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FAA orders · airworthiness directive · historical

98-11-01: Fuel Tank Vent Valves

FAA order 98-11-01 is an airworthiness directive in force since June 7, 1998. The FAA's subject line: Fuel Tank Vent Valves. It names Pilatus PC-12: about 1,447 aircraft on the U.S. register today, though an order usually covers particular versions or serial numbers rather than every one. System: fuel system.

What it applies to as the FAA lists it

Kind of product
Aircraft
Makes
Pilatus Aircraft Limited; Pilatus Aircraft Limited; Pilatus Aircraft Limited; Pilatus Aircraft Limited; Pilatus Aircraft Limited; Pilatus Aircraft Limited; Pilatus Aircraft Limited
Models
PC-12, PC-12/45
On this site
Pilatus PC-12 1,447 registered

Dates and paperwork

In force since
June 7, 1998
Published
May 18, 1998
Docket
98-CE-40-AD
Replaces
97-23-04
Replaced by
98-11-01 R1
Status
Historical
The FAA's document
Read the order on the FAA's site

The FAA's summary their words, unchanged

This amendment supersedes Airworthiness Directive (AD) 97-23-04, which currently requires replacing the fuel tank vent valves with modified fuel tank vent valves on certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This AD retains 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 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 is the result of mandatory continued airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent the fuel tank inward vent valve from freezing, which, if followed by a cold soak at altitude, could result in wing airfoil distortion and structural damage with consequent degradation of the airplane's handling qualities.

The order itself the regulatory text, as published

Show the full text (5,460 characters)
98-11-01 PILATUS AIRCRAFT, LTD.: Amendment 39-10528; Docket No. 98-CE-40-AD; Supersedes AD 97-23-04, Amendment No. 39-10192. 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 (e) of this AD. The request should include an assessment of the 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 the fuel tank inward vent valve from freezing, which, if followed by a cold soak at altitude, 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 the effective date of this AD, 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) 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. (e) 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 97-23-04 (superseded by this action) 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. (f) Questions or technical information related to Pilatus Service Bulletin No. 28-004, dated March 27, 1998, 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. (g) 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. (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 in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. (3) 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, and Swiss AD HB 98-086, dated March 31, 1998. (h) This amendment supersedes AD 97-23-04, Amendment No. 39-10192. (i) This amendment becomes effective on June 7, 1998.

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Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of November 6, 2026. Connections as data: /graph/directive/98-11-01.json · aircraft systems.