[Federal Register Volume 69, Number 209 (Friday, October 29, 2004)]
[Proposed Rules]
[Pages 63104-63106]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-24230]


========================================================================
Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

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Federal Register / Vol. 69, No. 209 / Friday, October 29, 2004 / 
Proposed Rules

[[Page 63104]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2004-18024; Directorate Identifier 2003-NE-39-AD]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce (1971) Limited, Bristol 
Engine Division Model Viper Mk.601-22 Turbojet Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) for Rolls-Royce (1971) Limited, Bristol Engine Division 
(RR) model Viper Mk.601-22 turbojet engines. That AD currently requires 
reducing the life of certain 1st stage turbine rotor blades from 7,000 
hours time-in-service (TIS) to 4,600 hours TIS, and provides a drawdown 
schedule for blades that have already exceeded the new reduced life 
limit. This proposed AD would require the same actions but changes 
certain compliance times to be in agreement with RR Alert Service 
Bulletin (ASB) No. 72-A184, dated January 2001. This proposed AD 
results from comments received on AD 2004-13-03, that the AD is 
unnecessarily more restrictive than the requirements in the associated 
RR ASB No. 72-A184. We are proposing this AD to prevent multiple 
failures of 1st stage turbine rotor blades that could result in a dual-
engine shutdown.

DATES: We must receive any comments on this proposed AD by December 28, 
2004.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
    <bullet> DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
    <bullet> Government-wide rulemaking Web site: Go to 1http://
www.regulations.gov and follow the instructions for sending your 
comments electronically.
    <bullet> Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590.
    <bullet> Fax: (202) 493-2251.
    <bullet> Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    You can get the service information identified in this proposed AD 
from Rolls-Royce Limited, Bristol Engines Division, Technical 
Publications Department CLS-4, P.O. Box 3, Filton, Bristol, BS34 7QE 
England; telephone 117-979-1234, fax 117-979-7575.
    You may examine the comments on this proposed AD in the AD docket 
on the Internet at http://dms.dot.gov.

FOR FURTHER INFORMATION CONTACT: Ian Dargin, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-
7178; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Docket Management System (DMS)

    We have implemented new procedures for maintaining AD dockets 
electronically. As of May 17, 2004, we posted new AD actions on the DMS 
and assigned a DMS docket number. We track each action and assign a 
corresponding Directorate identifier. The DMS docket No. is in the form 
``Docket No. FAA-200X-XXXXX.'' Each DMS docket also lists the 
Directorate identifier (``Old Docket Number'') as a cross-reference for 
searching purposes.

Comments Invited

    We invite you to submit any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2004-18024; 
Directorate Identifier 2003-NE-39-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://dms.dot.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 
DMS Web site, anyone can find and read the comments in any of our 
dockets, including 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), or you 
may visit http://dms.dot.gov.

Examining the AD Docket

    You may examine the docket that contains the proposal, any comments 
received and any final disposition in person at the DMS Docket Offices 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Office (telephone (800) 647-5227) is located on 
the plaza level of the Department of Transportation Nassif Building at 
the street address stated in ADDRESSES. Comments will be available in 
the AD docket shortly after the DMS receives them.

Discussion

    On June 16, 2004, the FAA issued AD 2004-13-03, Amendment 39-13684 
(69 FR 34563, June 22, 2004). That AD requires reducing the life of 
certain 1st stage turbine rotor blades from 7,000 hours TIS to 4,600 
hours TIS, and provides a drawdown schedule for blades that have 
already exceeded the new reduced life limit. That AD was the result of 
the manufacturer's investigations into failures of 1st stage turbine 
rotor blades. That condition, if not corrected, could result in 
multiple failures of 1st stage turbine rotor blades that could result 
in a dual-engine shutdown.

Comments Received Since AD 2004-13-03 Was Issued

    Since we issued final rule; request for comments AD 2004-13-03, we 
have considered the comments received.

Paragraph (g)(4) in Table 1 Is More Restrictive Than the SB

    One commenter requests that we revise paragraph (g)(4) in Table 1 
so that

[[Page 63105]]

the limits are only applicable to engines with 5,800 hours TIS or more. 
As currently written, that paragraph is more restrictive than RR ASB 
No. 72-A184, dated January 2001, and not consistent with it.
    We agree. Based on paragraph (g)(4) of AD 2004-13-03, it is 
possible that an engine with fewer than 5,800 hours TIS, but exceeding 
either the 200-hour or 6-month limit from the effective date of the AD, 
would have to be removed from service. The intent was that after 6 
months from the effective date of the AD and up to 3 years from the 
effective date of the AD, engines be allowed to operate up to a maximum 
of 5,800 hours TIS. We have rewritten the second column for paragraph 
(g)(4) in Table 1 of this proposal as follows:
    ``Replace the engine that has the higher blade life at 5,800 hours 
TIS or 6 months after the effective date of this AD, whichever occurs 
later.''
    We have also added a new paragraph (h) to this proposal as follows:
    ``(h) No engine may operate with a blade life exceeding 5,800 hours 
TIS, applicable beginning 6 months after the effective date of this 
AD.''

Paragraph (h) Is More Restrictive Than the SB

    One commenter requests that we revise paragraph (h) of AD 2004-13-
03, so that it is not more restrictive than RR ASB No. 72-A184, dated 
January 2001, and is consistent with it.
    We agree. The intent of paragraph (h) of AD 2004-13-03 was to 
remove all engines with blades exceeding 4,600 hours TIS, applicable 
within 3 years after the effective date of the AD. This wording is not 
clear and could apply to an engine, for example, with 1,000 hours TIS. 
This would force the engine off wing after 3 years while the engine may 
have only accumulated an additional 1,000 hours TIS, which is far short 
of the intended life limit. It is important to delineate between the 
near term ``drawdown'' schedule which limits blade life to 5,800 hours 
TIS per Table 1, beginning at 6 months and continuing up to 3 years 
from the effective date of the AD, and the ``objective'' life limit of 
4,600 hours TIS which begins at 3 years from the effective date of this 
AD. We have removed the existing paragraph (h) from this proposal and 
recodified the paragraphs. We have added a new paragraph (i) to this 
proposal as follows:
    ``(i) No engine may operate with a blade life exceeding 4,600 hours 
TIS, applicable beginning 3 years after the effective date of this 
AD.''

Relevant Service Information

    We have reviewed and approved the technical contents of RR Alert 
Service Bulletin (ASB) 72-A184, dated January 2001, that describes 
procedures for managing engine configurations to reduce the risk of 
dual-engine shutdowns. The CAA classified this service bulletin as 
mandatory and issued AD 004-01-2001 in order to ensure the 
airworthiness of these RR engines in the UK.

Differences Between This Proposed AD and the Service Information

    RR ASB 72-A184, dated January 2001, specifies the date of receipt 
of the ASB as the baseline for the compliance time. This proposed AD 
specifies the effective date of the AD as the baseline for the 
compliance time.

Bilateral Agreement Information

    This engine model is manufactured in the UK 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. Under this bilateral 
airworthiness agreement, the CAA has kept the FAA informed of the 
situation described above. We have 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.

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.
    The unsafe condition described previously is likely to exist or 
develop on other RR Viper Mk.601-22 turbojet engines of the same type 
design. We are issuing this AD to prevent multiple failures of 1st 
stage turbine rotor blades that could result in a dual-engine shutdown. 
We are proposing this AD which would:
    <bullet> Reduce the recommended class B life of certain 1st stage 
turbine blades, P/Ns V926000, V926293 and V926319, from 7,000 hours TIS 
to a mandatory life limit of 4,600 hours TIS, and
    <bullet> Provide a drawdown schedule for engines with blades that 
have already exceeded the new reduced life limit.

Costs of Compliance

    We estimate that 84 RR model Viper Mk.601-22 turbojet engines 
installed on airplanes of U.S. registry would be affected by this 
proposed AD. We estimate that no additional labor cost will be incurred 
to replace 1st stage turbine rotor blades when done at time of engine 
overhaul. A replacement set 1st stage turbine rotor blades costs about 
$166,987. Based on these figures, we estimate the total cost of the 
proposed AD to U.S. operators to be $14,026,950.

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 
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. 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 summary of the costs to comply with this proposal and 
placed it in the AD Docket. You may get a copy of this summary at the 
address listed under ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, 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 39-13684 (69 FR 
34563, June 22, 2004) and by adding a new airworthiness directive, to 
read as follows:

Rolls-Royce (1971) Limited, Bristol Engine Division: Docket No. FAA-
2004-18024; Directorate Identifier 2003-NE-39-AD. Supersedes AD 
2004-13-03, Amendment 39-13684.

[[Page 63106]]

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by December 28, 
2004.

Affected ADs

    (b) This AD supersedes AD 2004-13-03, Amendment 39-13684.

Applicability

    (c) This AD applies to Rolls-Royce (1971) Limited, Bristol 
Engine Division (RR) Model Viper Mk.601-22 turbojet engines. These 
engines are installed on, but not limited to, Raytheon HS.125 Series 
600 and BH.125 Series 600 airplanes.

Unsafe Condition

    (d) This AD results from comments received on AD 2004-13-03, 
that the AD is unnecessarily more restrictive than the requirements 
in the associated RR Alert Service Bulletin (ASB) No. 72-A184. We 
are proposing this AD to prevent multiple failures of 1st stage 
turbine rotor blades that could result in a dual-engine shutdown. 
The actions specified in this AD are intended to prevent multiple 
failures of 1st stage turbine rotor blades that could result in a 
dual-engine shutdown.

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.

New Reduced Life Limit

    (f) Change the RR Time Limits Manual life limit for the 1st 
stage turbine rotor blades, P/Ns V926000, V926293, and V926319, from 
7,000 hours time-in-service (TIS) to 4,600 hours TIS.
    (g) Limit the number of installed engines with 1st stage turbine 
rotor blades that exceed 4,600 hours TIS on the effective date of 
this AD as specified in the following Table 1:

                       Table 1.--Installed Engines
------------------------------------------------------------------------
  On the effective date of this AD, if                Then:
------------------------------------------------------------------------
(1) Both engines installed on the        Replace the 1st stage turbine
 airplane have 1st stage turbine rotor    rotor blades in the engine
 blades that exceed 5,800 hours TIS.      that has the higher blade life
                                          within 50 hours TIS or 6 weeks
                                          after the effective date of
                                          this AD, whichever occurs
                                          first.
(2) One engine installed on the          Replace the 1st stage turbine
 airplane has 1st stage turbine rotor     rotor blades in the engine
 blades that exceed turbine 5,800 hours   that has the higher blade life
 TIS, and the other engine has 1st        within 100 hours TIS or 4
 stage turbine rotor blades that exceed   months after the effective
 4,600 hours TIS.                         date of this AD, whichever
                                          occurs first.
(3) One engine installed on the          Replace the 1st stage turbine
 airplane has 1st stage turbine rotor     rotor blades in the engine
 blades that exceed 5,800 hours TIS,      that has the higher blade life
 and the other engine has 1st stage       within 200 hours TIS or 6
 turbine rotor blades with fewer than     months after the effective
 4,600 hours TIS.                         date of this AD, whichever
                                          occurs first.
(4) One engine installed on the          Replace the 1st stage rotor
 airplane has 1st stage turbine rotor     blades in the engine that has
 blades that exceed 4,600 hours TIS,      the higher blade life at 5,800
 but have fewer than 5,800 hours TIS,     hours TIS or 6 months after
 and the other engine has 1st turbine     the effective date of this AD,
 stage turbine rotor blades with fewer    whichever occurs later.
 than 4,600 hours TIS.
------------------------------------------------------------------------

    (h) No engine may operate with a blade life exceeding 5,800 
hours TIS, applicable beginning 6 months from the effective date of 
this AD.
    (i) No engine may operate with a blade life exceeding 4,600 
hours TIS, applicable beginning 3 years from the effective date of 
this AD.

Installation of Engines After the Effective Date of This AD

    (j) After the effective date of this AD, do not install any 
engine that has 1st stage turbine rotor blades, P/Ns V926000, 
V926293, and V926319, that exceed 4,600 hours TIS, except as allowed 
in Table 1 of this AD.

Alternative Methods of Compliance

    (k) 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

Material Incorporated by Reference

    (l) None.

Related Information

    (m) Civil Aviation Authority airworthiness directive AD 004-01-
2001, dated January 2001, also addresses the subject of this AD.

    Issued in Burlington, Massachusetts, on October 25, 2004.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 04-24230 Filed 10-28-04; 8:45 am]
BILLING CODE 4910-13-P