AD 2004-13-01
Unsafe Condition
Propeller hub failure due to cracks in the hub, which could result in loss of control of the airplane.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Initial and repetitive ultrasonic inspections of propeller hubs, part number 660709201, installed on airplanes. For hubs and propellers in storage, initial ultrasonic inspection of propeller hubs before placing in service.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 50 flight hours or 6 months after the issue date of the relevant Mandatory Service Bulletin, whichever occurs first.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Dowty Aerospace Propellers Type R321/4-82-F/8, R324/4-82-F/9, R333/4-82-F/12, and R334/4-82-F/13 propeller assemblies with propeller hubs part number 660709201, installed on various aircraft models including CASA 212, British Aerospace Regional Aircraft Jetstream Models 3101 and 3201, Fairchild Aircraft Merlin IIIC, and Merlin IVC/Metro III airplanes.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
This amendment supersedes an existing airworthiness directive (AD) that applies to Dowty Aerospace Propellers (Dowty) Type R334/4-82- F/13 propeller assemblies. That AD currently requires a one-time ultrasonic inspection of propeller hubs, part number (P/N) 660709201, for cracks. This amendment requires initial and repetitive ultrasonic inspections of propeller hubs, P/N 660709201, that are installed on airplanes, and for hubs and propellers in storage, initial ultrasonic inspection of propeller hubs before placing in service. Propeller hubs, P/N 660709201, are installed on Type R321/4-82-F/8, R324/4-82-F/9, R333/4-82-F/12, and R334/4-82-F/13 propeller assemblies. This amendment results from the manufacturer's reevaluation of potential hub failure on Type R321/4-82-F/8, R324/4-82-F/9, R333/4-82-F/12, and R334/4-82-F/ 13 propeller assemblies. We are issuing this AD to prevent propeller hub failure due to cracks in the hub, which could result in loss of control of the airplane.
Document Text
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[Federal Register Volume 69, Number 119 (Tuesday, June 22, 2004)]
[Rules and Regulations]
[Pages 34560-34563]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 04-13773]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2001-NE-50-AD; Amendment 39-13681; AD 2004-13-01]
RIN 2120-AA64
Airworthiness Directives; Dowty Aerospace Propellers Type R321/4-
82-F/8, R324/4-82-F/9, R333/4-82-F/12, and R334/4-82-F/13 Propeller
Assemblies
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment supersedes an existing airworthiness directive
(AD) that applies to Dowty Aerospace Propellers (Dowty) Type R334/4-82-
F/13 propeller assemblies. That AD currently requires a one-time
ultrasonic inspection of propeller hubs, part number (P/N) 660709201,
for cracks. This amendment requires initial and repetitive ultrasonic
inspections of propeller hubs, P/N 660709201, that are installed on
airplanes, and for hubs and propellers in storage, initial ultrasonic
inspection of propeller hubs before placing in service. Propeller hubs,
P/N 660709201, are installed on Type R321/4-82-F/8, R324/4-82-F/9,
R333/4-82-F/12, and R334/4-82-F/13 propeller assemblies. This amendment
results from the manufacturer's reevaluation of potential hub failure
on Type R321/4-82-F/8, R324/4-82-F/9, R333/4-82-F/12, and R334/4-82-F/
13 propeller assemblies. We are issuing this AD to prevent propeller
hub failure due to cracks in the hub, which could result in loss of
control of the airplane.
DATES: Effective July 27, 2004. The incorporation by reference of
certain publications listed in the regulations is approved by the
Director of the Federal Register as of July 27, 2004.
ADDRESSES: The service information referenced in this AD may be
obtained from Dowty Aerospace Propellers, Anson Business Park,
Cheltenham Road East, Gloucester GL 29QN, UK; telephone 44 (0) 1452
716000; fax 44 (0) 1452 716001. This information may be examined, by
appointment, at the Federal Aviation Administration (FAA), New England
Region, Office of the Regional Counsel, 12 New England Executive Park,
Burlington, MA; or at the National Archives and Records Administration
(NARA). For information on the availability of this material at NARA,
call 202-741-6030, or go to: <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
FOR FURTHER INFORMATION CONTACT: Frank Walsh, Aerospace Engineer,
Boston Aircraft Certification Office, FAA, Engine and Propeller
Directorate, telephone (781) 238-7158, fax (781) 238-7170.
SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal
Aviation Regulations (14 CFR part 39) by superseding AD 2002-01-28,
Amendment 39-12623 (67 FR 4351, January 30, 2002), that applies to
Dowty Type R334/4-82-F/13 propeller assemblies was published in the
Federal Register on April 28, 2003 (68 FR 22339). That action proposed
to require initial and repetitive ultrasonic inspections of propeller
hubs, P/N 660709201, that are installed on airplanes, and for hubs and
propellers in storage, initial ultrasonic inspection of propeller hubs
before placing in service. That action proposed to perform
[[Page 34561]]
inspections in accordance with Dowty Mandatory Service Bulletin (MSB)
No. 61-1119, Revision 3, dated March 8, 2002; MSB No. 61-1124, Revision
1, dated October 8, 2002; MSB No. 61-1125, Revision 1, dated October 9,
2002; and MSB No. 61-1126, Revision 1, dated October 9, 2002. The Civil
Aviation Authority (CAA), which is the airworthiness authority for the
United Kingdom (UK), classified these service bulletins as mandatory
and issued CAA UK AD No. 003-11-2001, dated November 30, 2001; CAA UK
AD No. 009-05-2002, dated April 15, 2003; CAA UK AD No. 010-05-2002,
dated April 15, 2003; and CAA UK AD No. 011-05-2002, dated April 15,
2003 in order to ensure the airworthiness of these Dowty Propellers in
the UK.
Comments
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
Request To Increase the Initial Inspection Interval
One commenter states that the initial inspection interval in the
NPRM of 50 hours is unrealistically short to complete the inspection on
a large, geographically wide-spread fleet. The commenter believes that
the initial inspection interval should be increased to 200 hours.
We do not agree that we need to change the compliance time for the
initial inspection. Dowty issued an MSB on May 7, 2002, and directed
operators to conduct the initial inspection. Dowty also stated that the
calendar compliance time for that inspection was within six months
after the issue date of that MSB. Based on the issuance date of that
MSB, all propellers should already be inspected. We have not changed
the AD.
Request To Increase the Repetitive Inspection Interval
One commenter requests that the repetitive inspection interval in
the NPRM be increased from 1,000 hours to 2,000 hours based on the fact
that only one crack was found in their fleet.
We do not agree. Dowty based the compliance time on an engineering
evaluation of the 16 cracks found by this inspection. Five cracks were
found on the same propeller model as flown by the commenter. We have
not changed the AD.
Credit for Previous Inspections on All Models
One commenter states that the previous inspections on the propeller
should be applicable to all models, not just the R334/4-82-F13
propeller.
We agree. We have changed the Applicability in the Regulatory text
of the AD by adding Dowty Propeller Types R321/4-82-F/8, R324/4-82-F/9,
and R333/4-82-F/12.
Request To Clarify the Economic Analysis Paragraph
One commenter states that the FAA underestimated the cost of the AD
to U.S. operators. The commenter also provides additional information
to better estimate the cost of the inspection.
We agree. Our revised estimate retains the 11 work hours per
propeller and modifies the part cost from $1,650 per propeller to $300
per propeller. In addition, we increased the estimated number of
airplanes from 10 airplanes to 50 airplanes and raised the labor rate
to $65 per hour. Based on these revisions, the total cost for the
inspection for U.S. operators will be about $126,875 for the fleet of
affected airplanes.
Clarification of CAA ADs Related to This AD
We inadvertently left out three CAA UK ADs in Note 3 of the NRPM
supersedure. We have added the three CAA UK ADs in Note 3 of the AD.
After careful review of the available data, including the comments
noted above, the FAA has determined that air safety and the public
interest require the adoption of the rule with the changes described
previously. The FAA has determined that these changes will neither
increase the economic burden on any operator nor increase the scope of
the AD.
Bilateral Agreement Information
These propeller models are manufactured in the UK and are Type
certificated for operation in the United States under the provisions of
Section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and
the applicable bilateral airworthiness agreement. Pursuant to this
bilateral airworthiness agreement, the CAA has kept the FAA informed of
the situation described above. The FAA has examined the findings of the
CAA, reviewed all available information, and determined that AD action
is necessary for products of this type design that are certificated for
operation in the United States.
