AD 99-10-14

final rule

Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes

AD Number
99-10-14
Status
final_rule
Effective Date
Product Category
aircraft
Docket
98-NM-232-AD
FR Citation
(Federal Register: May 14, 1999 (Volume 64, Number 92))

Applicability

TypeManufacturerModelDetails
aircraft The Boeing Company 747-400 Series Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes
aircraft The Boeing Company 747-400D Series Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes
aircraft The Boeing Company 747-400F Series Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes
aircraft The Boeing Company 757-200 Series Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes
aircraft The Boeing Company 757-200CB Series Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes
aircraft The Boeing Company 757-200PF Series Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes
aircraft The Boeing Company 757-300 Series Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes
aircraft The Boeing Company 767-200 Series Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes
aircraft The Boeing Company 767-300 Series Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes
aircraft The Boeing Company 767-300F Series Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes
aircraft The Boeing Company 777-200 Series Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes
aircraft The Boeing Company 777-300 Series Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes

Unsafe Condition

Erroneous localizer deviation provided by faulty ILS receivers could result in a landing outside the lateral boundary of the runway.

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

Required Actions

Replace all existing RIA-35B ILS receivers (P/N 066-50006-0101) with modified units (P/N 066-50006-1101) per AlliedSignal Service Bulletin M-4426 within 6 months of AD effective date. Previously, inspections for fault codes 'Nl'/'Nm' were required every 64 flight cycles, with replacement of discrepant receivers. AFM revisions and placards prohibiting certain approaches were also mandated.

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

Compliance Time

Within 6 months after the effective date of this AD

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

Affected Aircraft

Boeing Model 747-400, 757, 767, and 777 series airplanes equipped with AlliedSignal RIA-35B ILS receivers, P/N 066-50006-0101.

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

Federal Register Abstract

Instrument Landing System

Applicability Source Text

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AD Number:
99-10-14
Document Type:
AD Final Rules
Docket Number:
98-NM-232-AD
Subject Heading:
Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes
Subject:
Instrument Landing System
Status:
Current
Citation:
(Federal Register: May 14, 1999 (Volume 64, Number 92))
Citation Publish Date:
05/14/1999
Effective Date:
06/17/1999
Make:
The Boeing Company
Model:
747-400 Series | 747-400D Series | 747-400F Series | 757-200 Series | 757-200CB Series | 757-200PF S...Show more
Product Type:
Aircraft
Product Subtype:
Large Airplane
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39 (64 FR 25804 NO. 92 05/14/99)
Comments:
AIRWORTHINESS DIRECTIVES FINAL RULES: 99-10-14
CITATION:   [Federal Register: May 14, 1999 (Volume 64, Number 92)]

PAGE NUMBER:   [Page 25804]

DOCKET NUMBER:   98-NM-232-AD

AMENDMENT:   39-11167

AD NUMBER:   99-10-14

SUBJECT HEADING:   Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes

ACTION:   Final rule

SUMMARY:  

DATES:   Effective June 17, 1999.

ADDRESSES:  
The service information referenced in this AD may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:  
Jay Yi, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Transport Airplane Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-1013; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION:  
A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 98-14-10, amendment 39-10643 (63 FR 36549, July 7, 1998), which is applicable to certain Boeing Model 747-400, 757, 767, and 777 series airplanes, was published in the Federal Register on October 26, 1998 (63 FR 57078). The action proposed to require a revision to the Airplane Flight Manual (AFM) to prohibit certain types of approaches, and repetitive inspections to detect certain faults of all RIA-35B ILS receivers. The action also proposed to require replacement of discrepant ILS receivers with new, serviceable, or modified units; or, alternatively, an additional revision to the AFM and installation of a placard to prohibit certain operations. In addition, the action proposed to require accomplishment of the previously optional terminating action.

Comments

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

One commenter supports the proposed rule. Two commenters indicate that they are not affected by the proposed rule. Another commenter states that it has already accomplished the proposed terminating action.

Conclusion

After careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

Cost Impact

There are approximately 74 airplanes of the affected design in the worldwide fleet. The FAA estimates that 74 airplanes of U.S. registry will be affected by this AD.

The AFM revision to prohibit certain types of approaches that currently is required by AD 98-14-10, and retained in this AD, takes approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the currently required AFM revision on U.S. operators is estimated to be $4,440, or $60 per airplane.

In lieu of the AFM revision and placard installation to prohibit certain types of operations, the visual inspection that currently is provided in AD 98-14-10 takes approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the inspection on U.S. operators is estimated to be $4,440, or $60 per airplane, per inspection cycle.

In lieu of the visual inspection, the AFM revision and placard installation that currently is provided in AD 98-14-10 takes approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the AFM revision and placard installation on U.S. operators is estimated to be $4,440, or $60 per airplane.

