F Series Propellers
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the supersedure of an existing
airworthiness directive (AD), applicable to Hamilton Standard 14RF,
247F, 14SF, and 6/5500/F (formerly Hamilton Standard/British Aerospace
6/5500/F) series propellers, that currently requires initial and
repetitive inspections of the propeller control unit (PCU) servo
ballscrew internal spline (BIS) teeth for wear, and replacement, if
necessary, of PCU servo BIS assemblies. This proposed AD would increase
the repetitive PCU servo BIS teeth inspection interval from 1,500 to
2,500 hours time in service (TIS) for propellers that have a ballscrew
quill damper installed. In addition, this proposed AD would add an
optional terminating action to the repetitive PCU servo BIS teeth
inspections by installing a Secondary Drive Quill (SDQ). If an SDQ is
installed, this proposed AD would require initial and repetitive torque
check inspections of the primary ballscrew quill. This proposal is
prompted by field service and laboratory test data that indicate that
the repetitive inspection interval can be safely increased, and by the
development and availability of the SDQ. The actions specified by the
proposed AD are intended to prevent inability to control the propeller
blade angle due to tooth wear in the PCU servo BIS assembly.
DATES: Comments must be received by July 6, 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-32, 12 New England
Executive Park, Burlington, MA 01803-5299. Comments may be inspected at
this location between 8:00 a.m. and 4:30 p.m., Monday through Friday,
except Federal holidays.
The service information referenced in the proposed rule may be
obtained from Hamilton Standard, One Hamilton Road, Windsor Locks, CT
06096-1010. This information may be examined at the FAA, New England
Region, Office of the Assistant Chief Counsel, 12 New England Executive
Park, Burlington, MA.
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:
Comments Invited
Interested persons are invited to participate in the making of the
[[Page 29798]] 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 notice 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 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-32.'' The postcard will be date stamped and
returned to the commenter.
Availability of NPRMs
Any person may obtain a copy of this NPRM by submitting a request
to the FAA, New England Region, Office of the Assistant Chief Counsel,
Attention: Rules Docket No. 95-ANE-32, 12 New England Executive Park,
Burlington, MA 01803-5299.
Discussion
On October 26, 1994, the Federal Aviation Administration (FAA)
issued AD 94-22-12, Amendment 39-9062 (59 FR 55199, November 4, 1994),
applicable to Hamilton Standard 14RF, 247F, 14SF, and 6/5500/F
(formerly Hamilton Standard/British Aerospace 6/5500/F) series
propellers, to increase the repetitive inspection interval from 500 to
1,500 hours time in service (TIS) since last inspection for propellers
that have a ballscrew quill damper installed. That action was prompted
by the availability of improved hardware that restricts quill motion
and enhances the lubrication of the BIS and significantly reduces BIS
wear. Severe wear of the BIS affects the ability to control the
propeller blade angle. That condition, if not corrected, could result
in inability to control the propeller blade angle due to tooth wear in
the PCU servo BIS assembly.
Since the issuance of that AD, the FAA has received field service
data and additional data accumulated on six controlled PCU's. These six
controlled PCU's show no BIS wear in more than 2,500 hours TIS for
PCU's with ballscrew quill dampers installed.
In addition, Hamilton Standard has developed redundant design
hardware that incorporates a secondary drive path for control between
the PCU and the propeller oil transfer tube. This redundant hardware is
known as the Secondary Drive Quill (SDQ) installation. The SDQ is
currently being installed on new production PCU's. For in-service
PCU's, this SDQ installation, accomplished by service bulletin at field
repair stations, is optional; however, this proposed AD makes
installation of the SDQ terminating action to the repetitive PCU servo
BIS teeth inspections. With the SDQ installed, this proposed AD would
require initial and repetitive torque check inspections of the primary
ballscrew quill.
The FAA has reviewed and approved the technical contents of the
following Hamilton Standard Alert Service Bulletins (ASB's), all dated
May 5, 1995: No. 14SF-61-A59, Revision 6; No. 14RF-9-61-A53, Revision
7; No. 14RF-19-61-A25, Revision 6; No. 14RF-21-61-A38, Revision 6; No.
247F-61-A3, Revision 5; and No. 6/5500/F-61-A11, Revision 6. These
ASB's enable affected propellers with a ballscrew quill damper
installed in production or in accordance with the following Hamilton
Standard Service Bulletins (SB's), all dated September 27, 1994, to
extend the repetitive PCU servo BIS teeth inspection interval from 500
to 2,500 hours TIS since last inspection: No. 14SF-61-67, Revision 2;
No. 14RF-9-61-61, Revision 1; No. 14RF-19-61-29, Revision 2; No. 14RF-
21-61-48, Revision 2; No. 247F-61-6, Revision 2; and No. 6/5500/F-61-
19, Revision 2.
