00-7335. Airworthiness Directives; Learjet Model 35, 35A, 36, 36A, 55, 55B, and 55C Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Final rule; rescission.

SUMMARY:

This amendment rescinds an existing Airworthiness Directive (AD), applicable to certain Learjet Model 35, 35A, 36, 36A, 55, 55B, and 55C airplanes. That AD currently requires installation of a placard on the instrument panel in the cockpit to advise the flightcrew that the Omega navigation system may be inoperative at certain engine speeds. That AD also provides for an optional installation of certain band reject filters, which eliminates the need for the placard. The requirements of that AD were intended to prevent excessive deviation from the intended flight path due to loss of navigation signals, which could result in a potentially low-fuel condition or a traffic conflict. Since the issuance of that AD, use of the Omega navigation system has been permanently discontinued; therefore, the original unsafe condition no longer exists.

EFFECTIVE DATE:

March 27, 2000.

FOR FURTHER INFORMATION CONTACT:

C. Dale Bleakney, Aerospace Engineer, Flight Test Branch, ACE-117W, FAA, Small Airplane Directorate, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

On September 5, 1995, the Federal Aviation Administration (FAA) issued AD 95-19-04, amendment 39-9365 (60 FR 47265, September 12, 1995), applicable to certain Learjet Model 35, 35A, 36, 36A, 55, 55B, and 55C airplanes. That AD requires installation of a placard on the instrument panel in the cockpit to advise the flightcrew that the Omega navigation system may be inoperative at certain engine speeds. That AD also provides for an optional installation of certain band reject filters, which eliminates the need for the placard. That action was prompted by reports of loss of certain navigation signals during extended over-water operation. That condition, if not corrected, could result in excessive deviation from the intended flight path due to loss of navigation signals, and consequent potential low-fuel condition or a traffic conflict.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received in response to the proposal.

Conclusion

After careful review of the available data, the FAA has determined that air safety and the public interest require the rescission of the rule as proposed.

Regulatory Impact

The regulations adopted herein 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. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this action: (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 it 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
• Safety

The Rescission

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.

§ 39.13

[Amended]

2. Section 39.13 is amended by adding an airworthiness directive removing amendment 39-9365 to read as follows:

95-19-04 R1 Learjet: Amendment 39-11649. Docket No. 99-NM-311-AD. Rescinds AD 95-19-04, Amendment 39-9365.

Applicability: Model 35, 35A, 36, 36A, 55, 55B, and 55C airplanes; equipped with Global Wulfsburg GNS 500, GNS-1000, and GNS-X Flight Management Systems; certificated in any category.

This rescission is effective March 27, 2000.

Issued in Renton, Washington, on March 20, 2000.

Donald L. Riggin,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.