Airworthiness Directives; Various Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Supplemental notice of proposed rulemaking (SNPRM).

SUMMARY:

The FAA is revising a notice of proposed rulemaking (NPRM) that applied to various airplanes modified with a certain configuration of the Garmin GFC 500 Autopilot System installed per Supplemental Type Certificate (STC) No. SA01866WI. This action revises the NPRM by removing airplane models from and adding airplane models to the applicability. The FAA is proposing this airworthiness directive to address the unsafe condition on these products. Since this action would expand the applicability for the required action as proposed in the NPRM, the agency is requesting comments on this SNPRM.

DATES:

The FAA must receive comments on this SNPRM by June 3, 2024.

ADDRESSES:

You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods:

• Federal eRulemaking Portal: Go to regulations.gov. Follow the instructions for submitting comments.

• Fax: (202) 493-2251.

• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.

• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2023-1990; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this SNPRM, any comments received, and other information. The street address for Docket Operations is listed above.

FOR FURTHER INFORMATION CONTACT:

Christopher Withers, Aviation Safety Engineer, FAA, 1801 S Airport Road, Wichita, KS 67209; phone: (316) 946-4190; email: christopher.d.withers@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2023-1990; Project Identifier AD-2023-00734-A” at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may again revise this proposal because of those comments.

Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this proposed AD.

Confidential Business Information

CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this SNPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this SNPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this SNPRM. Submissions containing CBI should be sent to Christopher Withers, Aviation Safety Engineer, FAA, 1801 S Airport Road, Wichita, KS 67209. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking.

Background

The FAA issued an NPRM to amend 14 CFR part 39 by adding an AD that would apply to various airplanes modified with a certain configuration of the Garmin GFC 500 Autopilot System installed per STC No. SA01866WI. The NPRM published in the Federal Register on October 10, 2023 (88 FR 69891). The NPRM was prompted by a report of an un-commanded automatic pitch trim runaway when the autopilot was first engaged. In the NPRM, the FAA proposed to require updating the applicable Garmin GFC 500 Autopilot System software for your airplane and prohibit installing earlier versions of that software.

Actions Since the NPRM Was Issued

Based on the comments the FAA received on the NPRM, the FAA is proposing revising the applicability by removing and adding airplane models, revising paragraph (e) of the proposed AD to clarify that certain hardware failures affected the primary pitch servo, and adding Note 1 to paragraph (g) of the proposed AD.

Comments

The FAA received comments from several individuals and the National Transportation Safety Board (NTSB), who supported the NPRM without change.

The FAA also received three comments from Garmin. The following presents the comments received on the NPRM and the FAA's response to each comment.

Request To Correct Language in Paragraph (e) of the Proposed AD

Garmin stated that paragraph (e) of the proposed AD incorrectly states that hardware faults can occur in the pitch trim servo. Garmin explained that hardware faults occur in the pitch servo, not the pitch trim servo. Garmin requested a correction to state that hardware faults occur in the pitch servo.

The FAA agrees with the commenter. The FAA has corrected paragraph (e) of the proposed AD to change the wording from “pitch trim servo” to “primary pitch servo.”

Request To Reference Service Information

Garmin also stated that paragraph (g) of the proposed AD should reference Garmin Mandatory STC Service Bulletin (SB) 22123, Rev A, dated January 3, 2023, or later revision, because it would help operators find the easiest path to compliance.

The FAA partially agrees. The FAA agrees that referencing the SB will help operators find a path to compliance but disagrees that operators should be required to use the SB to update the software. The SB requires performing multiple actions, whereas the specified action in this proposed AD is to only update the software version. The FAA has added Note 1 to paragraph (g) of this proposed AD to inform operators that the software update can be done using Garmin Mandatory STC Service Bulletin 22123, Rev A, dated January 3, 2023.

Request To Add Additional Airplane Models

Garmin further stated that the proposed AD would affect more airplane models than what are included in paragraph (c) of the proposed AD. The FAA infers that Garmin requested the applicability of the NPRM be revised to include additional airplane models.

The FAA agrees and has updated paragraph (c) of this proposed AD to include additional affected airplane models.