In addition, the FAA has reviewed and approved the technical
contents of the following Hamilton Standard SB's, all Revision 1, all
dated May 17, 1995: No. 14SF-61-82; No. 14RF-9-61-76; No. 14RF-19-61-
43; No. 14RF-21-61-62; No. 247F-61-13; and No. 6/5500/F-61-33. These
SB's describe procedures for installing the SDQ.
Also, the FAA has reviewed and approved the technical contents of
the following Hamilton Standard SB's, all Revision 1, dated May 17,
1995; No. 14SF-61-81; No. 14RF-9-61-75; No. 14RF-19-61-41; No. 14RF-21-
61-60; No. 247F-61-12; and No. 6/5500/F-61-33. These SB's describe
procedures for initial and repetitive torque check inspections of the
primary ballscrew quill if the SDQ is installed.
Since an unsafe condition has been identified that is likely to
exist or develop on other products of this same type design, the
proposed AD would supersede AD 94-22-12 to increase the repetitive PCU
servo BIS teeth inspection interval from 1,500 to 2,500 TIS for
propellers that have a ballscrew quill damper installed. In addition,
this proposed AD would add an optional terminating action to the
repetitive PCU servo BIS teeth inspections by installing a SDQ. With
the SDQ installed, this proposed AD would require an initial torque
check inspection of the primary ballscrew quill at 5,000 hours TIS
since installation of the SDQ, and thereafter repetitive torque check
inspections at intervals not to exceed 5,000 hours TIS since last
inspection.
There are approximately 2,506 propellers of the affected design in
the worldwide fleet. The FAA estimates that 1,150 propellers installed
on aircraft of U.S. registry would be affected by this proposed AD,
that it would take approximately 1.5 work hours per propeller to
accomplish the PCU servo BIS teeth inspections, and that the average
labor rate is $60 per work hour. Based on these figures, and on the
average utilization rate of 2,000 hours TIS per year equating to 1.3
inspections per year, the total cost impact of the current AD per year
on U.S. operators is estimated to be $134,550. However, this proposed
superseding AD would require only 0.8 inspections per year, resulting
in an approximate yearly inspection cost of $82,800, which would
provide an approximate yearly savings to U.S. operators of $51,750.
The optional terminating action would require 4 work hours to
install the SDQ, and required parts would cost approximately $5,500 per
propeller. With the SDQ installed, the proposed AD would require
initial and repetitive torque check inspections of the primary
ballscrew quill. The torque check inspection would take 3 work hours to
perform the required actions, and with an average utilization rate of
2,000 hours TIS per year equating to 0.4 inspections per year,
resulting in an approximate yearly inspection cost of $72 per
propeller.
The regulations proposed herein would 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
proposal would not have sufficient federalism implications to warrant
the preparation of a Federalism Assessment. [[Page 29799]]
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. 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 39-9062 (59 FR
55199, November 4,1994) and by adding a new airworthiness directive to
read as follows:
Hamilton Standard: Docket No. 95-ANE-32. Supersedes AD 94-22-12,
Amendment 39-9062.
Applicability: Hamilton Standard Models 14RF-9, 14RF-19, 14RF-
21, and 14RF-23; 247F-1; 14SF-5, 14SF-7, 14SF-11, 14SFL11, 14SF-15,
14SF-17, 14SF-19, 14SF-23; and 6/5500/F propellers installed on but
not limited to Embraer EMB-120 and EMB-120RT; SAAB-SCANIA SF340B;
Aerospatiale ATR42-100, ATR42-300, ATR42-320, ATR72, ATR72-210;
DeHavilland DHC-8-100 series, DHC-8-300; Construcciones Aeronauticas
SA (CASA) CN-235 and CN-235-100; Canadair CL215T and CL415; and
British Aerospace ATP airplanes.
Note: This AD applies to each propeller identified in the
preceding applicability provision, regardless of whether it has been
modified, altered, or repaired in the area subject to the
requirements of this AD. For propellers that have been modified,
altered, or repaired so that the performance of the requirements of
this AD is affected, the owner/operator must use the authority
provided in paragraph (d) to request approval from the FAA. This
approval may address either no action, if the current configuration
eliminates the unsafe condition, or different actions necessary to
address the unsafe condition described in this AD. Such a request
should include an assessment of the effect of the changed
configuration on the unsafe condition addressed by this AD. In no
case does the presence of any modification, alteration, or repair
remove any propeller from the applicability of this AD.
Compliance: Required as indicated, unless accomplished
previously.
