[Federal Register Volume 68, Number 172 (Friday, September 5, 2003)]
[Proposed Rules]
[Pages 52720-52721]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-22621]


 ========================================================================
 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.
 
 ========================================================================
 

  Federal Register / Vol. 68, No. 172 / Friday, September 5, 2003 / 
Proposed Rules  

[[Page 52720]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NE-34-AD]
RIN 2120-AA64


Airworthiness Directives; Pratt & Whitney JT9D-3A, -7, -7A, -7AH, 
-7H, -7F, -7J, -20, and -20J Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for Pratt & Whitney (PW) JT9D-3A, -7, -7A, -7AH, -7H, -7F, -7J, -20, 
and -20J turbofan engines. This proposed AD would clarify a life limit 
for certain part numbers of 6th stage low pressure turbine (LPT) air 
seals, and require their removal from service before accumulating 
15,000 cycles-since-new (CSN). This proposed AD is prompted by reports 
of certain 6th stage LPT air seals possibly not being life tracked due 
to confusion from updates to the engine manuals. We are proposing this 
AD to prevent failure of the 6th stage LPT air seal, which could cause 
LPT damage resulting in an uncontained engine failure.

DATES: We must receive any comments on this proposed AD by November 4, 
2003.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD:
    [sbull] By mail: Federal Aviation Administration (FAA), New England 
Region, Office of the Regional Counsel, Attention: Rules Docket No. 
2003-NE-34-AD, 12 New England Executive Park, Burlington, MA 01803-
5299.
    [sbull] By fax: (781) 238-7055.
    [sbull] By e-mail: [email protected].
    You can get the service information identified in this proposed AD 
from Pratt & Whitney, 400 Main St., East Hartford, CT 06108; telephone 
(860) 565-8770; fax (860) 565-4503.
    You may examine the AD docket at the FAA, New England Region, 
Office of the Regional Counsel, 12 New England Executive Park, 
Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Keith Lardie, Aerospace Engineer, 
Engine Certification Office, FAA, Engine & Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803-5299; telephone (781) 
238-7189; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

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 ``AD Docket No. 2003-NE-34-AD'' in the 
subject line of your comments. If you want us to acknowledge receipt of 
your mailed comments, send us a self-addressed, stamped postcard with 
the docket number written on it; we will date-stamp your postcard and 
mail it back to you. We specifically invite comments on the overall 
regulatory, economic, environmental, and energy aspects of the proposed 
AD. If a person contacts us verbally, and that contact relates to a 
substantive part of this proposed AD, we will summarize the contact and 
place the summary in the docket. We will consider all comments received 
by the closing date and may amend the proposed AD in light of those 
comments.
    We are reviewing the writing style we currently use in regulatory 
documents. We are interested in your comments on whether the style of 
this document is clear, and your suggestions to improve the clarity of 
our communications that affect you. You may get more information about 
plain language at http://www.faa.gov/language and http://www.plainlanguage.gov.

Examining the AD Docket

    You may examine the AD Docket (including any comments and service 
information), by appointment, between 8 a.m. and 4:30 p.m., Monday 
through Friday, except Federal holidays. See ADDRESSES for the 
location.

Discussion

    The FAA has recently been made aware that the life limit for 6th 
stage LPT air seals, part numbers (P/Ns) 808846, 809171, 811260 and 
811261, may not be clearly stated in Chapter 5 of the engine manuals. 
Proper life tracking of these parts is required to ensure safe 
operation of engines, but because of changes to the engine manuals some 
operators may have believed that some 6th stage LPT air seals may not 
require life tracking. This condition, if not corrected, could result 
in failure of the 6th stage LPT air seal, which could cause LPT damage 
resulting in an uncontained engine failure.

Relevant Service Information

    We have reviewed and approved the technical contents of PW Service 
Bulletin No. JT9D 6448, dated June 10, 2003, that describes procedures 
for calculating 6th stage LPT air seal part life for air seals that 
have not been previously life tracked.

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. Therefore, we are proposing this AD, which 
would clarify the life limit for 6th stage LPT air seals, P/Ns 808846, 
809171, 811260, and 811261, and require their removal from service 
before accumulating 15,000 CSN. The proposed AD would require you to 
use the service information described previously for calculating 6th 
stage LPT air seal part life for parts that have not been previously 
life tracked.

Changes to 14 CFR Part 39--Effect on the Proposed AD

    On July 10, 2002, we published a new version of 14 CFR part 39 (67 
FR 47997, July 22, 2002), which governs the FAA's AD system. This 
regulation now includes material that relates to altered products, 
special flight permits, and alternative methods of compliance. This 
material previously was included in each individual AD. Since this 
material is included in 14 CFR part 39, we will not include it in 
future AD actions.

Costs of Compliance

    There are about 1,024 engines of the affected design in the 
worldwide fleet. We estimate that 367 engines installed on airplanes of 
U.S. registry would be affected by this proposed AD. We also

[[Page 52721]]

estimate that it would take approximately 0.5 work hour per engine to 
calculate the 6th stage LPT air seal part life, and that the average 
labor rate is $65 per work hour. Based on these figures, we estimate 
the total cost of the proposed AD to U.S. operators to be $11,928.

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 by 
sending a request to us at the address listed under ADDRESSES. Include 
``AD Docket No. 2003-NE-34-AD'' in your request.

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 adding the following new 
airworthiness directive:

Pratt & Whitney: Docket No. 2003-NE-34-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by November 4, 
2003.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Pratt & Whitney (PW) JT9D-3A, -7, -7A, -
7AH, -7H, -7F, -7J, -20, and -20J turbofan engines. These engines 
are installed on, but not limited to, Boeing 747-100, 747-200, 
747SR, 747SP, and DC10-40 series airplanes.

Unsafe Condition

    (d) This proposed AD is prompted by reports of certain 6th stage 
low pressure turbine (LPT) air seals possibly not being life tracked 
due to confusion from updates to the engine manuals. Chapter 5 of 
Engine Manuals part numbers (P/Ns) 646028, 770407, and 770408 will 
be revised to show a life limit of 15,000 cycles-since-new (CSN) for 
6th stage air seal P/N's 808846, 809171, 811260 and 811261. We are 
issuing this AD to prevent failure of the 6th stage LPT air seal 
which could cause LPT damage, resulting in an uncontained engine 
failure.

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.

Determine Service Life

    (f) For 6th stage LPT air seals, P/Ns 808846, 809171, 811260, 
and 811261, with an unknown number of cycles since installed, 
calculate the service life within 60 days after the effective date 
of this AD.
    (1) Use Method 1 of the Accomplishment Instructions of PW 
Service Bulletin (SB) No. JT9D 6448, dated June 10, 2003, for when 
all service records are available for the specific air seal, to 
calculate the service life.
    (2) Use Method 2 of the Accomplishment Instructions of PW SB No. 
JT9D 6448, dated June 10, 2003, for when any or all service records 
are not available for a specific air seal, to calculate the service 
life. If the worst-case daily utilization rate is unknown, use the 
fleet worst-case daily utilization rate of 2.9 cycles/day.

Removal From Service

    (g) Remove 6th stage LPT air seals, P/Ns 808846, 809171, 811260, 
and 811261, from service at or before accumulating the CSN in the 
following Table 1.

                                 Table 1.--Part Number and Engine Applicability
----------------------------------------------------------------------------------------------------------------
                      Part No.                                 Engine applicability             Life limit CSN
----------------------------------------------------------------------------------------------------------------
808846 (old)........................................  JT9D-3A, -7, -7A, -7AH, -7H, -7F, -7J,             15,000
                                                       -20, -20J.
811260 (new)........................................  JT9D-3A, -7, -7A, -7AH, -7H, -7F, -7J,             15,000
                                                       -20, -20J.
809171 (old)........................................  JT9D-3A, -7, -7A, -7AH, -7H, -7F, -20.             15,000
811261 (new)........................................  JT9D-3A, -7, -7A, -7AH, -7H, -7F, -20.             15,000
----------------------------------------------------------------------------------------------------------------

    (h) If the service life cannot be determined as specified in 
paragraph (f) of this AD, remove the 6th stage LPT air seal before 
accumulating 2,500 cycles-in-service after the effective date of 
this AD.
    (i) After the effective date of this AD, do not install any 6th 
stage LPT air seal, P/N 808846, 809171, 811260, or 811261, that 
exceeds 15,000 CSN, or that was removed to comply with paragraph (h) 
of this AD because its service life could not be determined.

Alternative Methods of Compliance

    (j) 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

    (k) You must use Pratt & Whitney Service Bulletin No. JT9D 6448, 
dated June 10, 2003, to perform the service life calculations 
required by this AD. Approval of incorporation by reference from the 
Office of the Federal Register is pending.

Related Information

    (l) None.


    Issued in Burlington, Massachusetts, on August 28, 2003.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 03-22621 Filed 9-4-03; 8:45 am]
BILLING CODE 4910-13-P