
[Federal Register: July 9, 2009 (Volume 74, Number 130)]
[Rules and Regulations]               
[Page 32802-32803]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr09jy09-4]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2009-0046; Directorate Identifier 2008-NE-05-AD; 
Amendment 39-15962; AD 2009-14-12]
RIN 2120-AA64

 
Airworthiness Directives; Pratt & Whitney Canada Corp. (P&WC) 
Models PW305A and PW305B Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for the 
products listed above. This AD results from mandatory continuing 
airworthiness information (MCAI) issued by an aviation authority of 
another country to identify and correct an unsafe condition on an 
aviation product. The MCAI describes the unsafe condition as:

    P&WC has determined that the Post-Service Bulletin (SB) PW300-
72-24287 High Pressure Compressor (HPC) drum rotor assemblies P/N 
30B2478 and 30B2542 on PW 305A and 305B engines with single stage 
coated labyrinth seals, are susceptible to developing significant 
cracks in the region of the labyrinth seal.

We are issuing this AD to detect cracks in the HPC drum rotor assembly, 
which could lead to an uncontained failure of the drum rotor assembly 
and damage to the airplane.

DATES: This AD becomes effective August 13, 2009.

ADDRESSES: The Docket Operations office is located at Docket Management 
Facility, U.S. Department of Transportation, 1200 New Jersey Avenue, 
SE., West Building Ground Floor, Room W12-140, Washington, DC 20590-
0001.

FOR FURTHER INFORMATION CONTACT: Ian Dargin, Aerospace Engineer, Engine 
Certification Office, FAA, Engine & Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
ian.dargin@faa.gov; telephone (781) 238-7178; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an AD that would apply to the specified products. 
That NPRM was published in the Federal Register on February 20, 2009 
(74 FR 7836). That NPRM proposed to correct an unsafe condition for the 
specified products. The MCAI states:

    P&WC has determined that the Post-Service Bulletin (SB) PW300-
72-24287 High Pressure Compressor (HPC) drum rotor assemblies P/N 
30B2478 and 30B2542 on PW 305A and 305B engines with single stage 
coated labyrinth seals, are susceptible to developing significant 
cracks in the region of the labyrinth seal.
    P&WC issued SB PW300-72-24462 for initial inspection of affected 
HPC drum rotor assemblies for cracks. In addition, the PW305 
Maintenance Manual (MM) 05-20-00 was revised (Revision No. 26) 
accordingly, to add requirement for repeat inspection interval. A 
new P/N 31B6325-01, HPC drum rotor assembly, which is not 
susceptible to subject cracking, is made available through SB PW300-
72-24376, as terminating action for the required repeat inspection.
    Recent data (Ref: SIL: PW300-093) indicate that a number of 
high-time Pre-SB-PW300-72-24376 HPC drum rotor assemblies (P/N 
30B2478 and 30B2542), with potential for a hazardous disk failure in 
consequence of non-compliance with the inspection requirements, are 
still in-service. This AD is issued to mandate the inspection of the 
affected P/N 30B2478 and 30B2542 HPC drum rotor assemblies in 
accordance with PW305-MM-05-20-00 requirements.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We received no comments on the NPRM or on the determination of 
the cost to the public.

Conclusion

    We reviewed the available data and determined that air safety and 
the public interest require adopting the AD as proposed.

Costs of Compliance

    Based on the service information, we estimate that this AD will 
affect about 540 products of U.S. registry. We also estimate that it 
will take about 10 work-hours per product to comply with this AD. The 
average labor rate is $80 per work-hour. Required parts will cost about 
$5,000 per product. Based on these figures, we estimate the cost of the 
AD on U.S. operators to be $3,132,000. Our cost estimate is exclusive 
of possible warranty coverage.

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 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 this 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. 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.

[[Page 32803]]

    We prepared a regulatory evaluation of the estimated costs to 
comply with this AD and placed it in the AD docket.