Economic Analysis
There are about 275 airplanes with propellers of the affected
design in the worldwide fleet. The FAA estimates that there are about
125 Dowty Propellers Type R321/4-82-F/8, R324/4-82-F/9, R333/4-82-F/12,
and R334/4-82-F/13 installed on airplanes of U.S. registry that would
be affected by this AD. The FAA also estimates that it would take
approximately 11 work hours per propeller to perform one inspection and
replacement, and that the average labor rate is $65 per work hour.
Required shipping and parts would cost approximately $300 per
propeller. Based on these figures, the total cost of the AD to known
U.S. operators is estimated to be $126,875.
Regulatory Analysis
This final rule does not have federalism implications, as defined
in Executive Order 13132, because it would 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. Accordingly,
the FAA has not consulted with state authorities prior to publication
of this final rule.
For the reasons discussed above, I certify that this action (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) 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 final evaluation has been prepared for this action
and it 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, Incorporation by
reference, Safety.
Adoption of the Amendment
0
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
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. Section 39.13 is amended by removing Amendment 39-12623 (67 FR
[[Page 34562]]
4351, January 30, 2002) and by adding a new airworthiness directive,
Amendment 39-13681, to read as follows:
2004-13-01 Dowty Aerospace Propellers: Amendment 39-13681. Docket
No. 2001-NE-50-AD. Supersedes AD 2002-01-28, Amendment 39-12623.
Applicability
This airworthiness directive (AD) applies to Dowty Aerospace
Propellers (Dowty) Type R321/4-82-F/8, R324/4-82-F/9, R333/4-82-F/
12, and R334/4-82-F/13 propeller assemblies with propeller hubs part
number (P/N) 660709201. These propeller assemblies are installed on,
but not limited to, Construcciones Aeronauticas, S.A. (CASA) 212,
British Aerospace Regional Aircraft Jetstream Models 3101 and 3201,
Fairchild Aircraft, Inc., Merlin IIIC, and Merlin IVC/Metro III
airplanes.
Note 1: 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 request approval for an
alternative method of compliance in accordance with paragraph (f) of
this AD. The request should include an assessment of the effect of
the modification, alteration, or repair on the unsafe condition
addressed by this AD; and, if the unsafe condition has not been
eliminated, the request should include specific proposed actions to
address it.
Compliance
Compliance with this AD is required as indicated, unless already
done.
To prevent propeller hub failure due to cracks in the hub, which
could result in loss of control of the airplane, do the following:
Initial Ultrasonic Inspection
(a) Within 50 flight hours time-in-service (TIS) after the
effective date of this AD, or within 60 days after the effective
date of this AD, whichever occurs earlier, perform an initial
ultrasonic inspection of the rear wall of the rear half of the
propeller hub for cracks in accordance with Appendix A of the
applicable Dowty Mandatory Service Bulletin (MSB) listed in the
following Table 1:
Table 1.--Applicable MSB for Propeller Type
------------------------------------------------------------------------
Propeller assembly type Applicable MSB
------------------------------------------------------------------------
(1) R334/4-82-F/13..................... MSB No. 61-1119, Revision 3,
dated March 8, 2002.
(2) R333/4-82-F/12..................... MSB No. 61-1124, Revision 1,
dated October 8, 2002.
(3) R321/4-82-F/8...................... MSB No. 61-1125, Revision 1,
dated October 9, 2002.
(4) R324/4-82-F/9...................... MSB No. 61-1126, Revision 1,
dated October 9, 2002
------------------------------------------------------------------------
(b) For hubs and propellers in storage, perform an initial
ultrasonic inspection of the rear wall of the rear half of the
propeller hub for cracks, before placing in service, in accordance
with Appendix A of the applicable Dowty MSB listed in Table 1 of
this AD.
(c) Propeller hubs, P/N 660709201, used on Type R334/4-82-F/13
propeller assemblies that have been previously inspected using a
Dowty MSB listed in Table 1 or earlier issue of those MSBs, are
considered to be in compliance with paragraph (a) of this AD.
Repetitive Ultrasonic Inspections
(d) Thereafter, within 1,000 flight hours TIS after each
ultrasonic inspection, perform an ultrasonic inspection of the rear
wall of the rear half of the propeller hub for cracks in accordance
with Appendix A of the applicable Dowty MSB listed in Table 1 of
this AD.
