AD 94-21-05 R1
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 737-300 Series | Airworthiness Directives; Boeing Model 737-300, -400, and -500 Series Airplanes |
| aircraft | The Boeing Company | 737-400 Series | Airworthiness Directives; Boeing Model 737-300, -400, and -500 Series Airplanes |
| aircraft | The Boeing Company | 737-500 Series | Airworthiness Directives; Boeing Model 737-300, -400, and -500 Series Airplanes |
Unsafe Condition
Deployment of a thrust reverser in flight and subsequent reduced controllability of the airplane.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Accomplish the Thrust Reverser Sync-Lock Integrity Test at intervals not to exceed 4,000 hours time-in-service. If discrepancies are found, repair them per the Boeing 737 Maintenance Manual or deactivate the associated thrust reverser per MMEL limitations and verify the failed sync-lock is in the locked position.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 4,000 hours time-in-service after accomplishing the modification or after the effective date of this AD, whichever occurs later; and thereafter at intervals not to exceed 4,000 hours time-in-service.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Boeing Model 737-300, -400, and -500 series airplanes equipped with CFM International CFM56-3 series engines.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Thrust Reverser
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_94-21-05_R.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 94-21-05 R1 Document Type: AD Final Rules Docket Number: 93-NM-122-AD Subject Heading: Airworthiness Directives; Boeing Model 737-300, -400, and -500 Series Airplanes Subject: Thrust Reverser Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/25/1994 Make: The Boeing Company Model: 737-300 Series | 737-400 Series | 737-500 Series Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 (60 FR 36974 NO. 138 7/19/95) Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 94-21-05 R1 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 93-NM-122-AD AMENDMENT: 39-9314 AD NUMBER: 94-21-05 R1 SUBJECT HEADING: Airworthiness Directives; Boeing Model 737-300, -400, and -500 Series Airplanes ACTION: Final rule; correction SUMMARY: This amendment clarifies an existing airworthiness directive (AD), applicable to certain Boeing Model 737-300, -400, and -500 series airplanes, that currently requires modification, adjustments, and tests of the thrust reverser system; and repair, if necessary. This amendment clarifies a requirement specified in the AD concerning the performance of the operational test of the system. This amendment is prompted by an inquiry from an operator of the affected airplanes concerning that aspect of the existing AD. The incorporation by reference of certain publications listed in the regulations was approved by the Director of the Federal Register as of November 25, 1994 (59 FR 53573, October 25, 1994). DATES: Effective November 25, 1994. 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 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. FOR FURTHER INFORMATION CONTACT: Stephen Bray, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington; telephone (206) 227-2681; fax (206) 227-1181. SUPPLEMENTARY INFORMATION: On October 6, 1994, the FAA issued AD 94-21-05, amendment 39-9047 (59 FR 53573, October 25, 1994), applicable to certain Boeing Model 737-300, -400, and -500 series airplanes, to require modification, adjustments, and tests of the thrust reverser system; and repair, if necessary. The actions required by that AD are intended to prevent deployment of a thrust reverser in flight and subsequent reduced controllability of the airplane. Since the issuance of that AD, the FAA has received an inquiry from an operator of the affected airplanes concerning the requirement of paragraph (d)(2) of the AD. That paragraph requires deactivation of a thrust reverser if a discrepancy is found during accomplishment of the thrust reverser sync-lock integrity test. The last sentence of paragraph (d)(2) specifies that, following deactivation of the associated thrust reverser, "the sync-locks installed on the deactivated thrust reverser must remain operational." The operator questions how the sync-lock can remain "operational" when the thrust reverser has been deactivated for failing the required integrity test. The FAA finds that clarification of the term "operational" is necessary. The FAA's intent in specifying that the sync-lock remain operational was actually to require that it be verified to be in the locked position. In order to avoid unnecessary flight delays and cancellations, the FAA included the provision contained in paragraph (d)(2) of AD 94-21-05 to provide relief to allow dispatch of the airplane with deactivated sync-locks, in accordance with provisions and limitations contained in the Master Minimum Equipment List (MMEL). This relief involves locking out a thrust reverser and verifying that the failed sync-lock is deactivated and in the locked position. In light of this, action is taken herein to revise AD 94-21-05 to clarify paragraph (d)(2) of the AD accordingly. There are no other changes to the rule. The final rule is being reprinted in its entirety for the convenience of affected operators. The effective date remains November 25, 1994. Since this action only clarifies a requirement of a final rule, it has no adverse economic impact and imposes no additional burden on any person. Therefore, notice and public procedures hereon are unnecessary. 