AD 2022-19-03

This AD is effective October 27, 2022.

The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of October 27, 2022.

For service information identified in this final rule, contact Pilatus Aircraft Ltd., CH-6371, Stans, Switzerland; phone: +41848247365; email: techsupport.ch@pilatus-aircraft.com; website: pilatus-aircraft.com/. You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 901 Locust, Kansas City, MO 64106. For information on the availability of this material at the FAA, call (817) 222-5110. It is also available at regulations.gov by searching for and locating Docket No. FAA-2022-0153.

Doug Rudolph, Aviation Safety Engineer, General Aviation & Rotorcraft Section, International Validation Branch, 901 Locust, Room 301, Kansas City, MO 64106; phone: (816) 329-4059; email: doug.rudolph@faa.gov.

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2016-26-08, Amendment 39-18766 (82 FR 1172, January 5, 2017; corrected February 16, 2017, 82 FR 10859) (AD 2016-26-08). AD 2016-26-08 applied to all Pilatus Aircraft Ltd. (Pilatus) Model PC-12, PC-12/45, PC-12/47, and PC-12/47E airplanes. AD 2016-26-08 required incorporating revisions into the ALS of the existing FAA-approved maintenance program and inspecting the MLG attachment bolts for cracks and corrosion.

The NPRM published in the Federal Register on March 14, 2022 (87 FR 14187). The NPRM was prompted by reports of failure of MLG actuator bottom attachment bolts, part number 532.10.12.218, identified with “VLG” on the bolt head. These parts are from a specific vendor and are subject to hydrogen embrittlement. Accordingly, EASA, which is the Technical Agent for the Member States of the European Union, superseded its prior AD on this condition and issued EASA AD 2021-0005, dated January 7, 2021, corrected January 14, 2021, to require a new 5-year life limit for the MLG actuator bottom attachment bolt identified with “VLG.” Pilatus subsequently added new life limits for the rudder bellcrank. As a result, EASA superseded its AD again and issued AD 2021-0214, dated September 17, 2021 (referred to after this as “the MCAI”). The MCAI states:

The airworthiness limitations and certification maintenance instructions for Pilatus PC-12 aeroplanes, which are approved by EASA, are currently defined and published in Pilatus PC-12 AMM Chapter 04-00-00. These instructions have been identified as mandatory for continued airworthiness.

Failure to accomplish these instructions could result in an unsafe condition.

Previously, EASA issued [EASA] AD 2021-0005, requiring the actions described in the Pilatus PC-12 AMM Chapter 04-00-00, Document Number 02049 Issue 01 Revision 40, Document Number 02300 Issue 01 Revision 24 and Document Number 02436 Issue 01 Revision 02.

Since that [EASA] AD was issued, Pilatus published the applicable ALS, as defined in this [EASA] AD, which contains new and/or more restrictive tasks and limitations, as specified in the Component Limitations section, to introduce a new life limit for the rudder bellcrank. Due to the introduction of this life limit, the repetitive eddy current inspections are no longer required and deleted from the Supplemental Structural Inspection section.

For the reason described above, this [EASA] AD retains the requirements of EASA AD 2021-0005, which is superseded, and requires accomplishment of the actions as specified in the applicable ALS.

You may examine the MCAI at regulations.gov by searching for and locating Docket No. FAA-2022-0153.

In the NPRM, the FAA proposed to require incorporating new revisions to the ALS of the existing AMM or ICA to establish a 5-year life limit for certain MLG actuator bottom attachment bolts and new life limits for the rudder bellcrank. The FAA is issuing this AD to prevent MLG collapse during all phases of airplane operations, including take-off and landing, and also to prevent rudder bellcrank failure, which could lead to loss of airplane control.

The FAA received comments from four commenters. The commenters were the Air Line Pilots Association (ALPA), Pilatus, and two individuals. The following presents the comments received on the NPRM and the FAA's response to each comment.

ALPA supported the NPRM without change.

Pilatus requested that the FAA change the proposed AD to reference the most recent AMM revisions, which were issued December 10, 2021. Pilatus stated that it updated the AMM, including the ALS, for editorial changes and that requiring incorporation of the later AMM revisions would not increase the public burden. An individual commenter requested the FAA change the proposed AD to allow operators to comply by incorporating later FAA-approved revisions of the ALS. The commenter stated that not including this statement restricts operators to using the ALS revision required by the AD, unless they obtain approval of an alternative method of compliance (AMOC).

The FAA partially agrees. The FAA agrees to allow incorporation of the latest revisions of the ALS, as requested by Pilatus, as an option for compliance with paragraph (f)(1) of this AD, and has updated this final rule accordingly. The FAA does not agree with allowing future revisions of the ALS as an option for compliance with paragraph (f)(1) of this AD. An AD may not refer to a document that does not exist at the time the AD is published. The Office of the Federal Register (OFR) regulations for approval of materials “incorporated by reference” in rules require that service documents be submitted to the OFR for approval as “referenced material.” An AD may reference only the specific service document that was submitted and approved by the OFR for incorporation by reference. The individual commenter is correct that in order for operators to use later revisions of the referenced document (issued after the publication of the AD), either the FAA must revise the AD to reference the specific later revisions, or operators must request the approval of their use as an AMOC.

