# AD 95-19-04 R1 RES: Omega Navigation System - Type: Airworthiness directive - Status: Current - Products: Learjet 35, 35A (C-21A), 36, 36A, 55, 55B and 55C - Effective: March 27, 2000 - Published: March 27, 2000, 65 FR 16129–16130 - Issued: March 20, 2000 - Issued as: Final rule; rescission - Supersedes: [AD 95-19-04](https://openairdocs.org/ad/95-19-04) - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Small/large airplane - Amendment: 39-11649 - Docket: 99-NM-311-AD - Registered aircraft: 278 may be affected, by airframe or engine model (OpenAirDocs) - Official PDF: https://openairdocs.org/files/sha256/70/0c/700cb83f9d4fff874521c710d7c03aeb05e665a8871ee94bf22c012c2abc80ba (from https://www.govinfo.gov/content/pkg/FR-2000-03-27/pdf/00-7335.pdf) - Federal Register: https://www.federalregister.gov/documents/2000/03/27/00-7335/airworthiness-directives-learjet-model-35-35a-36-36a-55-55b-and-55c-airplanes - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/C850BF0595AD442B86256A4C005E75E3.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/95-19-04-R1-RES ## 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. ## The airworthiness directive ### 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: 1. The authority citation for part 39 continues to read as follows: 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. ## Rule preamble ### 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 (316) 946-4135; fax (316) 946-4407. ### 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. ## Affected data sheets (1) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS A10CE](https://openairdocs.org/tcds/A10CE): Learjet Inc.; names 7 of 29 models: 35, 35A (C-21A), 36, 36A, 55, 55B, 55C ## Registered aircraft it may apply to (OpenAirDocs) Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment. - Aircraft: 278 (278 by airframe model, 0 by engine model) - Makers: Gates Learjet 199, Gates Lear Jet 50, Learjet 29 Models with the most aircraft: - [Gates Learjet 35A](https://openairdocs.org/model/gates-learjet-35a): 135 aircraft (airframe model) - [Gates Learjet 55](https://openairdocs.org/model/gates-learjet-55): 54 aircraft (airframe model) - [Learjet 35A](https://openairdocs.org/model/learjet-35a): 24 aircraft (airframe model) - [Gates Lear Jet 36A](https://openairdocs.org/model/gates-lear-jet-36a): 21 aircraft (airframe model) - [Gates Lear Jet 35](https://openairdocs.org/model/gates-lear-jet-35): 16 aircraft (airframe model) - [Gates Lear Jet 36](https://openairdocs.org/model/gates-lear-jet-36): 13 aircraft (airframe model) - [Gates Learjet 55C](https://openairdocs.org/model/gates-learjet-55c): 6 aircraft (airframe model) - [Learjet 55](https://openairdocs.org/model/learjet-55): 4 aircraft (airframe model) - [Gates Learjet 55B](https://openairdocs.org/model/gates-learjet-55b): 3 aircraft (airframe model) - [Learjet 35](https://openairdocs.org/model/learjet-35): 1 aircraft (airframe model) - [Gates Learjet 35A (C-21A)](https://openairdocs.org/model/gates-learjet-35a-c-21a): 1 aircraft (airframe model) All 12 models: https://openairdocs.org/ad/95-19-04-R1-RES/models.md Every aircraft: https://openairdocs.org/ad/95-19-04-R1-RES/aircraft.md ## Related documents - [AD 95-19-04](https://openairdocs.org/ad/95-19-04) (historical): Omega Navigation System · Learjet 35, 35A (C-21A), 36 and 4 more. Effective Oct 12, 1995. Replaced by this AD - [Proposed rule 99-NM-311-AD](https://openairdocs.org/proposed/99-NM-311-AD): Notice of proposed rulemaking (NPRM); rescission, published Dec 29, 1999 Its text cites no advisory circulars or STCs. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.