To prevent the inability to control the propeller blade angle
due to tooth wear in the propeller control unit (PCU) servo
ballscrew internal spline (BIS) assembly, accomplish the following:
(a) Inspect the PCU servo BIS assembly for tooth wear in
accordance with the Accomplishment Instructions of the following
Hamilton Standard Alert Service Bulletins (ASB), all dated May 5,
1995, as applicable: No. 14RF-9-61-A53, Revision 7; No. 14RF-19-61-
A25, Revision 6; No. 14RF-21-61-A38, Revision 6; No. 247F-61-A3,
Revision 5; No. 14SF-61-A59, Revision 6; and No. 6/5500/F-61-A11,
Revision 6; as follows:
(1) For a PCU with unknown time in service (TIS), and unknown
TIS since the last inspection, on the effective date of this
airworthiness directive (AD), and that does not have a ballscrew
quill damper installed, inspect within 200 hours TIS after the
effective date of this AD.
(2) For a PCU with 1,800 or more hours TIS or unknown TIS on the
effective date of this AD, and either has not been inspected, or has
been inspected more than 500 hours prior to the effective date of
this AD, in accordance with the applicable Hamilton Standard ASB
listed in paragraph (a) of this AD; and that does not have a
ballscrew quill damper installed; inspect within 200 hours TIS after
the effective date of this AD.
(3) For a PCU with 1,800 or more hours TIS or unknown TIS on the
effective date of this AD, and that has been inspected within the
previous 500 hours TIS in accordance with the applicable Hamilton
Standard ASB listed in paragraph (a) of this AD, and that does not
have a ballscrew quill damper installed, inspect within 500 hours
TIS since the last inspection in accordance with the applicable
Hamilton Standard ASB listed in paragraph (a) of this AD.
(4) For a PCU with less than 1,800 hours TIS on the effective
date of this AD, and that does not have a ballscrew quill damper
installed, inspect prior to accumulating 1,800 hours TIS, or within
300 hours TIS after the effective date of this AD, whichever occurs
later.
(5) For a PCU that has a ballscrew quill damper installed in
production or in accordance with the following applicable Hamilton
Standard Service Bulletins (SB), all dated September 27, 1994, or
previous revisions: No. 14SF-61-67, Revision 2; No. 14RF-9-61-61,
Revision 1; No. 14RF-19-61-29, Revision 2; No. 14RF-21-61-48,
Revision 2; No. 247F-61-6, Revision 2; and No. 6/5500/F-61-19,
Revision 2; inspect within 2,500 hours TIS since installation of the
ballscrew quill damper
(6) Thereafter, inspect at intervals described as follows:
(i) For propellers that have a ballscrew quill damper installed
in production or in accordance with the applicable Hamilton Standard
SB listed in paragraph (a)(5) of this AD, or previous revisions,
inspect at intervals not to exceed 2,500 hours TIS since the last
inspection required by this AD.
(ii) For propellers that do not have a ballscrew quill damper
installed in production or in accordance with the applicable
Hamilton Standard SB listed in paragraph (a)(5) of this AD, inspect
at intervals not to exceed 500 hours TIS since the last inspection
required by this AD.
(7) If PCU servo BIS teeth are worn beyond the limits specified
in the Accomplishment Instructions of the applicable ASB's listed in
paragraph (a) of this AD, prior to further flight, replace the PCU
with a serviceable assembly in accordance with the Accomplishment
Instructions of the applicable ASB's listed in paragraph (a) of this
AD, and thereafter reinspect in accordance with paragraphs (a)(6)
and (a)(7) of this AD.
(b) Operators have the option of installing a Secondary Drive
Quill (SDQ) in accordance with the Accomplishment Instructions of
the following applicable Hamilton Standard SB's, all Revision 1, all
dated May 17, 1995: No. 14SF-61-82; No. 14RF-9-61-76; No. 14RF-19-
61-43; No. 14RF-21-61-62; No. 247F-61-13; and No. 6/5500/F-61-33.
Installation of an SDQ constitutes terminating action to the
repetitive inspections required by paragraph (a) of this AD.
(c) With an SDQ installed, perform an initial torque check
inspection of the primary ballscrew quill at 5,000 hours TIS since
installation of the SDQ, and thereafter at intervals not to exceed
5,000 hours TIS since last inspection, and remove from service and
replace with a serviceable part, if necessary, in accordance with
the following applicable Hamilton Standard SB's, all Revision 1,
dated May 17, 1995: No. 14SF-61-81; No. 14RF-9-61-75; No. 14RF-19-
61-41; No. 14RF-21-61-60; No. 247F-61-12; and No. 6/5500/F-61-33.
(d) 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.
(e) 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.
[[Page 29800]] Issued in Burlington, Massachusetts, on May 30,
1995.
James C. Jones,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 95-13785 Filed 6-5-95; 8:45 am]
BILLING CODE 4910-13-U