Airworthiness directives: Pilatus Aircraft Ltd.,

[Federal Register: June 25, 1998 (Volume 63, Number 122)]

[Rules and Regulations]

[Page 34565-34567]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr25jn98-10]

[[Page 34565]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-CE-40-AD; Amendment 39-10608; AD 98-11-01 R1]

RIN 2120-AA64

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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Direct final rule; request for comments.

SUMMARY: This amendment revises Airworthiness Directive (AD) 98-11-01, which currently requires replacing the fuel tank vent valves and drilling a 4.8 millimeter (0.1875 inch) hole in each fuel filler cap on certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. AD 98-11-01 also requires inserting a temporary revision in the Pilot's Operating Handbook (POH) that specifies checking to assure that the fuel filler cap hole is clear of ice and foreign objects. This AD maintains the requirements of AD 98-11-01, and adds the option of modifying the fuel tank vent valves instead of the drilling and POH requirements carried over from AD 98-11-01. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified in this AD are intended to continue to prevent moisture from entering the fuel tank inward vent valve and then freezing after a cold soak at altitude, which could result in wing airfoil distortion and structural damage with consequent degradation of the airplane's handling qualities.

DATES: Effective September 22, 1998.

The incorporation by reference of Pilatus Service Bulletin No. 28- 003, Revision 1, dated September 30, 1997, as listed in the regulations, was previously approved by the Director of the Federal Register as of December 1, 1997 (62 FR 59993, November 6, 1997).

The incorporation by reference of Pilatus Service Bulletin No. 28- 004, dated March 27, 1998, as listed in the regulations, was previously approved by the Director of the Federal Register as of June 7, 1998 (63 FR 27195, May 18, 1998).

The incorporation by reference of Pilatus Service Bulletin No. 28- 005, dated May 4, 1998, is approved by the Director of the Federal Register as of September 22, 1998.

Comments for inclusion in the Rules Docket must be received on or before July 24, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 98-CE-40-AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

Service information that applies to this AD may be obtained from Pilatus Aircraft Ltd., CH-6370 Stans, Switzerland. This information may also be examined at the Federal Aviation Administration (FAA), Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 98- CE-40-AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106; or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Mr. Roman T. Gabrys, Aerospace Engineer, FAA, Small Airplane Directorate, 1201 Walnut, suite 900, Kansas City, Missouri 64106; telephone: (816) 426-6934; facsimile: (816) 426-2169.

SUPPLEMENTARY INFORMATION:

Discussion

On October 29, 1997, the FAA issued AD 97-23-04, mendment 39-10192 (62 FR 5993, November 6, 1997), which applies to certain Pilatus Models PC-12 and PC-12/45 airplanes. AD 97-23-04 was the result of a report from the Federal Office for Civil Aviation (FOCA), which is the airworthiness authority for Switzerland, of an instance of abnormal automatic engagement of the fuel booster pumps during normal operation of a Pilatus Model PC-12 airplane. The FOCA's investigation revealed that the fuel tank inward vent valves may fail in the closed position under certain conditions. Moisture ingestion, followed by cold soak, can lead to the fuel tank inward vent valve freezing.

AD 97-23-04 required replacing the fuel tank vent valves with modified fuel tank vent valves before the FAA superseded it with AD 98- 11-01, Amendment 39-10528 (63 FR 27195, May 18, 1998). AD 98-11-01 currently requires the fuel tank vent valves replacement required by AD 97-23-04, and requires drilling a 4.8 millimeter (0.1875 inch) hole in each fuel filler cap.

This AD also requires inserting the following temporary revision to the POH that specifies checking to assure that the fuel filler cap hole is clear of ice and foreign objects:

``PC-12 Pilot's Operating Handbook, Pilatus Report No. 01973-001, Temporary Revision, Fuel Filler Cap, dated March 27, 1998.''

Accomplishment of the replacement is required in accordance with Pilatus Service Bulletin No. 28-003, Revision 1, dated September 30, 1997. Accomplishment of the drilling and POH insertion is required in accordance with Pilatus Service Bulletin No. 28-004, dated March 27, 1998.

AD 98-11-01 was the result of a report of an incident where the inward vent valve of the fuel tank froze closed on one of the affected airplanes that was in compliance with the fuel tank vent valves replacement requirement of AD 97-23-04. This resulted in permanent structural damage to the wing skins and ribs.

This condition, if not corrected, could result in wing airfoil distortion and structural damage with consequent degradation of the airplane's handling qualities.

