

[Federal Register: November 9, 2007 (Volume 72, Number 217)]
[Proposed Rules]               
[Page 63508-63510]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr09no07-20]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-24825; Directorate Identifier 2006-NE-17-AD]
RIN 2120-AA64

 
Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG 
(RRD) Dart 528, 529, 532, 535, 542, and 552 Series Turboprop Engines

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) for (RRD) Dart 528, 529, 532, 535, 542, and 552 Series 
turboprop engines. That AD currently requires a dimensional inspection 
of the intermediate pressure turbine (IPT) disk or an ultrasonic 
inspection of the seal arm contact between the high pressure turbine 
(HPT) and the IPT disk seal arm and reworking or replacing the IPT disk 
if worn beyond acceptable limits. This proposed AD would continue to 
require those actions. This proposed AD results from us including an 
incorrect engine model and omitting an engine model from the 
applicability of the existing AD. We are proposing this AD to prevent 
HPT disk failure, which can result in an uncontained engine failure and 
damage to the airplane.

DATES: We must receive any comments on this proposed AD by January 8, 
2008.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD.
     Federal eRulemaking Portal: Go to http://www.regulations.gov
 and follow the instructions for sending your 

comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 1200 New Jersey Avenue, SE., West Building Ground 
Floor, Room W12-140, Washington, DC 20590-0001.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
     Fax: (202) 493-2251.
    Contact Rolls-Royce Deutschland Ltd & Co KG, Eschenweg 11, D-15827 
Dahlewitz, Germany; telephone 49 (0) 33-7086-1768; fax 49 (0) 33-7086-
3356 for the service information identified in this proposed AD.

FOR FURTHER INFORMATION CONTACT: Jason Yang, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; telephone (781) 238-7747; 
fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2006-24825; 
Directorate Identifier 2006-NE-17-AD'' in the subject line of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the proposed AD. We will 
consider all comments received by the closing date and may amend the 
proposed AD in light of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov
, including any personal information you provide. We 

will also post a report summarizing each substantive verbal contact 
with FAA personnel concerning this proposed AD. Using the search 
function of the Web site, anyone can find and read the comments in any 
of our dockets,

[[Page 63509]]

including, if provided, the name of the individual who sent the comment 
(or signed the comment on behalf of an association, business, labor 
union, etc.). You may review the DOT's complete Privacy Act Statement 
in the Federal Register published on April 11, 2000 (65 FR 19477-78).

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov
; or in person at the Docket Operations office 

between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Operations office (telephone (800) 647-5527) is 
the same as the Mail address provided in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.

Discussion

    On January 12, 2007, the FAA issued AD 2007-02-07, Amendment 39-
14894 (72 FR 2610, January 12, 2007). That AD requires a dimensional 
inspection of the IPT disk or an ultrasonic inspection of the seal arm 
contact between the HPT and the IPT disk seal arm and reworking or 
replacing the IPT disk if worn beyond acceptable limits. That AD was 
the result of reports of a number of HPT disk failures, some of which 
resulted in released portions of the HPT disk. That condition, if not 
corrected, could result in HPT disk failure, which can result in an 
uncontained engine failure and damage to the airplane.

Actions Since AD 2007-02-07 Was Issued

    Since we issued AD 2007-02-07, we found that we listed Dart 555 
series turboprop engines, which don't exist, and we omitted Dart 552 
series engines from the AD. We are proposing this AD to delete Dart 555 
series engines from the applicability paragraph of this proposed AD and 
to list Dart 552 series turboprop engines in the applicability 
paragraph of this proposed AD.

Relevant Service Information

    We have reviewed and approved the technical contents of RRD DART 
Service Bulletin (SB) Da72-536, Revision 1, dated August 25, 2003, and 
SB Da72-538, dated June 10, 2005. SB Da72-536 describes procedures for 
conducting an ultrasonic inspection to determine if a gap exists 
between the HPT and IPT disk seal arms. SB Da72-538 describes 
procedures for a dimensional inspection of the IPT disk and rework or 
replacement of the IPT disk if wear outside acceptable limits is found. 
The LBA classified this SB as mandatory and issued airworthiness 
directive D-2005-197, dated June 30, 2005, in order to ensure the 
airworthiness of these engines in Germany.

Differences Between the Proposed AD and the Service Information

    Because the service information was developed before the proposed 
AD, the compliance times permitted to conduct the inspections differ.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other products 
of this same type design. For that reason, we are proposing this AD, 
which would require a dimensional inspection of the IPT disk or an 
ultrasonic inspection of seal arm contact between the HPT and the IPT 
disk seal arm, and rework or replacement of the IPT disk, if wear 
outside acceptable limits is found. The proposed AD would require you 
to use the service information described previously to perform these 
actions.

