[Federal Register Volume 65, Number 8 (Wednesday, January 12, 2000)]
[Proposed Rules]
[Pages 1840-1841]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-722]



[[Page 1840]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NE-50-AD]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce Ltd. Dart 511, 511-7E, 514-
7, 528, 528-7E, 529-7E, 532-7, 532-7L, 532-7N, 532-7P, 532-7R, 535-7R, 
551-7R, and 552-7R Turboprop Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to Rolls-Royce Ltd. (R-R) Dart 511, 
511-7E, 514-7, 528, 528-7E, 529-7E, 532-7, 532-7L, 532-7N, 532-7P, 532-
7R, 535-7R, 551-7R, and 552-7R turboprop engines. This proposal would 
require the installation of a feathering probe and a steel retaining 
ring in the reduction gear housing (RGH), and replacement of a transfer 
bobbin installed in the torquemeter. This proposal is prompted by two 
reports of the failure of a propeller to feather following the failure 
of the RGH annulus gear, which resulted in the propeller overspeeding 
and the release of a propeller blade, causing damage to the airplane. 
The actions specified by the proposed AD are intended to prevent a 
propeller from overspeeding and the release of a propeller blade after 
a failure of the RGH annulus gear, which could result in damage to an 
adjacent engine or to the airplane.

DATES: Comments must be received by March 13, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), New England Region, Office of the Regional 
Counsel, Attention: Rules Docket No. 99-NE-50-AD, 12 New England 
Executive Park, Burlington, MA 01803-5299. Comments may also be 
submitted to the Rules Docket by using the following Internet address: 
``[email protected].'' Comments may be inspected at this location 
between 8 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 Rolls-Royce Limited, Attn: Dart Engine Service Manager, 
East Kilbride, Glasgow G74 4PY, Scotland; telephone: 011-44-1355-220-
200, fax: 011-44-1141-778-432. This information may be examined at the 
FAA, New England Region, Office of the Regional Counsel, 12 New England 
Executive Park, Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Jason Yang, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803-5299; telephone 781-238-
7747, 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 in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before acting 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-50-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-50-AD, 12 New England Executive Park, 
Burlington, MA 01803-5299.

Discussion

    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 R-R 
Dart 511, 511-7E, 514-7, 528, 528-7E, 529-7E, 532-7, 532-7L, 532-7N, 
532-7P, 532-7R, 535-7R, 551-7R, and 552-7R turboprop engines. The CAA 
advises that there has been an incident where the RGB annulus gear 
failed, which resulted in the malfunctioning of an engine in service. 
Manual feathering of the propeller was initiated, but the propeller 
failed to feather. The propeller disconnected from the gearbox and 
oversped to the point where it separated. This caused extensive damage 
to the adjacent engine and to the airplane fuselage.

Service Information

    R-R has issued service bulletin (SB) Da72-348, Revision 13, dated 
December 22, 1998, that specifies modification instructions for:
     Installation of a probe to trigger a low-torque switch, 
which will automatically feather the propeller in the event of a 
failure of the annulus gear.
     Installation of a steel retaining ring between the nose 
casing and the front bearing panel to maintain engagement between the 
annulus gear teeth and layshafts following a gear failure.
     Replacement of a transfer bobbin with a new design that 
allows a more rapid torquemeter oil pressure drop in order to initiate 
the auto feather function.
    The CAA classified this service bulletin as mandatory and issued AD 
1935 in order to assure the airworthiness of these R-R Dart 511, 511-
7E, 514-7, 528, 528-7E, 529-7E, 532-7, 532-7L, 532-7N, 532-7P, 532-7R, 
535-7R, and 551-7R, 552-7R turboprop engines in the U.K.

Difference Between Service Bulletin Information and This AD

    R-R SB Da72-348, Revision 13, dated December 22, 1998, requires 
that the probe and retaining ring be installed before December 31, 
2000. The FAA has determined that the probe and ring should be 
installed at the next engine shop visit or by December 31, 2000, 
whichever occurs first.

Bilateral Airworthiness Agreement

    This engine model is manufactured in the U.K. and is 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

[[Page 1841]]

certificated for operation in the United States.

Requirements of This AD

    Since an unsafe condition has been identified that is likely to 
exist or develop on other R-R Dart 511, 511-7E, 514-7, 528, 528-7E, 
529-7E, 532-7, 532-7L, 532-7N, 532-7P, 532-7R, 535-7R, 551-7R, and 552-
7R turboprop engines of the same type design registered in the United 
States, the proposed AD would require:
     Installation of a feathering probe.
     Installation of a steel retaining ring in the reduction 
gear housing.
     Replacement of a torquemeter oil pressure transfer bobbin.

The actions would be required to be accomplished at the next shop visit 
after the effective date of the proposed AD, or by December 31, 2000, 
whichever occurs first, in accordance with the service bulletin 
described previously.

Cost Impact

    There are approximately 1500 engines of the affected design in the 
worldwide fleet. The FAA estimates that 100 engines installed on 
aircraft of U.S. registry would be affected by this proposed AD, that 
it would take approximately 2 work hours per engine to accomplish the 
proposed actions and that the average labor rate is $60 per work hour. 
Required parts would cost approximately $300 per engine. Based on these 
figures, the total cost impact of the proposed AD on U.S. operators is 
estimated to be $42,000.

Regulatory Impact

    This proposed 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 proposed rule.
    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. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

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

Rolls Royce Ltd.: Docket No. 99-NE-50-AD.

    Applicability: Rolls-Royce Ltd. (R-R) Dart 511, 511-7E, 514-7, 
528, 528-7E, 529-7E, 532-7, 532-7L, 532-7N, 532-7P, 532-7R, 535-7R, 
551-7R, and 552-7R turboprop engines, installed on but not limited 
to Fokker Aircraft B.V. F27 series and Maryland Air Industries 
(formerly Fairchild) F-27 and FH-227 series airplanes.

    Note 1: This airworthiness directive (AD) applies to each engine 
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 engines 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 a propeller from overspeeding resulting in propeller 
release after a failure of the annulus gear, which could result in 
damage to an adjacent engine or to the airplane, accomplish the 
following:

Installation of a Sensor Probe and Retaining Ring

    (a) At the next shop visit after the effective date of this AD, 
or by December 31, 2000, whichever occurs first, do all of the 
following:
    (1) Install a feathering probe in the front bearing panel of the 
reduction gearbox in accordance with paragraph 2.A. of service 
bulletin (SB) Da72-348, revision 13, dated April 13, 1999.
    (2) Install a steel retaining ring between the nose casing and 
the front bearing panel in accordance with paragraph 2.C. of SB 
Da72-348, revision 13, dated April 13, 1999.
    (3) Replace the existing transfer bobbin with an aluminum bobbin 
in accordance with paragraph 2.C. of SB Da72-348, revision 13, dated 
April 13, 1999.

Definition of a Shop Visit

    (b) For the purposes of this AD, a shop visit is defined as any 
maintenance action that results in the removal or disassembly of the 
reduction gearbox.

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, Engine Certification Office (ECO). 
Operators shall submit their request through an appropriate FAA 
Principal Maintenance Inspector, who may add comments and then send 
it to the Manager, ECO.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the ECO.

    (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 requirements of this AD can be accomplished.

    Issued in Burlington, Massachusetts, on January 5, 2000.
Thomas A. Boudreau,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service
[FR Doc. 00-722 Filed 1-11-00; 8:45 am]
BILLING CODE 4910-13-P