AD Amdt-39-11284

Recurring final rule

Airworthiness Directives; Dowty Aerospace Propellers Model R381/ 6-123-F/5 Propellers

AD Number
Amdt-39-11284
Status
final_rule
Effective Date
Product Category
propeller
Docket
Docket No. 99-NE-43-AD
FR Citation
64 FR 47661
Technical illustration of an aircraft propeller assembly
Problem area Propeller

Unsafe Condition

Reports of a cracked composite propeller blade indicate potential for cracks across the camber face, leading to propeller blade separation and possible aircraft loss of control.

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Required Actions

Inspect propeller blades visually and using ultrasonic (UT) methods for cracks across the camber face. Replace any cracked blades with serviceable blades.

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Compliance Time

Within 50 flight hours after the effective date of this AD.

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Affected Aircraft

Dowty Aerospace Propellers Model R381/6-123-F/5 propellers.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment adopts a new airworthiness directive (AD) that is applicable to Dowty Aerospace Propellers Model R381/6-123-F/5 propellers. This action requires initial and repetitive visual and ultrasonic (UT) inspections of propeller blades for cracks across the camber face, and, if blades are found cracked, replacement with serviceable blades. This amendment is prompted by reports of a cracked composite propeller blade. The actions specified in this AD are intended to prevent propeller blade cracks and propagation, which could result in propeller blade separation and possible aircraft loss of control.

Document Text

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[Federal Register Volume 64, Number 169 (Wednesday, September 1, 1999)]
[Rules and Regulations]
[Pages 47661-47663]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 99-22563]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NE-43-AD; Amendment 39-11284; AD 99-18-18]
RIN 2120-AA64


Airworthiness Directives; Dowty Aerospace Propellers Model R381/
6-123-F/5 Propellers

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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[[Page 47662]]

SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
is applicable to Dowty Aerospace Propellers Model R381/6-123-F/5 
propellers. This action requires initial and repetitive visual and 
ultrasonic (UT) inspections of propeller blades for cracks across the 
camber face, and, if blades are found cracked, replacement with 
serviceable blades. This amendment is prompted by reports of a cracked 
composite propeller blade. The actions specified in this AD are 
intended to prevent propeller blade cracks and propagation, which could 
result in propeller blade separation and possible aircraft loss of 
control.

DATES: Effective September 16, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of September 16, 1999.
    Comments for inclusion in the Rules Docket must be received on or 
before November 1, 1999.

ADDRESSES: Submit comments to the Federal Aviation Administration 
(FAA), New England Region, Office of the Regional Counsel, Attention: 
Rules Docket No. 99-NE-43-AD, 12 New England Executive Park, 
Burlington, MA 01803-5299. Comments may also be sent via the Internet 
using the following address: <a href="/cdn-cgi/l/email-protection#b8d8d88195d9d6dd95d9dcdbd7d5d5ddd6ccf8ded9d996dfd7ce">``<span class="__cf_email__" data-cfemail="dae3f7bbb4bff7bbbeb9b5b7b7bfb4ae9abcbbbbf4bdb5ac">[email&#160;protected]</span></a>''. Comments sent 
via the Internet must contain the docket number in the subject line.
    The service information referenced in this AD may be obtained from 
Dowty Aerospace Propellers, Anson Business Park, Cheltenham Road East, 
Gloucester GL29QN, England; telephone +44 1452 716000, fax +44 1452 
716001. This information may be examined at the FAA, New England 
Region, Office of the Regional 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.

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 (781) 238-7158, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION: The Civil Aviation Authority (CAA), which is 
the airworthiness authority for the United Kingdom (UK), recently 
notified the Federal Aviation Administration (FAA) that an unsafe 
condition may exist on Dowty Aerospace Propellers Model R381/6-123-F/5 
propellers. The CAA advises that they have received a report of a crack 
that had developed on a de-iced propeller blade assembly across the 
camber face at a blade station of approximately 13.5'' up from the base 
of the blade cuff. Engineering evaluation of X-ray examination and 
subsequent CAT scan inspections of the camber face of the spar 
indicated a crack had developed internally from a composite defect in 
the spar and had propagated outward through the blade skin. The 
defective blade was found visually during a pre-flight pilot walk-
around inspection. The results of this pre-flight inspection resulted 
in removal of the propeller and replacement of the de-iced propeller 
blade assembly by maintenance crews. This condition, if not corrected, 
could result in propeller blade cracks and propagation, which could 
result in propeller blade separation and possible aircraft loss of 
control.