Costs of Compliance

    We estimate that this proposed AD would affect 30 RRD Dart 528, 
529, 532, 535, 542, and 552 series turbofan engines installed on 
airplanes of U.S. registry. We also estimate that it would take about 
50 work-hours per engine to perform the proposed actions, and that the 
average labor rate is $80 per work-hour. Required parts would cost 
about $50,000 per IPT disk. We estimate that 25 percent, or eight 
engines, would require IPT disk replacement. Based on these figures, we 
estimate the total cost of the proposed AD to U.S. operators to be 
$500,000.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify that the proposed AD:
    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. Would not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD. See the ADDRESSES section for a location 
to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Under the authority delegated to me by the Administrator, the 
Federal Aviation Administration proposes to amend 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. The FAA amends Sec.  39.13 by removing Amendment 39-14894 (72 FR 
2610, January 12, 2007) and by adding a new airworthiness directive to 
read as follows:

Rolls-Royce Deutschland Ltd & Co KG (formerly Rolls-Royce plc): 
Docket No. FAA-2006-24825; Directorate Identifier 2006-NE-17-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by January 8, 
2008.

[[Page 63510]]

Affected ADs

    (b) This AD supersedes AD 2007-02-17, Amendment 39-14894.

Applicability

    (c) This AD applies to Rolls-Royce Deutschland Ltd & Co KG (RRD) 
Dart 528, 529, 532, 535, 542, and 552 series turboprop engines. 
These engines are installed on, but not limited to, Hawker Siddeley, 
Argosy AW.650, Fairchild Hiller F-27, F-27A, F-27B, F-27F, F-27G, F-
27J, FH-227, FH-227B, FH-227C, FH-227D, FH-227E, Fokker F.27 all 
marks; British Aircraft Corporation Viscount 744, 745D and 810; and 
Gulfstream G-159 airplanes.

Unsafe Condition

    (d) This AD results from us including an incorrect engine model 
and omitting an engine model from the applicability of the existing 
AD. We are issuing this AD to prevent HPT disk failure, which can 
result in an uncontained engine failure and damage to the airplane.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified unless the 
actions have already been done.

Intermediate Pressure Turbine (IPT) Disk and High Pressure Turbine 
(HPT)/IPT Disk Seal Arm Inspections

    (f) Within 60 days after the effective date of the AD, do either 
of the following:
    (1) Perform a dimensional inspection of the IPT disk and repair 
or replace the IPT disk, if necessary using paragraph 3 of the 
Accomplishment Instructions of RRD service bulletin (SB) Da72-538, 
dated June 10, 2005; or
    (2) Perform an ultrasonic inspection of the disk seal arm 
contact between the HPT and the IPT using paragraph 3 of the 
Accomplishment Instructions of RRD SB Da72-536, Revision 1, dated 
August 25, 2003.
    (i) For RRD Dart 528, 529, 532, 535, 542 series turboprop 
engines if wear is outside allowable limits, before June 30, 2007, 
perform a dimensional inspection and repair or replace the IPT disk, 
if necessary. Use paragraph 3 of the Accomplishment Instructions of 
RRD SB Da72-538, dated June 10, 2005.
    (ii) For RRD Dart 552 series turboprop engines if wear is 
outside allowable limits, before April 30, 2008, perform a 
dimensional inspection and repair or replace the IPT disk, if 
necessary. Use paragraph 3 of the Accomplishment Instructions of RRD 
SB Da72-538, dated June 10, 2005.
    (iii) If wear is within allowable limits, perform a dimensional 
inspection of the IPT disk at the next engine shop visit or at next 
overhaul, whichever occurs first and repair or replace the IPT disk, 
if necessary. Use paragraph 3 of the Accomplishment Instructions of 
RRD SB Da72-538, dated June 10, 2005.

Alternative Methods of Compliance

    (g) The Manager, Engine Certification Office, has the authority 
to approve alternative methods of compliance for this AD if 
requested using the procedures found in 14 CFR 39.19.

Related Information

    (h) LBA airworthiness directive D-2005-197, dated June 30, 2005, 
also addresses the subject of this AD.
    (i) Contact Jason Yang, Aerospace Engineer, Engine Certification 
Office, FAA, Engine and Propeller Directorate, 12 New England 
Executive Park, Burlington, MA 01803; telephone (781) 238-7747, fax 
(781) 238-7199; e-mail: jason.yang@faa.gov, for more information 
about this AD.

    Issued in Burlington, Massachusetts, on November 2, 2007.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
 [FR Doc. E7-22003 Filed 11-8-07; 8:45 am]

BILLING CODE 4910-13-P