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 AD, the regulatory evaluation, 
any comments received, and other information. The street address for 
the Docket Operations office (telephone (800) 647-5527) is provided in 
the ADDRESSES section. Comments will be available in the AD docket 
shortly after receipt.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the FAA amends 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 AD:

2009-14-12 Pratt & Whitney Canada Corp: Amendment 39-15962. Docket 
No. FAA-2009-0046; Directorate Identifier 2008-NE-05-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective August 
13, 2009.

Affected ADs

    (b) None.
    (c) This AD applies to Pratt & Whitney Canada Corp. (P&WC) 
Models PW305A and PW305B turbofan engines with high pressure 
compressor (HPC) drum rotor assemblies, post P&WC Service Bulletin 
(SB) PW300-72-24287 but without P&WC SB PW300-72-24376, installed. 
These engines are installed on, but not limited to, Bombardier 
Learjet M60 and Hawker Beechcraft 1000 series airplanes.

Reason

    (d) P&WC has determined that the Post-Service Bulletin (SB) 
PW300-72-24287 High Pressure Compressor (HPC) drum rotor assemblies 
P/N 30B2478 and 30B2542 on PW305A and 305B engines with single stage 
coated labyrinth seals, are susceptible to developing significant 
cracks in the region of the labyrinth seal.

We are issuing this AD to detect cracks in the HPC drum rotor 
assembly, which could lead to an uncontained failure of the drum 
rotor assembly and damage to the airplane.

Actions and Compliance

    (e) Unless already done, do the following actions.
    (1) Within 500 flight hours after effective date of this 
directive, borescope-inspect the interiors of affected HPC rotor 
assemblies for cracks. If a crack is found, remove the engine before 
next flight for HPC drum rotor replacement. Pratt & Whitney 
Maintenance Manual, Chapter 72-00-00, contains guidance on borescope 
inspection.

Credit for Previous Inspections

    (2) Inspection of affected HPC drum rotor assembly per P&WC SB 
PW300-72-24462 and or SB PW305 MM 05-20-00 inspection requirements 
prior to the effective date of this directive satisfies the 
requirements of paragraph (e)(1) of this AD.
    (3) Repeat borescope inspection per paragraph (e)(1) of this AD, 
at intervals not exceeding 1,350 flight cycles. If a crack is found, 
remove the engine before next flight for HPC rotor drum replacement.

Optional Terminating Action

    (4) Replacement of the affected HPC rotor assembly P/N 30B2478 
or 30B2542 with Post-SB PW300-72-24376 assembly P/N 31B6325-01 or 
later superseding P/N, will constitute terminating action for the 
inspection requirements of the above paragraphs (e)(1) and (e)(2) of 
the corrective action requirements of this AD.

Other FAA AD Provisions

    (f) Alternative Methods of Compliance (AMOCs): The Manager, 
Engine Certification Office, FAA, has the authority to approve AMOCs 
for this AD, if requested using the procedures found in 14 CFR 
39.19.

Related Information

    (g) Refer to Canadian Airworthiness Directive CF-2007-25R1, 
dated February 13, 2008, and P&WC SB PW300-72-24462, dated December 
13, 1999, for related information. Contact Pratt & Whitney Canada 
Corp., 1000 Marie-Victorin, Longueuil, Quebec, Canada J4G 1A1, 
telephone: (800) 268-8000, for a copy of this service information.
    (h) Contact Ian Dargin, Aerospace Engineer, Engine Certification 
Office, FAA, Engine & Propeller Directorate, 12 New England 
Executive Park, Burlington, MA 01803; e-mail: ian.dargin@faa.gov; 
telephone (781) 238-7178; fax (781) 238-7199, for more information 
about this AD.

Material Incorporated by Reference

    (i) None.

    Issued in Burlington, Massachusetts, on June 30, 2009.
Francis A. Favara,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. E9-16111 Filed 7-8-09; 8:45 am]

BILLING CODE 4910-13-P