An individual commenter requested the FAA adjust the average labor rate to reflect the current economic burden. The individual stated that the average labor rate in the NPRM is too low.

The FAA disagrees. The FAA Office of Aviation Policy and Plans provides the labor rate of $85 per work-hour for the FAA to use when estimating the labor costs of complying with AD requirements. The FAA did not change this final rule based on this comment.

The FAA has revised the document citations for the service information required in this AD to adhere to OFR regulations for materials incorporated by reference.

These products have been approved by the aviation authority of another country and are approved for operation in the United States. Pursuant to the FAA's bilateral agreement with this State of Design Authority, it has notified the FAA of the unsafe condition described in the MCAI referenced above. The FAA reviewed the relevant data, considered the comments received, and determined that air safety requires adopting this AD as proposed. Accordingly, the FAA is issuing this AD to address the unsafe condition on these products. Except for the changes described previously, this AD is adopted as proposed in the NPRM. None of the changes will increase the economic burden on any operator.

The FAA reviewed the following service information, which contains the new life limit for certain MLG actuator bottom attachment bolts and new life limits for the rudder bellcrank. These documents are distinct because they apply to different airplane models; the different revision levels include editorial updates.

• PC-12, PC-12/45, PC-12/47 Structural, Component and Miscellaneous Limitations—AMM Document No. 02049—Airworthiness Limitations, Document Module Code 12-A-04-00-00-00A-000A-A, of the Pilatus Model type—PC-12, PC-12/45, PC-12/47 MSN-101-888 Aircraft Maintenance Manual Document No. 02049, Revision 41, dated July 16, 2021.

• PC-12, PC-12/45, PC-12/47 Structural, Component and Miscellaneous Limitations—AMM Document No. 02049—Airworthiness Limitations, Document Module Code 12-A-04-00-00-00A-000A-A, of the Pilatus Model type—PC-12, PC-12/45, PC-12/47 MSN-101-888 Aircraft Maintenance Manual Document No. 02049, Revision 42, dated December 10, 2021.

• PC-12/47E Structural, Component and Miscellaneous Limitations—AMM Document No. 2300—Airworthiness Limitations, Document Module Code 12-B-04-00-00-00A-000A-A, of the Pilatus Model type—PC-12/47E MSN-545/1001-1719 and 1721-1942 Aircraft Maintenance Manual Document No. 02300, Revision 25, dated July 16, 2021.

• PC-12/47E Structural, Component and Miscellaneous Limitations—AMM Document No. 2300—Airworthiness Limitations, Document Module Code 12-B-04-00-00-00A-000A-A, of the Pilatus Model type—PC-12/47E MSN-1001-1942 (except MSN 1720) Aircraft Maintenance Manual Document No. 02300, Revision 26, dated December 10, 2021.

• PC-12/47E Structural, Component and Miscellaneous Limitations—AMM Document No. 02436—Airworthiness Limitations, Document Module Code 12-C-04-00-00-00A-000A-A, of the Pilatus Model type—PC-12/47E MSN 1720, 2001-Up Aircraft Maintenance Manual Document No. 02436, Revision 03, dated July 16, 2021.

• PC-12/47E Structural, Component and Miscellaneous Limitations—AMM Document No. 02436—Airworthiness Limitations, Document Module Code 12-C-04-00-00-00A-000A-A, of the Pilatus Model type—PC-12/47E MSN 1720, 2001-Up Aircraft Maintenance Manual Document No. 02436, Revision 04, dated December 10, 2021.

This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

The FAA estimates that this AD affects 1,030 airplanes of U.S. registry. The FAA also estimates that it will take 1 work-hour per airplane to incorporate the revised ALS into the AMM or ICA. The average labor rate is $85 per work-hour. Based on these figures, the FAA estimates the cost on U.S. operators to be $87,550 or $85 per airplane.

In addition, the FAA estimates that replacing a MLG actuator bottom attachment bolt, if necessary, will take 1 work-hour and will require parts costing $2,140 for a cost of $2,225 per airplane.

Replacing the rudder bellcrank, if necessary, will take 3 work-hours and will require parts costing $550 for a cost of $805 per airplane.

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.

The FAA is 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.

The FAA has 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 that this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866,

(2) Will not affect intrastate aviation in Alaska, 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.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

1. The authority citation for part 39 continues to read as follows:

2. The FAA amends § 39.13 by:

a. Removing Airworthiness Directive 2016-26-08, Amendment 39-18766 (82 FR 1172, January 5, 2017; corrected February 16, 2017, 82 FR 10859); and

b. Adding the following new airworthiness directive: