[Federal Register Volume 65, Number 162 (Monday, August 21, 2000)]
[Proposed Rules]
[Pages 50667-50669]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-21167]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NE-43-AD]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking.

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SUMMARY: This document proposes to revise an existing airworthiness 
directive (AD) that is applicable to Dowty Aerospace Propellers Model 
R381/6-123-F/5 propellers. That action currently requires initial and 
repetitive visual and ultrasonic inspections of propeller blades for 
cracks across the camber face, and, if blades are found cracked, 
replacement with serviceable blades. This proposed revision would 
increase the time-in-service (TIS) intervals between required visual 
and ultrasonic inspections. This proposal is prompted by an engineering 
analysis of

[[Page 50668]]

field service data and certification testing that indicate that the 
repetitive inspection interval can be safely increased. The actions 
specified in this proposed revision are intended to prevent propeller 
blade cracks and propagation, which could result in propeller blade 
separation and possible aircraft loss of control.

DATES: Comments must be received by September 20, 2000.

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: ``[email protected]''. 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:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications should identify the Rules Docket number 
and be submitted 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 99-NE-43-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRM's

    Any person may obtain a copy of this NPRM by submitting a request 
to the 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.

Discussion

    On August 25, 1999, the FAA issued 99-NE-43-AD, Amendment 39-11284, 
(64 FR 47661, September 1, 1999), applicable to Dowty Aerospace 
Propellers Model R381/6-123-F/5 propellers to require initial and 
repetitive visual and ultrasonic inspections of propeller blades for 
cracks across the camber face, and, if blades are found cracked, 
replacement with serviceable blades. That action was prompted by a 
report of a crack that had developed on a deiced propeller blade 
assembly across the camber face at a blade station of approximately 
13.5" up from the base of the blade cuff. That 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. The FAA received no comments to the current AD, issued 
as a final rule, request for comments.
    Since that AD was issued an engineering analysis of field service 
data and certification testing indicate that the repetitive inspection 
interval can be safely increased. As a result, the manufacturer has 
revised Dowty Service Bulletin No. S2000-61-75 (Rev. 3, dated September 
30, 1999), to increase the repetitive visual inspection interval from 
50 to 300 hours time in service (TIS) since last inspection and 
repetitive visual and ultrasonic inspections of propeller blades for 
cracks from 200 to 600 hours TIS.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other Dowty Aerospace Propellers Model R381/6-123-
F/5 propellers of the same type design, the proposed AD would revise AD 
99-18-18 to increase the TIS intervals between required visual and 
ultrasonic inspections.

Regulatory Impact

    The proposed revision would not increase the economic burden on US 
operators as set out in the economic analysis published for the current 
AD.
    The regulations adopted herein will 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. Therefore, it 
is determined that this final rule does not have federalism 
implications under Executive Order 13132.
    The FAA has determined that this regulation 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, Safety.

The Proposed 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 removing Amendment 39-11284 (64 FR 
47661, September 1, 1999), and by adding a new airworthiness directive 
(AD), to read as follows:

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

[[Page 50669]]

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 3, dated September 
30, 1999, as follows:
    (1) Initially, conduct a visual inspection within 50 hours time-
in-service (TIS) after the effective date of the original AD.
    (2) Thereafter, inspect at intervals not to exceed 300 hours TIS 
since last inspection.
    (3) Replace cracked propeller blades prior to further flight 
with serviceable blades.

Ultrasonic Inspections

    (b) Perform initial and repetitive ultrasonic 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 3, dated September 30, 1999, as 
follows:
    (1) Initially inspect within 200 hours TIS after the effective 
date of the original AD.
    (2) Thereafter, inspect at intervals not to exceed 600 hours TIS 
since last inspection.
    (3) Replace cracked propeller blades prior to further flight 
with serviceable blades.

Alternative Method of Compliance

    (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.

Special Flight Permits

    (d) 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 inspection requirements of this AD can be accomplished.

    Issued in Burlington, Massachusetts, on August 14, 2000.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 00-21167 Filed 8-18-00; 8:45 am]
BILLING CODE 4910-13-U