[Federal Register: November 3, 2003 (Volume 68, Number 212)]
[Rules and Regulations]
[Page 62228-62231]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr03no03-9]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2003-NE-40-AD; Amendment 39-13357; AD 2003-22-09]
RIN 2120-AA64
Airworthiness Directives; Pratt & Whitney PW4074, PW4074D,
PW4077, PW4077D, PW4084, PW4084D, PW4090, PW4090D, PW4090-3, and PW4098
Turbofan Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; request for comments.
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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
Pratt & Whitney PW4074, PW4074D, PW4077, PW4077D, PW4084, PW4084D,
PW4090, PW4090D, PW4090-3, and PW4098 turbofan engines. This AD
requires borescope inspection of the No. 3 bearing weep tube, on
engines with high oil consumption that troubleshooting procedures fail
to determine the source of oil loss. This AD also requires for all
engines, initial and repetitive visual inspections of the turbine
exhaust case (TEC) in the vicinity of the No 3 bearing oil vent tube
for evidence of oil wetting or staining. If the vent tube borescope
inspection is unsuccessful due to tube blockage, this AD also requires
borescope inspections of the high pressure turbine (HPT) assembly for
oil wetting or staining. This AD also requires removal of the HPT
assembly and replacement of any heat distressed HPT assembly hardware
if oil wetting or staining is found. This AD is prompted by reports of
engine HPT assembly hardware being damaged as a result of thermal
distress from oil
[[Page 62229]]
igniting after leaking from the No. 3 bearing compartment. We are
issuing this AD to prevent thermal distressed HPT assembly hardware
from remaining in service, which could result in a cracked HPT stage 1
disk or HPT stage 1-2 air seal and an uncontained engine failure.
DATES: Effective December 3, 2003. The Director of the Federal Register
approved the incorporation by reference of certain publications listed
in the regulations as of December 3, 2003.
We must receive any comments on this AD by January 2, 2004.
ADDRESSES: Use one of the following addresses to submit comments on
this AD:
[sbull] By mail: The Federal Aviation Administration (FAA), New
England Region, Office of the Regional Counsel, Attention: Rules Docket
No. 2003-NE-40-AD, 12 New England Executive Park, Burlington, MA 01803-
5299.
[sbull] By fax: (781) 238-7055. [sbull] By e-mail: 9-ane-adcomment@faa.gov.
You can get the service information referenced in this AD from
Pratt & Whitney, 400 Main St., East Hartford, CT 06108; telephone (860)
565-7700; fax (860) 565-1605.
You may examine the AD docket, by appointment, at the FAA, New
England Region, Office of the Regional Counsel, 12 New England
Executive Park, Burlington, MA. You may examine the service
information, by appointment, 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: Keith Lardie, Aerospace Engineer,
Engine Certification Office, FAA, Engine and Propeller Directorate, 12
New England Executive Park, Burlington, MA 01803-5299; telephone (781)
238-7189; fax (781) 238-7199.
SUPPLEMENTARY INFORMATION: The FAA is aware of seven reports of Pratt &
Whitney PW4074, PW4074D, PW4077, PW4077D, PW4084, PW4084D, PW4090,
PW4090D, PW4090-3, and PW4098 turbofan engines with HPT thermal
distress caused by ignition of oil in cavities of the HPT assembly.
This oil ignition was the result of oil leaking from the No. 3 bearing
compartment. Five of those engines were approaching or exceeded high
oil consumption limits. Four of the engines had distress resulting in
significant damage to the HPT assembly. Over time, the increased
temperatures from oil ignition can cause cracking of the HPT stage 1
disk anti-rotation lugs and HPT stage 1-2 air seal that may result in
an uncontained engine failure. The root cause of the oil leakage is
currently unknown. The manufacturer suspects the following three
causes:
[sbull] Clogging of the oil passages on the No. 3 seal plates.