Inspection Reporting Requirements
(e) For each inspection, record the inspection data on a copy of
Appendix B of the applicable MSB listed in Table 1 of this AD, and
report the findings to the Manager, Boston Aircraft Certification
Office, FAA, Engine and Propeller Directorate, 12 New England
Executive Park, Burlington, MA 01803-5299 within 10 days after the
inspection. Reporting requirements have been approved by the Office
of Management and Budget (OMB) and assigned OMB control number 2120-
0056.
Alternative Methods of Compliance
(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. Operators must submit their request through an appropriate
FAA principal Maintenance Inspector, who may add comments and then
send it to the Manager, Boston Aircraft Certification Office.
Note 2: 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.
Special Flight Permits
(g) Special flight permits may be issued in accordance with
Sec. Sec. 21.197 and 21.199 of the Federal Aviation Regulations (14
CFR 21.197 and 21.199) to operate the airplane to a location where
the requirements of this AD can be done.
Documents That Have Been Incorporated by Reference
(h) The inspections must be done in accordance with the
following Dowty Aerospace Propellers mandatory service bulletins:
----------------------------------------------------------------------------------------------------------------
Document No. Pages Revision Date
----------------------------------------------------------------------------------------------------------------
MSB No. 61-1119...................... 1..................... 3.................... Mar. 8, 2002.
2..................... 2.................... Dec. 6, 2001.
Appendix A........................... 1..................... 1.................... Nov. 27, 2001.
2..................... Original............. Nov. 1, 2001.
3-6................... 1.................... Nov. 27, 2001.
Appendix B........................... 1..................... Original............. Nov. 1, 2001.
Appendix C........................... All................... Original............. Nov. 27, 2001.
Appendix D........................... All................... Original............. Dec. 6, 2001.
Total pages: 29..................
--------------------------------------
MSB No. 61-1124...................... 1..................... 1.................... Oct. 8, 2002.
2-3................... Original............. May 7, 2002.
Appendix A........................... All................... Original............. May 7, 2002.
Appendix B........................... All................... Original............. May 7, 2002.
Appendix C........................... All................... Original............. May 7, 2002.
Appendix D........................... All................... Original............. May 7, 2002.
Total pages: 30..................
MSB No. 61-1125...................... 1..................... 1.................... Oct. 9, 2002.
2-3................... Original............. May 7, 2002.
Appendix A........................... All................... Original............. May 7, 2002.
Appendix B........................... All................... Original............. May 7, 2002.
Appendix C........................... All................... Original............. May 7, 2002.
Appendix D........................... All................... Original............. May 7, 2002.
Total pages: 30..................
MSB No. 61-1126...................... 1..................... 1.................... Oct. 9, 2002.
2-3................... Original............. May 7, 2002.
[[Page 34563]]
Appendix A........................... All................... Original............. May 7, 2002.
Appendix B........................... All................... Original............. May 7, 2002.
Appendix C........................... All................... Original............. May 7, 2002.
Appendix D........................... All................... Original............. May 7, 2002.
Total pages: 30..................
----------------------------------------------------------------------------------------------------------------
This incorporation by reference 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 Dowty Propellers, Anson
Business Park, Cheltenham Road East, Gloucester GL 29QN, UK;
telephone 44 (0) 1452 716000; fax 44 (0) 1452 716001. Copies may be
inspected at the FAA, New England Region, Office of the Regional
Counsel, 12 New England Executive Park, Burlington, MA; or at the
National Archives and Records Administration (NARA). For information
on the availability of this material at NARA, call 202-741-6030, or
go to: <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
Note 3: The subject of this AD is also addressed in CAA UK AD
No. 003-11-2001, dated November 30, 2001; CAA UK AD No. 009-05-2002,
dated April 15, 2003; CAA UK AD No. 010-05-2002, dated April 15,
2003; and CAA UK AD No. 011-05-2002, dated April 15, 2003.
Effective Date
(i) This amendment becomes effective on July 27, 2004.
Issued in Burlington, Massachusetts, on June 10, 2004.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 04-13773 Filed 6-21-04; 8:45 am]
BILLING CODE 4910-13-P
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Retrieved: Apr 4, 2026
Rights: U.S. Government Public Domain
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