Relevant Service Information

Pilatus has issued Service Bulletin No. 28-005, dated May 4, 1998, which specifies procedures for modifying the fuel tank vent valves. This modification, when incorporated, would eliminate the need for the drilling and POH requirements of AD 98-11-01.

The FOCA of Switzerland classified this service bulletin as mandatory and issued Swiss AD HB 98-126, dated May 15, 1998, in order to assure the continued airworthiness of these airplanes in Switzerland.

The FAA's Determination

This airplane model is manufactured in Switzerland and is type certificated for operation in the United States under the provisions of Sec. 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the FOCA of Switzerland has kept the FAA informed of the situation described above.

The FAA has examined the findings of the FOCA of Switzerland; reviewed all available information, including the referenced service information; and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Explanation of the Provisions of This AD

Since an unsafe condition has been identified that is likely to exist or develop in other Models PC-12 and PC-12/45 airplanes of the same type design registered in the United States, the FAA

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is issuing an AD to revise AD 98-11-01. This AD:

--Maintains the requirements in AD 98-11-01 of replacing the fuel tank vent valves, drilling a 4.8 millimeter (0.1875 inch) hole in each fuel filler cap, and inserting a temporary revision in the POH that specifies checking to assure that the fuel filler cap hole is clear of ice and foreign objects; and --Adds the option of modifying the fuel tank vent valves instead of the drilling and POH requirements carried over from AD 98-11-01.

Accomplishment of the actions specified in this AD would be required in accordance with the following:

--Replacement: Pilatus Service Bulletin No. 28-003, Revision 1, dated September 30, 1997; --Drilling: Pilatus Service Bulletin No. 28-004, dated March 27, 1998; and --Modification: Pilatus Service Bulletin No. 28-005, dated May 4, 1998.

Cost Impact

The FAA estimates that 100 airplanes in the U.S. registry will be affected by this AD. The only difference between this AD and AD 98-11- 01 is the provision of accomplishing the modification instead of the drilling and POH insertion requirements carried over from AD 98-11-01. This replacement takes approximately 8 workhours per airplane to accomplish at an average labor rate of approximately $60 per work hour. Parts will be provided at no cost to the owner/operator of the affected airplanes. Based on these figures, the cost impact of this AD on U.S. operators that choose to incorporate the modification option instead of the drilling and POH requirements carried over from AD 98-11-01 is estimated to be $48,000, or $480 per airplane.

The Direct Final Rule Procedure

The FAA anticipates that this regulation will not result in adverse or negative comment and therefore is issuing it as a direct final rule. The requirements of this direct final rule address an unsafe condition identified by a foreign civil airworthiness authority and do not impose a significant burden on affected operators. In accordance with Sec. 11.17 of the Federal Aviation Regulations (14 CFR 11.17) unless a written adverse or negative comment, or a written notice of intent to submit an adverse or negative comment, is received within the comment period, the regulation will become effective on the date specified above. After the close of the comment period, the FAA will publish a document in the Federal Register indicating that no adverse or negative comments were received and confirming the date on which the final rule will become effective. If the FAA does receive, within the comment period, a written adverse or negative comment, or written notice of intent to submit such a comment, a document withdrawing the direct final rule will be published in the Federal Register, and a notice of proposed rulemaking may be published with a new comment period.

Comments Invited

Although this action is in the form of a final rule and was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified under the caption ADDRESSES. All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filedin the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: ``Comments to Docket No. 98-CE-40-AD.'' The postcard will be date stamped and returned to the commenter.

Regulatory Impact

The regulations adopted herein will not have substantial direct effects 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. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

The FAA has determined that this regulation is noncontroversial and unlikely to result in adverse or negative comments. For reasons discussed in the preamble, I certify that this regulation (1) is not a ``significant regulatory action'' under Executive Order 12866; (2) is not a ``significant rule'' under 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. A final evaluation has been prepared for this action and is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.

Adoption of the Amendment

Accordingly, pursuant to 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

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. Section 39.13 is amended by removing Airworthiness Directive (AD) 98-11-01, Amendment 39-10528 (63 FR 27195, May 18, 1998), and by adding a new AD to read as follows:

   98-11-01 R1 Pilatus Aircraft, LTD.: Amendment 39-10608; Docket No. 98-CE-40-AD; Revises AD 98-11-01, Amendment 39-10528.

   Applicability: Models PC-12 and PC-12/45 airplanes; serial numbers 101 through 230, certificated in any category.

   Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (f) of this AD. The request should include an assessment of the

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   effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

   Compliance: Required as indicated in the body of this AD, unless already accomplished.