[sbull] Wear on the anti-rotation slots on the No. 3 carbon seal
carriers.
[sbull] Loose stack of the No. 3 bearing compartment.
Relevant Service Information
We have reviewed and approved the technical contents of Pratt &
Whitney Alert Service Bulletin (ASB) No. PW4G-112-A72-257, Revision 1,
dated August 22, 2003, that describes procedures for:
[sbull] Borescope inspection of the No. 3 bearing weep tube, on
engines with high oil consumption that troubleshooting procedures fail
to determine the source of oil loss.
[sbull] For all engines, initial and repetitive visual inspections
of the TEC, in the vicinity of the No. 3 bearing oil vent tube assembly
and borescope inspections of the No. 3 bearing oil vent tube assembly,
for evidence of oil wetting or staining.
[sbull] Borescope inspection of the HPT assembly for evidence of
oil wetting or staining if the borescope inspection of the No. 3
bearing oil vent tube assembly is unsuccessful due to blockage.
[sbull] Removal of the engine if oil wetting or staining is found.
Differences Between This AD and the Service Information
Although ASB No. PW4G-112-A72-257, Revision 1, dated August 22,
2003, requires removal of the engine from service if oil wetting or
staining is found, this AD requires removal of the HPT assembly and
replacement of any heat distressed HPT assembly hardware if oil wetting
or staining is found.
FAA's Determination and Requirements of This AD
The unsafe condition described previously is likely to exist or
develop on other Pratt & Whitney PW4074, PW4074D, PW4077, PW4077D,
PW4084, PW4084D, PW4090, PW4090D, PW4090-3, and PW4098 turbofan engines
of the same type design. We are issuing this AD to prevent thermal
distressed HPT assembly hardware to remain in service, which could
result in a cracked HPT stage 1 disk or HPT stage 1-2 air seal and an
uncontained engine failure. This AD requires:
[sbull] Borescope inspection of the No. 3 bearing weep tube on
engines with high oil consumption that troubleshooting procedures fail
to determine the source of oil loss.
[sbull] For all engines, initial and repetitive visual inspections
of the TEC, in the vicinity of the No. 3 bearing oil vent tube assembly
and borescope inspections of the No. 3 bearing oil vent tube assembly,
for evidence of oil wetting or staining.
[sbull] Borescope inspections of the HPT assembly for oil wetting
or staining, if the vent tube borescope inspection is unsuccessful due
to tube blockage.
[sbull] Removal of the HPT assembly and replacement of any heat
distressed HPT assembly hardware if oil wetting or staining is found.
You must use the service information described previously to perform
the actions required by this AD.
FAA's Determination of the Effective Date
Since an unsafe condition exists that requires the immediate
adoption of this AD, we have found that notice and opportunity for
public comment before issuing this AD are impracticable, and that good
cause exists for making this amendment effective in less than 30 days.
Changes to 14 CFR Part 39--Effect on the AD
On July 10, 2002, we issued a new version of 14 CFR part 39 (67 FR
47998, July 22, 2002), which governs our AD system. This regulation now
includes material that relates to special flight permits, alternative
methods of compliance, and altered products. 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.
Interim Action
These actions are interim actions and we may take further
rulemaking actions in the future, when the manufacturer's investigation
is completed.
Comments Invited
This AD is a final rule that involves requirements affecting flight
safety and was not preceded by notice and an opportunity for public
comment; however, we invite you to submit any written relevant data,
views, or arguments regarding this AD. Send your comments to an address
listed under ADDRESSES. Include ``AD Docket No. 2003-NE-40-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
[[Page 62230]]
you. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify it. If a person contacts us verbally, and that
contact relates to a substantive part of this 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 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 with 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.
Regulatory Findings
We have determined that this AD will not have federalism
implications under Executive Order 13132. This AD 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.
For the reasons discussed above, I certify that the 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. 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.