Service Information

    Dowty Aerospace Propellers has issued Service Bulletin (SB) No. 
S2000-61-75, Revision 1, dated June 11, 1999, that specifies procedures 
for visual and ultrasonic (UT) inspections of propeller blades for 
cracks across the camber face, and provides reject procedures for 
cracked blades. The CAA classified this SB as mandatory and issued 
Airworthiness Directive (AD) 003-05-99 in order to assure the 
airworthiness of these propellers in the UK.
    This propeller model is manufactured in the UK and is type 
certificated for operation in the United States under the provisions of 
Sec. 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.

Required Actions

    Since an unsafe condition has been identified that is likely to 
exist or develop on other propellers of the same type design registered 
in the United States, this AD requires initial and repetitive visual 
inspections for blade cracks at intervals of 50 hours time-in-service 
(TIS), and UT inspections at intervals of 200 hours TIS. Blades found 
cracked must be replaced with serviceable blades prior to further 
flight. The actions would be required to be accomplished in accordance 
with the SB described previously.

Interim Action

    The manufacturer is reviewing the design of the propeller blades 
and changes to the manufacturing process; hence future rulemaking may 
be forthcoming requiring installation of improved blades or changes to 
the inspection procedures.
    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 99-NE-43-AD.'' 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

[[Page 47663]]

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. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

99-18-18  Dowty Aerospace Propellers: Amendment 39-11284. Docket 99-
NE-43-AD.

    Applicability: Dowty Aerospace Propellers Model R381/6-123-F/5 
propellers, installed on but not limited to SAAB 2000 series 
airplanes.

    Note 1: This airworthiness directive (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 (c) 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: Required as indicated, unless accomplished 
previously.
    To prevent propeller blade cracks and propagation, which could 
result in propeller blade separation and possible aircraft loss of 
control, accomplish the following:

Visual Inspections

    (a) Perform initial and repetitive visual inspections of 
propeller blades for cracks across the camber face in accordance 
with the Accomplishment Instructions of Dowty Aerospace Propellers 
Service Bulletin (SB) No. S2000-61-75, Revision 1, dated June 11, 
1999, as follows:
    (1) Initially inspect within 50 hours time-in-service (TIS) 
after the effective date of this AD.
    (2) Thereafter, inspect at intervals not to exceed 50 hours TIS 
since last inspection.
    (3) Replace cracked propeller blades prior to further flight 
with serviceable blades.

Ultrasonic (UT) Inspections

    (b) Perform initial and repetitive UT inspections of propeller 
blades for cracks across the camber face in accordance with the 
Accomplishment Instructions of Dowty Aerospace Propellers SB No. 
S2000-61-75, Revision 1, dated June 11, 1999, as follows:
    (1) Initially inspect within 200 hours TIS after the effective 
date of this AD.
    (2) Thereafter, inspect at intervals not to exceed 200 hours TIS 
since last inspection.
    (3) Replace cracked propeller blades prior to further flight 
with serviceable blades.
    (c) 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 (ACO). 
Operators shall submit their requests through an appropriate FAA 
Principal Maintenance Inspector, who may add comments and then send it 
to the Manager, Boston ACO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the Boston ACO.
    (d) Special flight permits may be issued in accordance with 
Secs. 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 
inspection requirements of this AD can be accomplished.
    (e) The actions required by this AD shall be performed in 
accordance with Dowty Aerospace Propellers SB No. S2000-61-75, 
Revision 1, dated June 11, 1999. 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 
Aerospace Propellers, Anson Business Park, Cheltenham Road East, 
Gloucester GL29QN, England; telephone +44 1452 716000, fax +44 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 Office of the Federal Register, 800 North 
Capitol Street, NW, suite 700, Washington, DC.
    (f) This amendment becomes effective on September 16, 1999.

    Issued in Burlington, Massachusetts, on August 25, 1999.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 99-22563 Filed 8-31-99; 8:45 am]
BILLING CODE 4910-13-U

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