Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-7, PC-12, and PC-12/45 Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede Airworthiness Directive (AD) 2002-01-09, which applies to all Pilatus Aircraft Ltd. (Pilatus) Models PC-7, PC-12, and PC-12/45 airplanes that incorporate a certain engine-driven pump. AD 2002-01-09 currently requires you to inspect the joints between the engine-driven pump housing, the relief valve housing, and the relief valve cover for signs of fuel leakage and extruding gasket material; replace any engine-driven pump with any of the above problems; and ensure that the relief valve attachment screws are adequately torqued and re-torque as necessary. This proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. This proposed AD would retain the actions from AD 2002-01-09, would add certain engine-driven pumps to the applicability, and would require eventual replacement of the pump with an improved design pump to assure that the unsafe condition does not recur. We are issuing this proposed AD to detect and correct gasket material extruding from the engine-driven pump housing and detect and correct relief valve attachment screws with inadequate torque. These conditions could lead to fuel leakage and result in a fire in the engine compartment.

DATES:

We must receive any comments on this proposed AD by January 6, 2004.

ADDRESSES:

Use one of the following to submit comments on this proposed AD:

• By mail: FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2003-CE-45-AD, 901 Locust, Room 506, Kansas City, Missouri 64106.
• By fax: (816) 329-3771.
• By e-mail: 9-ACE-7-Docket@faa.gov. Comments sent electronically must contain “Docket No. 2003-CE-45-AD” in the subject line. If you send comments electronically as attached electronic files, the files must be formatted in Microsoft Word 97 for Windows or ASCII.

You may get the service information identified in this proposed AD from Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans, Switzerland; telephone: +41 41 619 63 19; facsimile: +41 41 619 6224; or from Pilatus Business Aircraft Ltd., Product Support Department, 11755 Airport Way, Broomfield, Colorado 80021; telephone: (303) 465-9099; facsimile: (303) 465-6040.

You may view the AD docket at FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2003-CE-45-AD, 901 Locust, Room 506, Kansas City, Missouri 64106. Office hours are 8 a.m. to 4 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT:

Doug Rudolph, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4059; facsimile: (816) 329-4090.

SUPPLEMENTARY INFORMATION:

Comments Invited

How Do I Comment on This Proposed AD?

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-CE-45-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.

Are There Any Specific Portions of This Proposed AD I Should Pay Attention to?

We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. If you contact us through a nonwritten communication 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 this proposed AD in light of those comments and contacts.

Discussion

Has FAA Taken Any Action to This Point?

Reports of fuel leaking from certain engine-driven pumps on Pilatus Models PC-7, PC-12, and PC-12/45 airplanes caused FAA to issue AD 2002-01-09, Amendment 39-12600 (67 FR 2323, January 17, 2002). AD 2002-01-09 currently requires the following on all Pilatus Models PC-7, PC-12, and PC-12/45 airplanes:

—Inspecting the joints between the engine-driven pump housing, the relief valve housing, and the relief valve cover for signs of fuel leakage and extruding gasket material;

—Replacing any engine-driven pump with signs of fuel leakage or extruding gasket material; and

—Ensuring that the relief valve attachment screws are adequately torqued and re-torquing as necessary.

What Has Happened Since AD 2002-01-09 To Initiate This Proposed Action?

The Federal Office for Civil Aviation (FOCA), which is the airworthiness authority for Switzerland, recently notified FAA of the need to change AD 2002-01-09. The CAA reports that problems are occurring on other engine-driven pumps that could be installed on the affected airplanes, and that the affected airplanes should have a certain engine-driven pump installed to ensure this unsafe condition does not reoccur.

What Are the Consequences if the Condition Is Not Corrected?

Gasket material extruding from the engine-driven pump housing and relief valve attachment screws with inadequate torque, if not detected and corrected, could lead to fuel leakage and result in a fire in the engine compartment.

Is There Service Information That Applies to This Subject?

Pilatus has issued the following service information:

—Pilatus PC-7 Service Bulletin No. 28-007, Revision No. 1, dated October 1, 2002, which includes procedures for changing the diaphragm and valve housing assembly of the engine-driven pump, Lear Romec part number (P/N) RG9570M1 (Pilatus P/N 968.84.51.105) or Lear Romec P/N RG9570M (Pilatus P/N 968.84.51.103). This service bulletin also specifies incorporating Crane Lear Romec Service Bulletin SB9570-73-002 or Crane Lear Romec Service Bulletin RG9570-73-006;

—Pilatus PC-12 Service Bulletin No. 28-010, dated September 16, 2002, which includes procedures for changing the diaphragm and valve housing assembly of the engine-driven pump, Lear Romec P/N RG9570R1 (Pilatus P/N 968.84.51.106). This service bulletin also specifies incorporating Crane Lear Romec Service Bulletin SB9570-73-002; and

—Pilatus PC-7 Service Bulletin No. 28-008, Revision 1, dated September 24, 2002, which specifies procedures for inspecting the engine-driven pump, Lear Romec P/N RG9570M (Pilatus P/N 968.84.51.103) for signs of fuel leakage or extruding gasket material and correcting relief valve torque on the screws.

Does the Service Information From AD 2002-01-09 Still Apply?

Yes. Pilatus PC-7 Service Bulletin No. 28-006 and Pilatus PC-12 Service Bulletin No. 28-009, both dated August 10, 2001, are still valid and provide information on the inspection and replacement of the engine-driven pumps, Romec P/N RG9570M1 (Pilatus P/N 968.84.51.105) and Lear Romec P/N RG9570R1 (Pilatus P/N 968.84.51.106).

What Action Did the FOCA Take?

The FOCA classified these service bulletins as mandatory and issued FOCA AD HB 2003-392, dated September 15, 2003; and FOCA AD HB 2003-251, dated June16, 2003, to ensure the continued airworthiness of these airplanes in Switzerland.

Did the FOCA Inform the United States Per the Bilateral Airworthiness Agreement?

These Pilatus Models PC-7, PC-12, and PC-12/45 airplanes are manufactured in Switzerland and are 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 FOCA has kept us informed of the situation described above.

FAA's Determination and Requirements of This Proposed AD

What Has FAA decided?

We have examined the FOCA's findings, 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.

Since the unsafe condition described previously is likely to exist or develop on other Pilatus Models PC-7, PC-12, and PC-12/45 airplanes of the same type design that are registered in the United States, we are proposing AD action to detect and correct gasket material extruding from the engine-driven pump housing and detect and correct relief valve attachment screws with inadequate torque. These conditions could lead to fuel leakage and result in a fire in the engine compartment.

What Would This Proposed AD Require?

This proposed AD would supersede

AD 2002-01-09 with a new AD that would:

—Retain the actions from AD 2002-01-09;

—Add certain engine-driven pumps to the applicability; and

—Require eventual replacement of the pump with an improved design pump to assure that the unsafe condition does not reoccur.

How Does the Revision to 14 CFR Part 39 Affect This Proposed AD?

On July 10, 2002, we published a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs 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

How Many Airplanes Would This Proposed AD Impact?

We estimate that this proposed AD affects 278 airplanes in the U.S. registry.

What Would Be the Cost Impact of This Proposed AD on Owners/Operators of the Affected Airplanes?

We estimate the following costs to accomplish the proposed inspections and re-torque:

We estimate the following costs to accomplish any necessary replacements that would be required based on the results of the inspection. We have no way of determining the number of airplanes that may need such replacement:

What Is the Difference Between the Cost Impact of This Proposed AD and the Cost Impact of AD 2002-01-09?

The only difference between this proposed AD and AD 2002-01-09 is the addition of affected engine-driven pumps. The number of airplanes that could have an affected pump installed and the costs associated with inspection and replacement are the same.

Compliance Time of This Proposed AD

What Would Be the Compliance Time of the Proposed Inspection?

The compliance time of the inspections that would be required by this proposed AD is “within 20 hours time-in-service (TIS) after the effective date of this AD or within the next 30 days after the effective date of this AD, whichever occurs first.”

Why Is the Compliance Time of the Proposed Inspection Presented in Both Hours TIS and Calendar Time?

The deterioration and potential extrusion of the gasket occurs over time and is not a condition of repetitive airplane operation. However, the relief valve attachment screws becoming inadequately torqued occurs as a result of airplane operation if the compression set of the gasket and diaphragm after thermal cycling causes the gasket of the engine-driven pump to extrude between the relief valve housing and the engine-driven pump housing.

Therefore, to ensure that the unsafe condition defined in this document is detected and corrected in a timely manner, we are stating the compliance in both calendar time and hours TIS.

Regulatory Findings

Would This Proposed AD Impact Various Entities?

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.

Would This Proposed AD Involve a Significant Rule or Regulatory Action?

For the reasons discussed above, I certify that this proposed 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.

We prepared a summary of the costs to comply with this proposed 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-CE-45-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.