We prepared a summary of the costs to comply with this AD 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-40-AD'' in your request.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
0
Accordingly, under 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
0
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]
0
2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive:
2003-22-09 Pratt & Whitney: Amendment 39-13357. Docket No. 2003-NE-
40-AD.
Effective Date
(a) This airworthiness directive (AD) becomes effective December
3, 2003.
Affected ADs
(b) None.
Applicability: (c) This AD applies to Pratt & Whitney PW4074,
PW4074D, PW4077, PW4077D, PW4084, PW4084D, PW4090, PW4090D, PW4090-
3, and PW4098 turbofan engines. These engines are installed on, but
not limited to, Boeing 777 series airplanes.
Unsafe Condition
(d) This AD is prompted by reports of engine high pressure
turbine (HPT) assembly hardware being damaged as a result of thermal
distress from oil igniting after leaking from the No. 3 bearing
compartment. We are issuing this AD to prevent thermal distressed
HPT assembly hardware from remaining in service, which could result
in a cracked HPT stage 1 disk and HPT stage 1-2 air seal and 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.
Credit for Previous Inspections
(f) Inspections performed before the effective date of this AD,
using Pratt & Whitney Alert Service Bulletin (ASB) No. PW4G-112-A72-
257, dated June 30, 2003, may be counted toward satisfying the
initial and repetitive inspection requirements of paragraphs (g)
through (k) of this AD.
Borescope Inspection of Engines With High Oil Consumption
(g) For engines with high oil consumption that troubleshooting
procedures fail to determine the source of oil loss, borescope-
inspect No. 3 bearing oil vent tube assembly and or HPT assembly
within 100 cycles-in-service (CIS) of the high oil consumption
event, using paragraphs (g)(1) through (g)(2) of this AD.
Information on troubleshooting engines with high oil consumption can
be found in Boeing 777 Fault Isolation Manual (FIM), section 71-05,
Task 830, dated January 5, 2003. See paragraph (l) of this AD for a
definition of high oil consumption.
(1) Borescope-inspect the No. 3 bearing oil vent tube assembly
for evidence of oil wetting or staining. Follow Step 3, paragraphs
1. through 1.A.(8)(a) of Accomplishment Instructions of Pratt &
Whitney ASB No. PW4G-112-A72-257, Revision 1, dated August 22, 2003.
(2) If the No. 3 bearing oil vent tube is blocked and attempts
to clear it are unsuccessful, borescope-inspect the HPT assembly,
following Step 4, paragraphs 1. through 1.B(14) of Accomplishment
Instructions of ASB No. PW4G-112-A72-257, Revision 1, dated August
22, 2003.
(3) Remove the HPT assembly within 100 CIS of the high oil
consumption event if evidence of oil wetting or staining is found in
the No. 3 bearing oil vent tube or on the HPT first stage disk.
(4) Replace any heat distressed HPT assembly hardware if oil
wetting or staining is found.
Turbine Exhaust Case (TEC) Inspections Of All Engines
(h) Inspect the TEC of all engines, within 500 hours-in-service
(HIS) after the effective date of this AD as follows:
(1) Visually inspect the TEC in the vicinity of the No. 3
bearing oil vent tube assembly for evidence of oil wetting or
staining, using Figure 2 of Pratt & Whitney ASB No. PW4G-112-A72-
257, Revision 1, dated August 22, 2003, for location of inspection.
(2) If evidence of oil wetting or staining is found at the TEC,
borescope-inspect the No. 3 bearing oil vent tube assembly within
100 additional CIS, to confirm the oil is from the vent tube. Follow
Step 1, paragraphs 1.B. through 1.D.(8)(a) of Accomplishment
Instructions of Pratt & Whitney ASB No. PW4G-112-A72-257, Revision
1, dated August 22, 2003.