The new replacement that is required in this AD action will take approximately 3 work hours per airplane (1 work hour per receiver, 3 receivers per airplane) to accomplish, at an average labor rate of $60 per work hour. Required parts will cost approximately $235 per airplane ($78.33 per receiver). Based on these figures, the cost impact of the replacement required by this AD on U.S. operators is estimated to be $30,710, or $415 per airplane.

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact

The regulations adopted herein will not have substantial direct effects 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, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

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, Incorporation by reference, Safety.

Adoption of the Amendment
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 removing amendment 39-10643 (63 FR 36549, July 7, 1998), and by adding a new airworthiness directive (AD), amendment 39-11167, to read as follows:

REGULATORY TEXT:  
99-10-14 BOEING: Amendment 39-11167. Docket 98-NM-232-AD. Supersedes AD 98-14-10, Amendment 39-10643.

Applicability: Model 747-400, 757, 767, and 777 series airplanes; equipped with AlliedSignal RIA-35B Instrument Landing System (ILS) receivers, part number (P/N) 066-50006-0101, certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (e) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To prevent erroneous localizer deviation provided by faulty ILS receivers, which could result in a landing outside the lateral boundary of the runway, accomplish the following:

Restatement of the Requirements of AD 98-14-10

(a) Within 10 days after July 22, 1998 (the effective date of AD 98-14-10, amendment 39-10643), revise the Limitations Section of the FAA-approved Airplane Flight Manual (AFM) to include the following statement. This may be accomplished by inserting a copy of this AD into the AFM.

"Any Instrument Landing System (ILS) or Localizer approach with only one operative AlliedSignal LS receiver, P/N 066-50006-0101, installed is prohibited."

NOTE 2: On Model 747-400 and 777 series airplanes, the existence of only one operative ILS receiver is indicated by the Engine Indication and Crew Alerting System advisory message, "SNGL SOURCE ILS." On Model 757 and 767 series airplanes, failure of an ILS receiver is indicated by an ILS flag on the display of the Electronic Flight Instrument System when approach mode is selected.

(b) Within 30 days after July 22, 1998, accomplish the requirements of either paragraph (b)(1) or (b)(2) of this AD.

(1) Perform a visual inspection of the 64 flight legs of the internal fault memory of all AlliedSignal RIA-35B ILS receivers, P/N 066-50006-0101, for fault codes "Nl" (glide slope antialias fault) or "Nm" (localizer antialias fault). Repeat the inspection thereafter at intervals not to exceed 64 flight cycles. If any fault code "Nl" or "Nm" is found, prior to further flight, replace the existing ILS receiver with a new or serviceable ILS receiver having the same P/N; or with an ILS receiver that has been modified to P/N 066-50006-1101 in accordance with AlliedSignal Electronic and Avionics Systems Service Bulletin M-4426 (RIA-35B-34-6), Revision 3, dated May 1998. Installation of an ILS receiver that has been modified (and the P/N converted) in accordance with the service bulletin constitutes terminating action for the inspection requirement of paragraph (b)(1) of this AD for that part.

(2) Accomplish the actions required by paragraphs (b)(2)(i) and (b)(2)(ii) of this AD.

(i) Revise the Limitations Section of the FAA-approved AFM to include the following statement. This may be accomplished by inserting a copy of this AD into the AFM.

"Category II and III operations are prohibited with AlliedSignal ILS receiver P/N 066-50006-0101 installed."

(ii) Install a placard on the forward instrument panel of the cockpit in clear view of the pilots, which states:

"Category II and III operations are prohibited."

(c) As of July 22, 1998, no person shall install on any airplane an RIA-35B ILS receiver, P/N 066-50006-0101, that has been found to be discrepant (that is, on which fault codes "Nl" or "Nm" were found during an inspection of the internal fault memory) unless the discrepancy has been corrected by modifying the ILS receiver in accordance with AlliedSignal Electronic and Avionics Systems Service Bulletin M-4426 (RIA-35B-34-6), Revision 3, dated May 1998.

New Requirements of This AD

(d) Within 6 months after the effective date of this AD, replace all existing RIA-35B ILS receivers, P/N 066-50006-0101, with RIA-35B ILS receivers that have been modified in accordance with AlliedSignal Electronic and Avionics Systems Service Bulletin M-4426 (RIA-35B-34-6), Revision 3, dated May 1998; and that have had their P/N's converted to 066-50006-1101. Such replacement constitutes terminating action for the requirements of this AD. After the replacement has been accomplished, the AFM limitations required by paragraphs (a) and (b)(2)(i) of this AD may be removed from the AFM, and the placard required by (b)(2)(ii) may be removed from the cockpit.

NOTE 3: Modification of all AlliedSignal RIA-35B ILS receivers, P/N 066-50006-0101, prior to July 22, 1998, in accordance with AlliedSignal Electronic and Avionics Systems Service Bulletin M-4426 (RIA-35B-34-6), dated December 1997; Revision 1, dated January 1998; or Revision 2, dated April 1998; is considered acceptable for compliance with the applicable action specified in this amendment.

Alternative Methods of Compliance

(e) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO.

NOTE 4: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.

Special Flight Permits

(f) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

Incorporation by Reference

(g) The modification shall be done in accordance with AlliedSignal Electronic and Avionics Systems Service Bulletin M-4426 (RIA-35B-34-6), Revision 3, dated May 1998. The incorporation by reference of this document was approved previously by the Director of the Federal Register as of July 22, 1998 (63 FR 36549, July 7, 1998). Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
(h) This amendment becomes effective on June 17, 1999.

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Document Text

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AD Final Rules - DRS_99-10-14.html
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Document Versions
 Feedback
Details
AD Number:
99-10-14
Document Type:
AD Final Rules
Docket Number:
98-NM-232-AD
Subject Heading:
Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes
Subject:
Instrument Landing System
Status:
Current
Citation:
(Federal Register: May 14, 1999 (Volume 64, Number 92))
Citation Publish Date:
05/14/1999
Effective Date:
06/17/1999
Make:
The Boeing Company
Model:
747-400 Series | 747-400D Series | 747-400F Series | 757-200 Series | 757-200CB Series | 757-200PF S...Show more
Product Type:
Aircraft
Product Subtype:
Large Airplane
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39 (64 FR 25804 NO. 92 05/14/99)
Comments:
AIRWORTHINESS DIRECTIVES FINAL RULES: 99-10-14
CITATION:   [Federal Register: May 14, 1999 (Volume 64, Number 92)]

PAGE NUMBER:   [Page 25804]

DOCKET NUMBER:   98-NM-232-AD

AMENDMENT:   39-11167

AD NUMBER:   99-10-14

SUBJECT HEADING:   Airworthiness Directives; Boeing Model 747-400, 757, 767, and 777 Series Airplanes

ACTION:   Final rule

SUMMARY:  

DATES:   Effective June 17, 1999.

ADDRESSES:  
The service information referenced in this AD may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:  
Jay Yi, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Transport Airplane Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-1013; fax (425) 227-1181.

SUPPLEMENTARY INFORMATION:  
A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 98-14-10, amendment 39-10643 (63 FR 36549, July 7, 1998), which is applicable to certain Boeing Model 747-400, 757, 767, and 777 series airplanes, was published in the Federal Register on October 26, 1998 (63 FR 57078). The action proposed to require a revision to the Airplane Flight Manual (AFM) to prohibit certain types of approaches, and repetitive inspections to detect certain faults of all RIA-35B ILS receivers. The action also proposed to require replacement of discrepant ILS receivers with new, serviceable, or modified units; or, alternatively, an additional revision to the AFM and installation of a placard to prohibit certain operations. In addition, the action proposed to require accomplishment of the previously optional terminating action.

Comments

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

One commenter supports the proposed rule. Two commenters indicate that they are not affected by the proposed rule. Another commenter states that it has already accomplished the proposed terminating action.

Conclusion

After careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

Cost Impact

There are approximately 74 airplanes of the affected design in the worldwide fleet. The FAA estimates that 74 airplanes of U.S. registry will be affected by this AD.

The AFM revision to prohibit certain types of approaches that currently is required by AD 98-14-10, and retained in this AD, takes approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the currently required AFM revision on U.S. operators is estimated to be $4,440, or $60 per airplane.

In lieu of the AFM revision and placard installation to prohibit certain types of operations, the visual inspection that currently is provided in AD 98-14-10 takes approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the inspection on U.S. operators is estimated to be $4,440, or $60 per airplane, per inspection cycle.

In lieu of the visual inspection, the AFM revision and placard installation that currently is provided in AD 98-14-10 takes approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the AFM revision and placard installation on U.S. operators is estimated to be $4,440, or $60 per airplane.

The new replacement that is required in this AD action will take approximately 3 work hours per airplane (1 work hour per receiver, 3 receivers per airplane) to accomplish, at an average labor rate of $60 per work hour. Required parts will cost approximately $235 per airplane ($78.33 per receiver). Based on these figures, the cost impact of the replacement required by this AD on U.S. operators is estimated to be $30,710, or $415 per airplane.

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact

The regulations adopted herein will not have substantial direct effects 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, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

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, Incorporation by reference, Safety.

Adoption of the Amendment
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 removing amendment 39-10643 (63 FR 36549, July 7, 1998), and by adding a new airworthiness directive (AD), amendment 39-11167, to read as follows:

REGULATORY TEXT:  
99-10-14 BOEING: Amendment 39-11167. Docket 98-NM-232-AD. Supersedes AD 98-14-10, Amendment 39-10643.

