[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