AD Amdt-39-11649

final rule

Airworthiness Directives; Learjet Model 35, 35A, 36, 36A, 55, 55B, and 55C Airplanes

AD Number
Amdt-39-11649
Status
final_rule
Effective Date
Product Category
engine
Docket
Docket No. 99-NM-311-AD
FR Citation
65 FR 16129

Applicability

TypeManufacturerModelDetails
aircraft Learjet 35 Airworthiness Directives; Learjet Model 35, 35A, 36, 36A, 55, 55B, and 55C Airplanes

Unsafe Condition

Excessive deviation from the intended flight path due to loss of navigation signals from the Omega navigation system at certain engine speeds could result in a potentially low-fuel condition or a traffic conflict.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Rescind the existing AD requirements including the installation of a placard on the instrument panel and the optional installation of band reject filters.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before further flight

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Learjet Model 35, 35A, 36, 36A, 55, 55B, and 55C airplanes subject to the previous AD requiring Omega navigation system placarding or filter installation.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

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.

Document Text

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[Federal Register Volume 65, Number 59 (Monday, March 27, 2000)]
[Rules and Regulations]
[Pages 16129-16130]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 00-7335]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-311-AD; Amendment 39-11649; AD 95-19-04 R1]
RIN 2120-AA64


Airworthiness Directives; Learjet Model 35, 35A, 36, 36A, 55, 
55B, and 55C Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; rescission.

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[[Page 16130]]

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 (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.

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.


Sec. 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.
[FR Doc. 00-7335 Filed 3-24-00; 8:45 am]
BILLING CODE 4910-13-U

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