Airworthiness Directives; GARMIN International Inc. GTX 330 Mode S Transponders and GTX 330D Diversity Mode S Transponders

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

The FAA adopts a new airworthiness directive (AD) for certain GARMIN International Inc. GTX 330/GTX 330D Mode S transponders that are installed on aircraft. This AD requires you to install GTX 330/330D Software Upgrade Version 3.03, 3.04, or 3.05. This AD is the result of observations that the GTX 330 and GTX 330D may detect, from other aircraft, the S1 (suppression) interrogating pulse below the Minimum Trigger Level (MTL) and, in some circumstances, not reply. The GTX 330/330D should still reply even if it detects S1 interrogating pulses below the MTL. We are issuing this AD to prevent interrogating aircraft from possibly receiving inaccurate replies due to suppression from aircraft equipped with the GTX 330/330D Mode S Transponders when the pulses are below the MTL. The inaccurrate replies could result in reduced vertical separation or unsafe TCAS resolution advisories.

DATES:

This AD becomes effective on July 9, 2004.

As of July 9, 2004, the Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulation.

ADDRESSES:

You may get the service information identified in this AD from GARMIN International Inc., 1200 East 151st Street, Olathe, KS 66062, (913) 397-8200.

You may view the AD docket at FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2003-CE-39-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:

Roger A. Souter, FAA, Wichita Aircraft Certification Office (ACO), 1801 Airport Road, Room 100, Wichita, Kansas 67209; telephone: 316-946-4134; facsimile: 316-946-4107; e-mail address: roger.souter@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

What events have caused this AD? The GTX 330/GTX 330D may detect from other aircraft the S1 (suppression) interrogating pulse below the MTL and, in some circumstances, does not reply. The GTX 330/330D should still reply even if it detects S1 interrogating pulses below the MTL. GARMIN International Inc. suspected the suppression problem after observation between GARMIN company aircraft that were equipped with the GTX 330 and Ryan Traffic and Collision Alert Device (TCAD). Engineering bench tests and test flights confirmed that this suppression problem existed.

What is the potential impact if FAA took no action? Interrogating aircraft could possibly receive inaccurate replies due to suppression from aircraft equipped with the GTX 330/330D Mode S Transponders when the pulses are below the MTL. The inaccurate replies could result in reduced vertical separation or unsafe TCAS resolution advisories.

Has FAA taken any action to this point? We issued a proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to certain GARMIN International Inc. GTX 330/330D Mode S transponders that are installed on aircraft. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on December 30, 2003 (68 FR 75174). The NPRM proposed to require you to install GTX 330/330D Software Upgrade Version 3.03.

Comments

Was the public invited to comment? We provided the public the opportunity to participate in developing this AD. The following presents the comments received on the proposal and FAA's response to each comment:

Comment Issue: GTX 330/330D Software Upgrade Version 3.03

What is the commenter's concern? The NPRM currently requires installation of GTX 330/330D Software Upgrade to Version 3.03 to comply with the proposed AD. Two commenters request a text change of the AD to allow installation of later software upgrade versions to comply with the proposed AD.

What is FAA's response to the concern? Since later software upgrade versions will contain, at a minimum, the elements of Version 3.03 and thus will correct the unsafe condition, we agree with their request and have changed the text from “Version 3.03” to “Version 3.03, 3.04, or 3.05.”

Conclusion

What is FAA's final determination on this issue? We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed except for the changes discussed above and minor editorial corrections. We have determined that these changes and minor corrections:

—Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and

—Do not add any additional burden upon the public than was already proposed in the NPRM.

Changes to 14 CFR Part 39—Effect on the AD

How does the revision to 14 CFR part 39 affect this AD? On July 10, 2002, the FAA published a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs the 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.

Cost of Compliance

How many airplanes does this AD impact? We estimate that this AD affects 1,300 airplanes in the U.S. registry.

What is the cost impact of this AD on owners/operators of the affected airplanes? Garmin International Inc. will reimburse the 1.0 hours required for this modification per the most current GTX 330 Software Service Bulletin. This reimbursement will follow Garmin's warranty Policies and Procedures stating that the most current software, which includes this update and all other updates, should be installed.

Compliance Time of This AD

What will be the compliance time of this AD? The compliance time of this AD is within 30 days after the effective date of the AD.

Why is the compliance time presented in calendar time instead of hours time-in-service (TIS)? The unsafe condition exists or could develop on airplanes equipped with the affected equipment regardless of airplane operation. For example, the unsafe condition has the same chance of occurring on an airplane with 50 hours TIS as it does on one with 5,000 hours TIS. Therefore, we are presenting the compliance time of this AD in calendar time instead of hours TIS.

Regulatory Findings

Will this AD impact various entities? We have 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.

Will this AD involve a significant rule or regulatory action? For the reasons discussed above, I certify that this 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 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-39-AD” in your request.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

Accordingly, under 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.

2. FAA amends § 39.13 by adding a new AD to read as follows:

2004-10-15 Garmin International Inc.: Amendment 39-13645; Docket No. 2003-CE-39-AD.

When Does This AD Become Effective?

(a) This AD becomes effective on July 9, 2004.

What Other ADs Are Affected by This Action?

(b) None.

What Airplanes Are Affected by This AD?

(c) This AD affects GARMIN International Inc. GTX 330/330D Mode S transponders that are installed on, but not limited to, the following airplanes, certificated in any category:

What Is the Unsafe Condition Presented in This AD?

(d) The actions specified in this AD are intended to prevent interrogating aircraft from possibly receiving inaccurate replies, due to suppression, from aircraft equipped with the GTX 330/330D Mode S Transponders when the pulses are below the Minimum Trigger Level (MTL). The inaccurate replies could result in vertical separation or unsafe TCAS resolution advisories.

What Must I Do To Address This Problem?

(e) To address this problem, you must do the following:

May I Request an Alternative Method of Compliance?

(f) You may request a different method of compliance or a different compliance time for this AD by following the procedures in 14 CFR 39.19. Unless FAA authorizes otherwise, send your request to your principal inspector. The principal inspector may add comments and will send your request to the Manager, Wichita Aircraft Certification Office (ACO), FAA. For information on an already approved alternative methods of compliance, contact Roger A. Souter, FAA, Witchita ACO, 1801 Airport Road, Room 100, Wichita, Kansas 67209; telephone: 316-946-4134; facsimile: 316-946-4107; e-mail address: roger.souter@faa.gov.

Does This AD Incorporate Any Material by Reference?

(g) You must do the actions required by this AD following the instructions in GARMIN Mandatory Software Service Bulletin No.: 0304, Rev B, dated June 12, 2003 (SW Version 3.03); Garmin Software Service Bulletin No. 0310, Rev A, dated November 10, 2003 (SW Version 3.04); or Garmin Software Service Bulletin No. 0401, Rev A, dated February 18, 2004 (SW Version 3.05). The Director of the Federal Register approved the incorporation by reference of this service bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may get a copy from GARMIN International Inc. 1200 East 151st Street, Olathe, KS 66062. You may review copies at FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.