(3) If the No. 3 bearing oil vent tube is blocked and attempts
to clear it are unsuccessful, borescope-inspect the HPT assembly
following Step 4, paragraphs 1. through 1.B.(14) of Accomplishment
Instructions of ASB No. PW4G-112-A72-257, Revision 1, dated August
22, 2003.
(4) Remove the HPT assembly within 100 CIS since performing the
visual inspection of the TEC specified in paragraph (h)(1) of this
AD, if evidence of oil wetting or staining is found in the No. 3
bearing oil vent tube or found on the HPT first stage disk.
(5) Replace any heat distressed HPT assembly hardware if oil
wetting or staining is found.
Borescope Inspections of All Engines
(i) Borescope-inspect the No. 3 bearing oil vent tube assembly
of all engines at or before accumulating 600 CIS or 2,000 HIS,
whichever occurs first, after the effective date of this AD, as
follows:
(1) Borescope-inspect the No. 3 bearing oil vent tube assembly
for evidence of oil wetting or staining. Follow Step 2, paragraphs
1. through 1.A.(8) of Accomplishment Instructions of Pratt & Whitney
ASB No. PW4G-112-A72-257, Revision 1, dated August 22, 2003.
(2) If the No. 3 bearing oil vent tube is blocked and attempts
to clear it are unsuccessful, borescope-inspect the HPT assembly
following Step 4, paragraphs 1. through 1.B.(14) of Accomplishment
[[Page 62231]]
Instructions of ASB No. PW4G-112-A72-257, Revision 1, dated August
22, 2003.
(3) Remove the HPT assembly within 100 CIS since performing the
visual inspection of the TEC specified in paragraph (h)(1) of this
AD, if evidence of oil wetting or staining is found in the No. 3
bearing oil vent tube or found on the HPT first stage disk.
(4) Replace any heat distressed HPT assembly hardware if oil
wetting or staining is found.
Repetitive Inspections of All Engines
(j) Repeat the inspections of the TEC of all engines by
following paragraphs (h)(1) through (h)(3) of this AD, at intervals
not to exceed 500 HIS since last visual check of the TEC, and
disposition the engine as specified in paragraphs (h)(4) through
(h)(5) of this AD.
(k) Repeat borescope inspections of all engines by following
paragraphs (i)(1) through (i)(2) of this AD, at intervals not to
exceed 600 CIS or 2,000 HIS since last borescope inspection of the
No. 3 oil vent tube, and disposition the engine as specified in
paragraphs (i)(3) through (i)(4) of this AD.
Definition
(l) For the purposes of this AD, high oil consumption is defined
as an engine consuming more than 0.5 quarts of oil per hour, as
provided in the Boeing 777 FIM.
Alternative Methods of Compliance
(m) 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
(n) You must follow Pratt & Whitney Alert Service Bulletin
specified in Table 1 to perform the inspections required by this AD.
The Director of the Federal Register approved the incorporation by
reference of this service bulletin in accordance with 5 U.S.C.
552(a) and 1 CFR part 51. You can get a copy from Pratt & Whitney,
400 Main St., East Hartford, CT 06108; telephone (860) 565-7700; fax
(860) 565-1605. You may review copies 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.
Table 1.--Incorporation by Reference
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Alert service bulletin No. Page Nos. Revision Date
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PW4G-112-A72-257....................... 1-5 1........................ August 22, 2003.
6-7 Original................. June 30, 2003.
8 1........................ August 22, 2003.
9 Original................. June 30, 2003.
10 1........................ August 22, 2003.
11 Original................. June 30, 2003.
12 1........................ August 22, 2003.
13-22 Original................. June 30, 2003.
Total pages: 22
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Related Information
(o) Boeing 777 Fault Isolation Manual, section 71-05, Task 830,
dated January 5, 2003, pertains to high oil consumption
troubleshooting procedures referred to in this AD.
Issued in Burlington, Massachusetts, on October 24, 2003.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 03-27327 Filed 10-31-03; 8:45 am]
BILLING CODE 4910-13-P