   To prevent moisture from entering the fuel tank inward vent valve and then freezing after a cold soak at altitude, which could result in wing airfoil distortion and structural damage with consequent degradation of the airplane's handling qualities, accomplish the following:

   (a) Within the next 10 hours time-in-service (TIS) after December 1, 1997 (the effective date of AD 97-23-04), replace the fuel tank vent valves with modified fuel tank vent valves in accordance with the Accomplishment Instructions section of Pilatus Service Bulletin No. 28-003, Revision 1, dated September 30, 1997.

   (b) Within the next 10 hours TIS after June 7, 1998 (the effective date of AD 98-11-01), accomplish the following:

   (1) Drill a 4.8 millimeter (0.1875 inch) hole in each fuel filler cap in accordance with the Accomplishment Instructions section of Pilatus Service Bulletin No. 28-004, dated March 27, 1998.

   (2) Insert a temporary revision (as referenced in Pilatus Service Bulletin 28-004, dated March 27, 1998) into the Pilot's Operating Handbook (POH) that specifies checking to assure that the fuel filler cap hole is clear of ice and foreign objects. This document is entitled ``PC-12 Pilot's Operating Handbook, Pilatus Report No. 01973-001, Temporary Revision, Fuel Filler Cap, dated March 27, 1998.''

   (c) Inserting the POH revision, as required by paragraph (b)(2) of this AD, may be performed by the owner/operator holding at least a private pilot certificate as authorized by section 43.7 of the Federal Aviation Regulations (14 CFR 43.7), and must be entered into the aircraft records showing compliance with this AD in accordance with section 43.9 of the Federal Aviation Regulations (14 CFR 43.9).

   (d) As an alternative method of compliance to the actions required in paragraphs (b)(1) and (b)(2) of this AD, modify the fuel tank vent valve system in accordance with the Accomplishment Instructions section of Pilatus Service Bulletin No. 28-005, dated May 4, 1998.

   (e) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

   (f) An alternative method of compliance or adjustment of the compliance time that provides an equivalent level of safety may be approved by the Manager, Small Airplane Directorate, FAA, 1201 Walnut, suite 900, Kansas City, Missouri 64106.

   (1) The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Small Airplane Directorate.

   (2) Alternative methods of compliance approved in accordance with AD 98-11-01 (superseded by this action) and with AD 97-23-04 (superseded by AD 98-11-01) are considered approved as alternative methods of compliance for this AD.

   Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Small Airplane Directorate.

   (g) Questions or technical information to the service information referenced in this document should be directed to Pilatus Aircraft Ltd., CH-6370 Stans, Switzerland. This service information may be examined at the FAA, Central Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

   (h) The replacement required by this AD shall be done in accordance with Pilatus Service Bulletin No. 28-003, Revision 1, dated September 30, 1997. The drilling required by this AD shall be done in accordance with Pilatus Service Bulletin No. 28-004, dated March 27, 1998. The modification required by this AD shall be done in accordance with Pilatus Service Bulletin No. 28-005, dated May 4, 1998.

   (1) The incorporation by reference of Pilatus Service Bulletin No. 28-003, Revision 1, dated September 30, 1997, was previously approved by the Director of the Federal Register as of December 1, 1997 (62 FR 59993, November 6, 1997).

   (2) The incorporation by reference of Pilatus Service Bulletin No. 28-004, dated March 27, 1998, was approved by the Director of the Federal Register as of June 7, 1998 (63 FR 27195, May 18, 1998).

   (3) The incorporation by reference of Pilatus Service Bulletin No. 28-005, dated May 4, 1998, is approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.

   (4) Copies of these service bulletins may be obtained from Pilatus Aircraft Ltd., CH-6370 Stans, Switzerland. Copies may be inspected at the FAA, Central Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC.

   Note 3: The subject of this AD is addressed in Swiss AD HB 97- 432A, dated October 3, 1997; Swiss AD HB 98-086, dated March 31, 1998; and Swiss AD HB 98-126, dated May 15, 1998.

   (i) This amendment revises AD 98-11-01, Amendment 39-10528; which superseded AD 97-23-04, Amendment No. 39-10192.

   (j) This amendment becomes effective on September 22, 1998.

   Issued in Kansas City, Missouri, on June 11, 1998. Ronald K. Rathgeber, Acting Manager, Small Airplane Directorate, Aircraft Certification Service.

   [FR Doc. 98-16163Filed6-24-98; 8:45 am]

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