Applicability: Model 747-400, 757, 767, and 777 series airplanes; equipped with AlliedSignal RIA-35B Instrument Landing System (ILS) receivers, part number (P/N) 066-50006-0101, certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (e) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To prevent erroneous localizer deviation provided by faulty ILS receivers, which could result in a landing outside the lateral boundary of the runway, accomplish the following:

Restatement of the Requirements of AD 98-14-10

(a) Within 10 days after July 22, 1998 (the effective date of AD 98-14-10, amendment 39-10643), revise the Limitations Section of the FAA-approved Airplane Flight Manual (AFM) to include the following statement. This may be accomplished by inserting a copy of this AD into the AFM.

"Any Instrument Landing System (ILS) or Localizer approach with only one operative AlliedSignal LS receiver, P/N 066-50006-0101, installed is prohibited."

NOTE 2: On Model 747-400 and 777 series airplanes, the existence of only one operative ILS receiver is indicated by the Engine Indication and Crew Alerting System advisory message, "SNGL SOURCE ILS." On Model 757 and 767 series airplanes, failure of an ILS receiver is indicated by an ILS flag on the display of the Electronic Flight Instrument System when approach mode is selected.

(b) Within 30 days after July 22, 1998, accomplish the requirements of either paragraph (b)(1) or (b)(2) of this AD.

(1) Perform a visual inspection of the 64 flight legs of the internal fault memory of all AlliedSignal RIA-35B ILS receivers, P/N 066-50006-0101, for fault codes "Nl" (glide slope antialias fault) or "Nm" (localizer antialias fault). Repeat the inspection thereafter at intervals not to exceed 64 flight cycles. If any fault code "Nl" or "Nm" is found, prior to further flight, replace the existing ILS receiver with a new or serviceable ILS receiver having the same P/N; or with an ILS receiver that has been modified to P/N 066-50006-1101 in accordance with AlliedSignal Electronic and Avionics Systems Service Bulletin M-4426 (RIA-35B-34-6), Revision 3, dated May 1998. Installation of an ILS receiver that has been modified (and the P/N converted) in accordance with the service bulletin constitutes terminating action for the inspection requirement of paragraph (b)(1) of this AD for that part.

(2) Accomplish the actions required by paragraphs (b)(2)(i) and (b)(2)(ii) of this AD.

(i) Revise the Limitations Section of the FAA-approved AFM to include the following statement. This may be accomplished by inserting a copy of this AD into the AFM.

"Category II and III operations are prohibited with AlliedSignal ILS receiver P/N 066-50006-0101 installed."

(ii) Install a placard on the forward instrument panel of the cockpit in clear view of the pilots, which states:

"Category II and III operations are prohibited."

(c) As of July 22, 1998, no person shall install on any airplane an RIA-35B ILS receiver, P/N 066-50006-0101, that has been found to be discrepant (that is, on which fault codes "Nl" or "Nm" were found during an inspection of the internal fault memory) unless the discrepancy has been corrected by modifying the ILS receiver in accordance with AlliedSignal Electronic and Avionics Systems Service Bulletin M-4426 (RIA-35B-34-6), Revision 3, dated May 1998.

New Requirements of This AD

(d) Within 6 months after the effective date of this AD, replace all existing RIA-35B ILS receivers, P/N 066-50006-0101, with RIA-35B ILS receivers that have been modified in accordance with AlliedSignal Electronic and Avionics Systems Service Bulletin M-4426 (RIA-35B-34-6), Revision 3, dated May 1998; and that have had their P/N's converted to 066-50006-1101. Such replacement constitutes terminating action for the requirements of this AD. After the replacement has been accomplished, the AFM limitations required by paragraphs (a) and (b)(2)(i) of this AD may be removed from the AFM, and the placard required by (b)(2)(ii) may be removed from the cockpit.

NOTE 3: Modification of all AlliedSignal RIA-35B ILS receivers, P/N 066-50006-0101, prior to July 22, 1998, in accordance with AlliedSignal Electronic and Avionics Systems Service Bulletin M-4426 (RIA-35B-34-6), dated December 1997; Revision 1, dated January 1998; or Revision 2, dated April 1998; is considered acceptable for compliance with the applicable action specified in this amendment.

Alternative Methods of Compliance

(e) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO.

NOTE 4: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.

Special Flight Permits

(f) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

Incorporation by Reference

(g) The modification shall be done in accordance with AlliedSignal Electronic and Avionics Systems Service Bulletin M-4426 (RIA-35B-34-6), Revision 3, dated May 1998. The incorporation by reference of this document was approved previously by the Director of the Federal Register as of July 22, 1998 (63 FR 36549, July 7, 1998). Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
(h) This amendment becomes effective on June 17, 1999.

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