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. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89. § 39.13 - [Amended] 2. Section 39.13 is amended by removing amendment 39-9047 (59 FR 53573, October 25, 1994), and by adding a new airworthiness directive (AD), amendment 39-9314, to read as follows: REGULATORY TEXT: 94-21-05 R1 BOEING: Amendment 39-9314. Docket 93-NM-122-AD. Revises AD 94-21-05, Amendment 39-9047. Applicability: Model 737-300, -400, and -500 series airplanes equipped with CFM International CFM56-3 series engines, certificated in any category. Compliance: Required as indicated, unless accomplished previously. To prevent deployment of a thrust reverser in flight and subsequent reduced ontrollability of the airplane, accomplish the following: (a) For airplanes on which the sync-lock installation [specified in paragraph (b) of this AD], sync-lock wiring modification [specified in paragraph (c) of this AD], or Production Revision Record (PRR) 35105 has not been accomplished: Within 60 days after the effective date of this AD, and thereafter at intervals not to exceed 4,000 hours time-in-service, perform adjustments and tests of the thrust reverser system that are specified in Section 78-31-00 of the Boeing 737 Maintenance Manual to verify proper operation of the thrust reverser system, in accordance with that section of the maintenance manual. If any discrepancy is found, prior to further flight, accomplish either paragraph (a)(1) or (a)(2) of this AD. (1) Repair any discrepancy found, in accordance with procedures described in the Boeing 737 Maintenance Manual. Or (2) Deactivate the associated thrust reverser in accordance with the existing provisions and limitations specified in the Master Minimum Equipment List (MMEL). (b) For airplanes on which the sync-lock feature was not installed during production or as a modification in accordance with Boeing Service Bulletin 737-78-1053, dated December 17, 1992: Within 5 years after the effective date of this AD, install an additional thrust reverser system locking feature (sync-lock installation) in accordance with Boeing Service Bulletin 737-78- 1053, Revision 1, dated July 1, 1993; Revision 2, dated February 17, 1994; or Revision 3, dated June 30, 1994. Installation of the additional locking feature constitutes terminating action for the tests required by paragraph (a) of this AD. (c) For airplanes listed in Boeing Service Bulletin 737-78-1058, dated July 1, 1993: Within 5 years after the effective date of this AD, modify the sync-lock wiring in accordance with Boeing Service Bulletin 737-78-1058, dated July 1, 1993; Revision 1, dated February 17, 1994; or Revision 2, dated July 7, 1994. Modification of the sync-lock wiring constitutes terminating action for the tests required by paragraph (a) of this AD. (d) At the times specified in paragraph (e) of this AD, accomplish the "Thrust Reverser Sync-Lock Integrity Test" specified below to verify that the sync-locks are not failing in the unlocked state. If any discrepancy is found, prior to further flight, accomplish paragraph (d)(1) or (d)(2) of this AD. (1) Repair any discrepancy found, in accordance with procedures specified in the Boeing 737 Maintenance Manual. Or (2) Deactivate the associated thrust reverser in accordance with the existing provisions and limitations specified in the MMEL; and verify that the failed sync-lock is deactivated and in the locked position. "THRUST REVERSER SYNC-LOCK INTEGRITY TEST 1. General A. Use this procedure to test the integrity of the thrust reverser sync-locks. The procedure must be performed on each engine. 2. Thrust Reverser Sync-Lock Test A. Prepare for the Thrust Reverser Sync-Lock test. (1) Do the steps that follow to supply power to the thrust reverser system: (a) Make sure the thrust levers are in the idle position. (b) Make sure the thrust reversers are retracted and locked. (c) Make sure these circuit breakers on the P6 circuit breaker panel are closed: 1) ENGINE 1 THRUST REVERSER CONT SYS 2) ENGINE 2 THRUST REVERSER CONT SYS 3) ENGINE 2 THRUST REVERSER CONT SYS-ALT 4) ENGINE 1 THRUST REVERSER IND SYS 5) ENGINE 2 THRUST REVERSER IND SYS 6) ENGINE 1 SYNC-LOCK 7) ENGINE 2 SYNC-LOCK 8) ENGINE 2 SYNC-LOCK-ALTN 9) LANDING GEAR AIR/GND RELAY AND LIGHTS 10) RADIO ALTM-2 (d) Make sure this circuit breaker on the P18 circuit breaker panel is closed: 1) RADIO ALTM-1 (e) Supply electrical power. (f) Remove pressure from the A (for the left engine) or B (for the right engine) hydraulic system. B. Do the thrust reverser sync-lock test. (1) Move and hold the manual unlock lever on the upper actuator on both thrust reverser sleeves to the unlock position. (2) Make sure the thrust reverser sleeves did not move aft. (3) Move the left (right) reverse thrust lever up and rearward to the reverse thrust position. (4) Make sure both thrust reverser sleeves move aft (approximately 0.15 to 0.25 inch). (5) Release the manual unlock lever on the upper actuators. WARNING: MAKE SURE ALL PERSONS AND EQUIPMENT ARE CLEAR OF THE AREA AROUND THE THRUST REVERSER. WHEN YOU APPLY HYDRAULIC PRESSURE, THE THRUST REVERSER WILL EXTEND AND CAN CAUSE INJURIES TO PERSONS OR DAMAGE TO EQUIPMENT. (6) Pressurize the A (B) hydraulic system. (7) Make sure the thrust reverser extends. (8) Move the left (right) reverse thrust lever to the forward and down position to retract the thrust reverser. C. Put the airplane back to its usual condition. (1) Remove hydraulic pressure. (2) Remove electrical power. D. Repeat the thrust reverser sync-lock test on the other engine." (e) Accomplish the test required by paragraph (d) of this AD at the times specified in paragraph (e)(1) or (e)(2) of this AD, as applicable. (1) For airplanes that are subject to the requirements of paragraphs (b) and (c) of this AD: Within 4,000 hours time-in-service after accomplishing the modification required by paragraph (b) or (c) of this AD, as applicable, or within 4,000 hours time-in-service after the effective date of this AD, whichever occurs later; and thereafter at intervals not to exceed 4,000 hours time-in-service. (2) For all other airplanes: Within 4,000 total hours time-in-service, or within 4,000 hours time-in-service after the effective date of this AD, whichever occurs later; and thereafter at intervals not to exceed 4,000 hours time-in-service. (f) 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: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. (g) 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. (h) The installation and wiring modification shall be done in accordance with Boeing Service Bulletin 737-78-1053, Revision 1, dated July 1, 1993; Boeing Service Bulletin 737-78- 1053, Revision 2, dated February 17, 1994; Boeing Service Bulletin 737-78-1053, Revision 3, dated June 30, 1994; Boeing Service Bulletin 737-78-1058, dated July 1, 1993; Boeing Service Bulletin 737-78-1058, Revision 1, dated February 17, 1994; or Boeing Service Bulletin 737-78- 1058, Revision 2, dated July 7, 1994. The incorporation by reference of this document was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51 as of November 25, 1994 (59 FR 53573, October 25, 1994). 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. (i) This amendment is effective on November 25, 1994. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_94-21-05_R.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 94-21-05 R1 Document Type: AD Final Rules Docket Number: 93-NM-122-AD Subject Heading: Airworthiness Directives; Boeing Model 737-300, -400, and -500 Series Airplanes Subject: Thrust Reverser Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/25/1994 Make: The Boeing Company Model: 737-300 Series | 737-400 Series | 737-500 Series 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 (60 FR 36974 NO. 138 7/19/95) Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 94-21-05 R1 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 93-NM-122-AD AMENDMENT: 39-9314 AD NUMBER: 94-21-05 R1 SUBJECT HEADING: Airworthiness Directives; Boeing Model 737-300, -400, and -500 Series Airplanes ACTION: Final rule; correction SUMMARY: This amendment clarifies an existing airworthiness directive (AD), applicable to certain Boeing Model 737-300, -400, and -500 series airplanes, that currently requires modification, adjustments, and tests of the thrust reverser system; and repair, if necessary. This amendment clarifies a requirement specified in the AD concerning the performance of the operational test of the system. This amendment is prompted by an inquiry from an operator of the affected airplanes concerning that aspect of the existing AD. The incorporation by reference of certain publications listed in the regulations was approved by the Director of the Federal Register as of November 25, 1994 (59 FR 53573, October 25, 1994). DATES: Effective November 25, 1994. 