Additional Change Made to the Applicability

Since the NPRM published, the FAA determined the need to remove Commander Aircraft Corporation Model 112 airplanes and Textron Aviation Inc. Model 177 airplanes from paragraph (c), Applicability, of this proposed AD. Paragraph (c) of the proposed AD specifies that the affected airplanes are those having a Garmin GFC 500 Autopilot System that includes an optional GSA 28 pitch trim servo installed per STC No. SA01866WI using Master Drawing List (MDL) 005-01264-00, Revisions 1 through 76. The software change to eliminate the unsafe condition identified in this proposed AD was included in MDL revision 77 so airplanes incorporating this STC using MDL revision 77 and higher do not have the software that exhibits the unsafe condition. When installing STC No. SA01866WI, operators of Model 112 airplanes are using MDL revision 78 and operators of Model 177 airplanes are using MDL revision 83, therefore they should not be included in the applicability.

The FAA also determind the need to remove Textron Aviation Inc. Model 182 airplanes from paragraph (c) of this proposed AD. Although Model 182 airplanes are using MDL revision 61, they are not affected by the identified unsafe condition because the mechanical characteristics prohibit the installation of a pitch trim servo.

The FAA further determined the need to remove Mooney International Corporation Model M20 airplanes and Textron Aviation Inc. Model 172, 206, and 210 airplanes from paragraph (c) of this proposed AD. These airplane models are not listed in the FAA Approved Model List (AML), amended September 8, 2023, for STC No. SA01866WI.

FAA's Determination

The FAA is proposing this AD after determining the unsafe condition described previously is likely to exist or develop in other products of the same type design. Certain changes described above expand the scope of the NPRM. As a result, it is necessary to reopen the comment period to provide additional opportunity for the public to comment on this SNPRM.

Proposed AD Requirements in This SNPRM

This proposed AD would require updating the applicable Garmin GFC 500 Autopilot System software for your airplane and would prohibit installing earlier versions of that software.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would affect 5,900 airplanes of U.S. registry.

The FAA estimates the following costs to comply with this proposed AD:

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.

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.

Regulatory Findings

The FAA 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) Would not affect intrastate aviation in Alaska, and

(3) Would not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• 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.

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

Various Airplanes: Docket No. FAA-2023-1990; Project Identifier AD-2023-00734-A.

(a) Comments Due Date

The FAA must receive comments on this airworthiness directive (AD) by June 3, 2024.

(b) Affected ADs

None.

(c) Applicability

This AD applies to all airplane models specified in Table 1 to paragraph (c) of this AD, certificated in any category, having a Garmin GFC 500 Autopilot System that includes an optional GSA 28 pitch trim servo installed per Supplemental Type Certificate No. SA01866WI using Master Drawing List 005-01264-00, Revisions 1 through 76.

(d) Subject

Joint Aircraft System Component (JASC) Code 2210, Autopilot System.

(e) Unsafe Condition

This AD was prompted by a report of an un-commanded automatic pitch trim runaway when the autopilot was first engaged. The FAA is issuing this AD to address autopilot software that does not properly handle certain hardware failures of the primary pitch servo. The unsafe condition, if not addressed, could result in un-commanded automatic pitch trim runaway and loss of control of the airplane.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Required Action

Within 12 months after the effective date of this AD, update the Garmin GFC 500 Autopilot System software applicable to your airplane to a version that is not 8.01 or earlier for the G5, not version 9.01 or earlier for the G3X Touch, and not version 2.59 or earlier for the GI 275.

Note 1 to paragraph (g):

The software update can be done using Garmin Mandatory STC Service Bulletin 22123, Rev A, dated January 3, 2023. This AD also allows the installation of versions other than those listed in Garmin Mandatory STC Service Bulletin 22123, Rev A, dated January 3, 2023, provided those versions are not listed in paragraph (g) of this AD.

(h) Installation Prohibition

As of the effective date of this AD, do not install Garmin GFC 500 Autopilot System Software that is version 8.01 or earlier for the G5, version 9.01 or earlier for the G3X Touch, or version 2.59 or earlier for the GI 275, on any airplane.

(i) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Central Certification Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the Central Certification Branch, send it to the attention of the person identified in paragraph (j)(1) of this AD. Information may be emailed to wichita-cos@faa.gov.

(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.

(j) Related Information

(1) For more information about this AD, contact Christopher Withers, Aviation Safety Engineer, FAA, 1801 S Airport Road, Wichita, KS 67209; phone: (316) 946-4190; email: christopher.d.withers@faa.gov.

(2) For service information identified in this AD that is not incorporated by reference, contact Garmin International, Attention: Garmin Aviation Support, 1200 E. 151st Street, Olathe, KS 66062; phone: (866) 739-5687; website: support.garmin.com/en-US/aviation/.

(k) Material Incorporated by Reference

None.