AD 2010-17-11R2
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Dowty Propellers | (c)R408/6-123-F/17 | Airworthiness Directives; Dowty Propellers Constant Speed Propellers |
| propeller | Dowty Propellers | (c)R408/6-123-F/17 | Airworthiness Directives; Dowty Propellers Constant Speed Propellers |
Unsafe Condition
Failure of the propeller de-ice bus bar due to friction or contact between the bus bar and the backplate assembly, consequent intermittent short circuit, and possible double generator failure.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Initial application of sealant between the bus bar assembly and the backplate assembly for LRUs with S/N below DAP0347, repetitive re-application of sealant for all R408/6-123-F/17 propellers with S/N below DAP0927, and allow use of an additional specified sealant. Optional terminating action via Dowty SB D8400-61-94 revisions up to December 12, 2013.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
before further flight
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Dowty Propellers R408/6-123-F/17 model propellers with hub, actuator, and backplate assembly LRU serial numbers below DAP0927.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Propeller de-ice bus bar
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - 2010-17-11R2.pdf
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DetailsAttachments/Public Comments
AD Number:
2010-17-11R2
Document Type:
AD Final Rules
Docket Number:
FAA-2009-0776
Subject Heading:
Airworthiness Directives; Dowty Propellers Constant Speed Propellers
Subject:
Propeller de-ice bus bar
Status:
Current
Citation:
Federal Register Volume 79, Number 231 (Tuesday, December 2, 2014)
Citation Publish Date:
12/02/2014
Effective Date:
01/06/2015
Make:
Dowty Propellers
Model:
(c)R408/6-123-F/17
Product Type:
Propeller
Product Subtype:
Affected AD:
Superseded AD:
2010-17-11R1
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39
Comments:
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[Federal Register Volume 79, Number 231 (Tuesday, December 2, 2014)]
[Rules and Regulations]
[Pages 71300-71302]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-28325]
––––––––––––––––––––––––––––––––––
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2009-0776; Directorate Identifier 2009-NE-32-AD; Amendment 39-18007;
AD 2010-17-11R2]
RIN 2120-AA64
Airworthiness Directives; Dowty Propellers Constant Speed Propellers
AGENCY:
Federal Aviation Administration (FAA), DOT.
ACTION:
Final rule.
––––––––––––––––––––––––––––––––––
SUMMARY:
We are revising airworthiness directive (AD) 2010-17-11R1, which applies to all
Dowty Propellers R408/6-123-F/17 model propellers. AD 2010-17-11R1 required initial application
of sealant between the bus bar assembly and the backplate assembly of certain line-replaceable units
(LRUs) and repetitive re-applications of sealant on all R408/6-123-F/17 model propellers. AD 2010-
17-11R1 also provided an optional terminating action to the repetitive re-application of sealant. This
AD increases the interval allowed between the required re-application of sealant, and specifies an
additional acceptable sealant. This AD was prompted by failure of the propeller de-ice bus bar due to
friction or contact between the bus bar and the backplate assembly, consequent intermittent short
circuit, and possible double generator failure. We are issuing this AD to prevent an in-flight double
generator failure, which could result in reduced control of the airplane.
DATES:
This AD is effective January 6, 2015.
The Director of the Federal Register approved the incorporation by reference of certain
publications listed in this AD as of January 6, 2015.
ADDRESSES:
For service information identified in this AD, contact Dowty Propellers, Anson
Business Park, Cheltenham Road East, Gloucester GL2 9QN, UK; phone: 44 0 1452 716000; fax: 44
0 1452 716001. You may view this service information at the FAA, Engine & Propeller Directorate,
12 New England Executive Park, Burlington, MA. For information on the availability of this material
at the FAA, call 781-238-7125.
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-2009-0776; or in person at the Docket Management Facility between 9
2
a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD,
the mandatory continuing airworthiness information, regulatory evaluation, any comments received,
and other information. The address for the Docket Office (phone: 800-647-5527) is Document
Management Facility, 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:
Michael Schwetz, Aerospace Engineer, Boston
Aircraft Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park,
Burlington, MA 01803; phone: 781-238-7761; fax 781-238-7170; email: michael.schwetz@faa.gov.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to revise AD
2010-17-11R1, Amendment 39-17481 (78 FR 41283, July 10, 2013), (''AD 2010-17-11R1''). AD
2010-17-11R1 applied to the specified products. The NPRM published in the Federal Register on
March 19, 2014 (79 FR 15269). The NPRM proposed to require increasing the interval allowed
between the required re-application of sealant and specified an additional acceptable sealant.
Comments
We gave the public the opportunity to participate in developing this AD. We considered the
comments received.
Request Correction to the Applicability and Compliance Paragraphs
Horizon Air requested a correction in the Applicability and Compliance paragraphs for possible
typographical errors between AD 2010-17-11R1 and the NPRM (79 FR 15269, March 19, 2014).
Horizon Air stated that the Applicability has changed from ''. . . serial number (S/N) below
DAP0327'' in AD 2010-17-11R1 to ''. . . S/N below DAP0927'' in the proposed rule. With no
discussion about the increased number of affected propellers, Horizon Air believes that typographical
errors exist in the Applicability and Compliance sections.
We do not agree. AD 2010-17-11R1 required initial sealant application to all Dowty Propellers
R408/6-123-F/17 model propellers with a hub, actuator, and backplate assembly LRU S/Ns below
DAP0347, not DAP0327 as quoted above. AD 2010-17-11R1 also required repetitive re-application
of sealant for all LRU S/Ns below DAP0927. We did not change this AD.
Request Change to Optional Terminating Action
Horizon Air requested that all revisions to Dowty Propellers Service Bulletin (SB) No. D8400-
61-94 be included in the Optional Terminating Action paragraph. The implied reason for this request
was to support terminating action throughout the range of qualified SBs.
We partially agree. We agree that Dowty Propellers SB No. D8400-61-94, Revision 6, dated
December 12, 2013 and earlier revisions provide adequate corrective actions to address the unsafe
condition. We changed the Optional Terminating Action paragraph to include Dowty Propellers SB
No. D8400-61-94, Revision 6, dated December 12, 2013 and earlier revisions.
We do not agree that unknown future SB versions should be included in this AD. The content of
future SB revisions is speculation. We did not change this AD to include all revisions of the SB.
Document Text
Show stored source text (verify against official source)
AD Final Rules - 2010-17-11R2.pdf
Copy URL
Document Versions
Feedback
DetailsAttachments/Public Comments
AD Number:
2010-17-11R2
Document Type:
AD Final Rules
Docket Number:
FAA-2009-0776
Subject Heading:
Airworthiness Directives; Dowty Propellers Constant Speed Propellers
Subject:
Propeller de-ice bus bar
Status:
Current
Citation:
Federal Register Volume 79, Number 231 (Tuesday, December 2, 2014)
Citation Publish Date:
12/02/2014
Effective Date:
01/06/2015
Make:
Dowty Propellers
Model:
(c)R408/6-123-F/17
Product Type:
Propeller
Product Subtype:
Affected AD:
Superseded AD:
2010-17-11R1
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39
Comments:
Automatic Zoom
Actual Size
Page Fit
Page Width
50%
75%
100%
125%
150%
200%
300%
400%
125%
of 7
1
[Federal Register Volume 79, Number 231 (Tuesday, December 2, 2014)]
[Rules and Regulations]
[Pages 71300-71302]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-28325]
––––––––––––––––––––––––––––––––––
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2009-0776; Directorate Identifier 2009-NE-32-AD; Amendment 39-18007;
AD 2010-17-11R2]
RIN 2120-AA64
Airworthiness Directives; Dowty Propellers Constant Speed Propellers
AGENCY:
Federal Aviation Administration (FAA), DOT.
ACTION:
Final rule.
––––––––––––––––––––––––––––––––––
SUMMARY:
We are revising airworthiness directive (AD) 2010-17-11R1, which applies to all
Dowty Propellers R408/6-123-F/17 model propellers. AD 2010-17-11R1 required initial application
of sealant between the bus bar assembly and the backplate assembly of certain line-replaceable units
(LRUs) and repetitive re-applications of sealant on all R408/6-123-F/17 model propellers. AD 2010-
17-11R1 also provided an optional terminating action to the repetitive re-application of sealant. This
AD increases the interval allowed between the required re-application of sealant, and specifies an
additional acceptable sealant. This AD was prompted by failure of the propeller de-ice bus bar due to
friction or contact between the bus bar and the backplate assembly, consequent intermittent short
circuit, and possible double generator failure. We are issuing this AD to prevent an in-flight double
generator failure, which could result in reduced control of the airplane.
DATES:
This AD is effective January 6, 2015.
The Director of the Federal Register approved the incorporation by reference of certain
publications listed in this AD as of January 6, 2015.
ADDRESSES:
For service information identified in this AD, contact Dowty Propellers, Anson
Business Park, Cheltenham Road East, Gloucester GL2 9QN, UK; phone: 44 0 1452 716000; fax: 44
0 1452 716001. You may view this service information at the FAA, Engine & Propeller Directorate,
12 New England Executive Park, Burlington, MA. For information on the availability of this material
at the FAA, call 781-238-7125.
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-2009-0776; or in person at the Docket Management Facility between 9
2
a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD,
the mandatory continuing airworthiness information, regulatory evaluation, any comments received,
and other information. The address for the Docket Office (phone: 800-647-5527) is Document
Management Facility, 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:
Michael Schwetz, Aerospace Engineer, Boston
Aircraft Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park,
Burlington, MA 01803; phone: 781-238-7761; fax 781-238-7170; email: michael.schwetz@faa.gov.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to revise AD
2010-17-11R1, Amendment 39-17481 (78 FR 41283, July 10, 2013), (''AD 2010-17-11R1''). AD
2010-17-11R1 applied to the specified products. The NPRM published in the Federal Register on
March 19, 2014 (79 FR 15269). The NPRM proposed to require increasing the interval allowed
between the required re-application of sealant and specified an additional acceptable sealant.
Comments
We gave the public the opportunity to participate in developing this AD. We considered the
comments received.
Request Correction to the Applicability and Compliance Paragraphs
Horizon Air requested a correction in the Applicability and Compliance paragraphs for possible
typographical errors between AD 2010-17-11R1 and the NPRM (79 FR 15269, March 19, 2014).
Horizon Air stated that the Applicability has changed from ''. . . serial number (S/N) below
DAP0327'' in AD 2010-17-11R1 to ''. . . S/N below DAP0927'' in the proposed rule. With no
discussion about the increased number of affected propellers, Horizon Air believes that typographical
errors exist in the Applicability and Compliance sections.
We do not agree. AD 2010-17-11R1 required initial sealant application to all Dowty Propellers
R408/6-123-F/17 model propellers with a hub, actuator, and backplate assembly LRU S/Ns below
DAP0347, not DAP0327 as quoted above. AD 2010-17-11R1 also required repetitive re-application
of sealant for all LRU S/Ns below DAP0927. We did not change this AD.
Request Change to Optional Terminating Action
Horizon Air requested that all revisions to Dowty Propellers Service Bulletin (SB) No. D8400-
61-94 be included in the Optional Terminating Action paragraph. The implied reason for this request
was to support terminating action throughout the range of qualified SBs.
We partially agree. We agree that Dowty Propellers SB No. D8400-61-94, Revision 6, dated
December 12, 2013 and earlier revisions provide adequate corrective actions to address the unsafe
condition. We changed the Optional Terminating Action paragraph to include Dowty Propellers SB
No. D8400-61-94, Revision 6, dated December 12, 2013 and earlier revisions.
We do not agree that unknown future SB versions should be included in this AD. The content of
future SB revisions is speculation. We did not change this AD to include all revisions of the SB.
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.
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Unsafe Condition: Loss of the bonded metallic leading edge (L/E) guard of the propeller, which could result in damage to the propeller or to the airplane, or injury to personnel.