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 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. FOR FURTHER INFORMATION CONTACT: Stephen Bray, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington; telephone (206) 227-2681; fax (206) 227-1181. SUPPLEMENTARY INFORMATION: On October 6, 1994, the FAA issued AD 94-21-05, amendment 39-9047 (59 FR 53573, October 25, 1994), applicable to certain Boeing Model 737-300, -400, and -500 series airplanes, to require modification, adjustments, and tests of the thrust reverser system; and repair, if necessary. The actions required by that AD are intended to prevent deployment of a thrust reverser in flight and subsequent reduced controllability of the airplane. Since the issuance of that AD, the FAA has received an inquiry from an operator of the affected airplanes concerning the requirement of paragraph (d)(2) of the AD. That paragraph requires deactivation of a thrust reverser if a discrepancy is found during accomplishment of the thrust reverser sync-lock integrity test. The last sentence of paragraph (d)(2) specifies that, following deactivation of the associated thrust reverser, "the sync-locks installed on the deactivated thrust reverser must remain operational." The operator questions how the sync-lock can remain "operational" when the thrust reverser has been deactivated for failing the required integrity test. The FAA finds that clarification of the term "operational" is necessary. The FAA's intent in specifying that the sync-lock remain operational was actually to require that it be verified to be in the locked position. In order to avoid unnecessary flight delays and cancellations, the FAA included the provision contained in paragraph (d)(2) of AD 94-21-05 to provide relief to allow dispatch of the airplane with deactivated sync-locks, in accordance with provisions and limitations contained in the Master Minimum Equipment List (MMEL). This relief involves locking out a thrust reverser and verifying that the failed sync-lock is deactivated and in the locked position. In light of this, action is taken herein to revise AD 94-21-05 to clarify paragraph (d)(2) of the AD accordingly. There are no other changes to the rule. The final rule is being reprinted in its entirety for the convenience of affected operators. The effective date remains November 25, 1994. Since this action only clarifies a requirement of a final rule, it has no adverse economic impact and imposes no additional burden on any person. Therefore, notice and public procedures hereon are unnecessary. 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. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89. § 39.13 - [Amended] 2. Section 39.13 is amended by removing amendment 39-9047 (59 FR 53573, October 25, 1994), and by adding a new airworthiness directive (AD), amendment 39-9314, to read as follows: REGULATORY TEXT: 94-21-05 R1 BOEING: Amendment 39-9314. Docket 93-NM-122-AD. Revises AD 94-21-05, Amendment 39-9047. Applicability: Model 737-300, -400, and -500 series airplanes equipped with CFM International CFM56-3 series engines, certificated in any category. Compliance: Required as indicated, unless accomplished previously. To prevent deployment of a thrust reverser in flight and subsequent reduced ontrollability of the airplane, accomplish the following: (a) For airplanes on which the sync-lock installation [specified in paragraph (b) of this AD], sync-lock wiring modification [specified in paragraph (c) of this AD], or Production Revision Record (PRR) 35105 has not been accomplished: Within 60 days after the effective date of this AD, and thereafter at intervals not to exceed 4,000 hours time-in-service, perform adjustments and tests of the thrust reverser system that are specified in Section 78-31-00 of the Boeing 737 Maintenance Manual to verify proper operation of the thrust reverser system, in accordance with that section of the maintenance manual. If any discrepancy is found, prior to further flight, accomplish either paragraph (a)(1) or (a)(2) of this AD. (1) Repair any discrepancy found, in accordance with procedures described in the Boeing 737 Maintenance Manual. Or (2) Deactivate the associated thrust reverser in accordance with the existing provisions and limitations specified in the Master Minimum Equipment List (MMEL). (b) For airplanes on which the sync-lock feature was not installed during production or as a modification in accordance with Boeing Service Bulletin 737-78-1053, dated December 17, 1992: Within 5 years after the effective date of this AD, install an additional thrust reverser system locking feature (sync-lock installation) in accordance with Boeing Service Bulletin 737-78- 1053, Revision 1, dated July 1, 1993; Revision 2, dated February 17, 1994; or Revision 3, dated June 30, 1994. Installation of the additional locking feature constitutes terminating action for the tests required by paragraph (a) of this AD. (c) For airplanes listed in Boeing Service Bulletin 737-78-1058, dated July 1, 1993: Within 5 years