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###### Department of Transportation

###### Federal Aviation Administration 

          - 14 CFR Part 39 
          - [Docket No. FAA-2008-0752; Directorate Identifier 2008-NE-22-AD] 
          - RIN 2120-AA64 

# AGENCY:

Federal Aviation Administration (FAA), DOT. 

# ACTION:

Notice of proposed rulemaking (NPRM). 

# SUMMARY:

We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed 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 follows:

                            There have been several reported incidents of high altitude, dual engine flameout on JT15D-5 engines powered aircraft operating in certain meteorological conditions. Subsequent to the investigation of incidents,                                   ( print page 49620)                                review of the engine design has revealed that the Fuel Control Hydro Mechanical Unit (HMU) P3 servo can be exposed to excessive moisture and freezing.                        

We are proposing this AD to prevent engine flameout, and possible dual-engine flameout events, caused by excessive moisture and freezing in the P3 servo, during certain flight conditions. 

# DATES:

We must receive comments on this proposed AD by September 22, 2008. 

# ADDRESSES:

You may send comments by any of the following methods: 
      -  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.                     

## 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.                 

# FOR FURTHER INFORMATION CONTACT:

                        Ian Dargin, Aerospace Engineer, Engine Certification Office, FAA, Engine and 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:

## Comments Invited 

                    We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the                     **ADDRESSES**                     section. Include “Docket No. FAA-2008-0752; Directorate Identifier 2008-NE-22-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD based on 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, 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).                 

## Discussion 

Transport Canada, which is the aviation authority for Canada, has issued Canadian AD CF-2008-23, dated June 27, 2008 (referred to after this as “the MCAI”), to correct an unsafe condition for the specified products. The MCAI states the following:

There have been several reported incidents of high altitude, dual engine flameout on JT15D-5 engine powered aircraft operating in certain meteorological conditions. Subsequent to the investigation of incidents, review of the engine design has revealed that the Fuel Control HMU P3 servo can be exposed to excessive moisture and freezing. To preclude P3 servo freezing, P&WC has issued JT15D ASB No. JT15D-72-A7611 to re-route compressor delivery air to the HMU and improve moisture separation.

You may obtain further information by examining the MCAI in the AD docket. 

## Relevant Service Information 

P&WC has issued ASB No. JT15D-72-A7611, Revision 1, dated June 16, 2008. The actions described in this service information are intended to correct the unsafe condition identified in the MCAI. 

## FAA's Determination and Requirements of This Proposed AD 

This product has been approved by the aviation authority of Canada, and is approved for operation in the United States. Pursuant to our bilateral agreement with Canada, they have notified us of the unsafe condition described in the MCAI and service information referenced above. We are proposing this AD because we evaluated all the information provided by Canada and determined the unsafe condition exists and is likely to exist or develop on other products of the same type design. This proposed AD requires replacing the compressor air to HMU delivery tube with a new, re-routed tube. The new tube provides warmer and dryer P3 air, improves moisture separation, and directs the moisture away from the HMU through a drain hole. 

## Costs of Compliance 

Based on the service information, we estimate that this proposed AD would affect about 1,500 products of U.S. registry. We also estimate that it would take about 3 work-hours per product to comply with this proposed AD. The average labor rate is $80 per work-hour. Required parts would cost about $1,981 per product for JT15D-5 and -5R engines, and $3,169 per product for JT15D-5B and -5R engines. Based on these figures, we estimate the cost of the proposed AD on U.S. operators to be $4,222,500. 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 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 this 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. Will not have a significant economic impact, positive or negative,                           ( print page 49621)                        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 and placed it in the AD docket. 

# 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 FAA 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. 

§ 39.13 

2. The FAA amends § 39.13 by adding the following new AD:

**Pratt & Whitney Canada:**                                 Docket No. FAA-2008-0752; Directorate Identifier 2008-NE-22-AD.                             

## Comments Due Date 

(a) We must receive comments by September 22, 2008. 

## Affected Airworthiness Directives (ADs) 

(b) None. 

## Applicability 

(c) This AD applies to the following Pratt & Whitney Canada (P&WC) turbofan engines with compressor air to HMU delivery tube, part number (P/N) 3119150-01 installed: 

(1) JT15D-5 turbofan engines, serial numbers (SNs) below and including SN PCE-100411. 

(2) JT15D-5 turbofan engines, SNs below and including SN PCE-JA0818. 

(3) All JT15D-5B turbofan engines. 

(4) All JT15D-5F turbofan engines. 

(5) JT15D-5R turbofan engines SNs below and including SN PCE-JG0104. 

(6) All JT15D-5 turbofan engines converted to model JT15D-5R by incorporation of P&WC Service Bulletin No. 7605. 

These engines are installed on, but not limited to, Cessna models 500; 501; 550; 551; S550; 560; and 560 Ultra airplanes; Mitsubishi models 300 and 300-10 airplanes; and Hawker Beechcraft models 400; 400A; and 400T airplanes. 

## Reason

(d) Transport Canada AD CF-2008-23, dated June 27, 2008, states:

There have been several reported incidents of high altitude, dual engine flameout on JT15D-5 engines powered aircraft operating in certain meteorological conditions. Subsequent to the investigation of incidents, review of the engine design has revealed that the Fuel Control Hydro Mechanical Unit (HMU) P3 servo can be exposed to excessive moisture and freezing. To preclude P3 servo freezing, P&WC has issued JT15D Alert Service Bulletin (ASB) JT15D-72-A7611 to re-route compressor delivery air to the HMU and improve moisture separation. Considering the potentially hazardous consequence of possible in-flight dual engine flameout, this airworthiness directive is issued to mandate the incorporation of P&WC ASB JT15D-72-A7611 to the affected JT15D-5 engines, in order to minimize the possibility of this hazard. 

We are issuing this AD to prevent engine flameout, and possible dual-engine flameout events, caused by excessive moisture and freezing in the P3 servo, during certain flight conditions. 

## Actions and Compliance 

(e) Unless already done, do the following actions. 

(1) Within 200 flight hours after the effective date of this AD or by December 31, 2008, whichever occurs first, remove from service compressor air to HMU delivery tube, P/N 3119150-01. 

(2) Install a serviceable compressor air to HMU delivery tube. 

(3) Tube installation in accordance with P&WC Alert Service Bulletin (ASB) No. JT15D-72-A7611, Revision 1, dated June 16, 2008, meets the requirements of this AD. 

## Prohibition of Compressor Air to HMU Delivery Tube, P/N 3119150-01 

(4) After the effective date of this AD, do not install any compressor air to HMU delivery tube, P/N 3119150-01, onto any engine. 

## Definition 

(f) For the purpose of this AD, a serviceable compressor air to HMU delivery tube is a compressor air to HMU delivery tube that is other than the old/removed tube part number listed in this AD. 

                                (g)                                 *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.                             

## Previous Credit 

(h) Replacement of the compressor air to HMU delivery tube using P&WC ASB No. JT15D-72-A7611, dated March 26, 2008, before the effective date of this AD, meets the requirements of this AD. 

## Related Information 

(i) Refer to Transport Canada AD CF-2008-23, dated June 27, 2008, for related information. 

                                (j) Contact Ian Dargin, Aerospace Engineer, Engine Certification Office, FAA, Engine and 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.                             

Issued in Burlington, Massachusetts, on August 15, 2008. 

Robert G. Mann, 

Acting Manager, Engine and Propeller Directorate, Aircraft Certification Service.

 [FR Doc. E8-19390 Filed 8-21-08; 8:45 am] 

BILLING CODE 4910-13-P