after the effective date of this AD, modify the sync-lock wiring in accordance with Boeing Service Bulletin 737-78-1058, dated July 1, 1993; Revision 1, dated February 17, 1994; or Revision 2, dated July 7, 1994. Modification of the sync-lock wiring constitutes terminating action for the tests required by paragraph (a) of this AD. (d) At the times specified in paragraph (e) of this AD, accomplish the "Thrust Reverser Sync-Lock Integrity Test" specified below to verify that the sync-locks are not failing in the unlocked state. If any discrepancy is found, prior to further flight, accomplish paragraph (d)(1) or (d)(2) of this AD. (1) Repair any discrepancy found, in accordance with procedures specified in the Boeing 737 Maintenance Manual. Or (2) Deactivate the associated thrust reverser in accordance with the existing provisions and limitations specified in the MMEL; and verify that the failed sync-lock is deactivated and in the locked position. "THRUST REVERSER SYNC-LOCK INTEGRITY TEST 1. General A. Use this procedure to test the integrity of the thrust reverser sync-locks. The procedure must be performed on each engine. 2. Thrust Reverser Sync-Lock Test A. Prepare for the Thrust Reverser Sync-Lock test. (1) Do the steps that follow to supply power to the thrust reverser system: (a) Make sure the thrust levers are in the idle position. (b) Make sure the thrust reversers are retracted and locked. (c) Make sure these circuit breakers on the P6 circuit breaker panel are closed: 1) ENGINE 1 THRUST REVERSER CONT SYS 2) ENGINE 2 THRUST REVERSER CONT SYS 3) ENGINE 2 THRUST REVERSER CONT SYS-ALT 4) ENGINE 1 THRUST REVERSER IND SYS 5) ENGINE 2 THRUST REVERSER IND SYS 6) ENGINE 1 SYNC-LOCK 7) ENGINE 2 SYNC-LOCK 8) ENGINE 2 SYNC-LOCK-ALTN 9) LANDING GEAR AIR/GND RELAY AND LIGHTS 10) RADIO ALTM-2 (d) Make sure this circuit breaker on the P18 circuit breaker panel is closed: 1) RADIO ALTM-1 (e) Supply electrical power. (f) Remove pressure from the A (for the left engine) or B (for the right engine) hydraulic system. B. Do the thrust reverser sync-lock test. (1) Move and hold the manual unlock lever on the upper actuator on both thrust reverser sleeves to the unlock position. (2) Make sure the thrust reverser sleeves did not move aft. (3) Move the left (right) reverse thrust lever up and rearward to the reverse thrust position. (4) Make sure both thrust reverser sleeves move aft (approximately 0.15 to 0.25 inch). (5) Release the manual unlock lever on the upper actuators. WARNING: MAKE SURE ALL PERSONS AND EQUIPMENT ARE CLEAR OF THE AREA AROUND THE THRUST REVERSER. WHEN YOU APPLY HYDRAULIC PRESSURE, THE THRUST REVERSER WILL EXTEND AND CAN CAUSE INJURIES TO PERSONS OR DAMAGE TO EQUIPMENT. (6) Pressurize the A (B) hydraulic system. (7) Make sure the thrust reverser extends. (8) Move the left (right) reverse thrust lever to the forward and down position to retract the thrust reverser. C. Put the airplane back to its usual condition. (1) Remove hydraulic pressure. (2) Remove electrical power. D. Repeat the thrust reverser sync-lock test on the other engine." (e) Accomplish the test required by paragraph (d) of this AD at the times specified in paragraph (e)(1) or (e)(2) of this AD, as applicable. (1) For airplanes that are subject to the requirements of paragraphs (b) and (c) of this AD: Within 4,000 hours time-in-service after accomplishing the modification required by paragraph (b) or (c) of this AD, as applicable, or within 4,000 hours time-in-service after the effective date of this AD, whichever occurs later; and thereafter at intervals not to exceed 4,000 hours time-in-service. (2) For all other airplanes: Within 4,000 total hours time-in-service, or within 4,000 hours time-in-service after the effective date of this AD, whichever occurs later; and thereafter at intervals not to exceed 4,000 hours time-in-service. (f) 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: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. (g) 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. (h) The installation and wiring modification shall be done in accordance with Boeing Service Bulletin 737-78-1053, Revision 1, dated July 1, 1993; Boeing Service Bulletin 737-78- 1053, Revision 2, dated February 17, 1994; Boeing Service Bulletin 737-78-1053, Revision 3, dated June 30, 1994; Boeing Service Bulletin 737-78-1058, dated July 1, 1993; Boeing Service Bulletin 737-78-1058, Revision 1, dated February 17, 1994; or Boeing Service Bulletin 737-78- 1058, Revision 2, dated July 7, 1994. The incorporation by reference of this document was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51 as of November 25, 1994 (59 FR 53573, October 25, 1994). 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. (i) This amendment is effective on November 25, 1994. FOOTER:
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