AD 64-16-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 720 Series | BOEING Model 720 Series Aircraft |
| aircraft | The Boeing Company | 720B Series | BOEING Model 720 Series Aircraft |
Unsafe Condition
Failures of bolts attaching the main landing gear centering cylinder and snubber assembly to the inner cylinder assembly and to the truck assembly have occurred.
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Required Actions
Replace existing bolts with larger diameter bolts per Boeing Service Bulletin No. 1570/1570A within 500 hours' time in service. Alternatively, replace 9/16 inch-diameter bolts with specified Standard Press Steel parts. Later, rework lugs and reinstall using specific bolts within 3,000 hours' time in service, extendable to 6,000 hours or next main landing gear overhaul.
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Compliance Time
Within the next 500 hours' time in service after the effective date of this AD
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Affected Aircraft
Boeing Model 720 Series and 720B Series aircraft
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Federal Register Abstract
Bolts Attaching the Main Landing Gear
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_64-16-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 64-16-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Model 720 Series Aircraft Subject: Bolts Attaching the Main Landing Gear Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/07/1964 Make: The Boeing Company Model: 720 Series | 720B Series Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 64-16-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 64-16-01 SUBJECT HEADING: BOEING Model 720 Series Aircraft ACTION: SUMMARY: DATES: Effective August 7, 1964 ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 64-16-01 BOEING: Amdt. 760 Part 507 Federal Register July 8, 1964. Applies to Model 720 Series Aircraft. Compliance required as indicated. Several failures of bolts attaching the main landing gear centering cylinder and snubber assembly to the inner cylinder assembly and to the truck assembly have occurred. To preclude further failures, the following or an equivalent approved by the Chief, Aircraft Engineering Division, FAA Western Region, shall be accomplished: (a) Within the next 500 hours' time in service after the effective date of this AD, unless already accomplished: (1) Replace the existing bolts attaching the main landing gear centering cylinder and snubber assembly to the inner cylinder assembly and to the truck assembly with larger diameter bolts specified in step (e) and in accordance with the provisions of the note following step (e) of paragraph 3, Modification Data of Boeing Service Bulletin No. 1570. The provisions of Boeing Service Bulletin No. 1570A shall also be accomplished; or (2) As an alternative, remove the existing 9/16 inch-diameter bolts, P/N's 63-9663 and 66-26031, and replace with 9/16 inch-diameter Standard Press Steel (SPS), P/N's 63425-9-24 and 63425-9-28 (H.T. 220,000 p.s.i. MIN.) respectively. The new bolts are to be reworked in accordance with the instructions on Figure 1 of Boeing Service Bulletin No. 1570, or later approved revisions to Boeing Service Bulletin No. 1570. (b) Within the next 3,000 hours' time in service after the effective date of this AD, accomplish the following, unless already accomplished: (1) Remove existing bolts, P/N's 63-9663 and 66-26031, or P/N's 63425-9-24 and 63425-9-28. (2) Rework terminal and inner cylinder lug per Figures 3 and 5 and steps 3b and 3c of Boeing Service Bulletins Nos. 1570 and 1570A respectively. (3) Rework truck assembly lug per Figure 4 and step 3d of Boeing Service Bulletins Nos. 1570 and 1570A. (4) Reinstall centering cylinder and snubber assembly using bolts 66-15739-1 and 66-15739-2 as shown in Figure 2 of Boeing Service Bulletin No. 1570. (c) The modifications in (a)(1) or (a)(2) need not be accomplished if the provisions of (b) are accomplished prior to the next 500 hours' time in service following the effective date of this AD. (d) Compliance with paragraph (b) may be extended to the next main landing gear overhaul or to 6,000 hours' time in service after the effective date of this AD, whichever occurs first, if the following is accomplished: (1) Operators who have complied with (a)(1) shall replace the bushings prior to 3,000 hours' time in service after the bushing has been reworked. (2) Operators who have complied with (a)(2) shall replace the bolts at periods not to exceed 2,000 hours' time in service until (b) is accomplished. (Boeing Service Bulletins Nos. 1570 and 1570A cover this same subject.) This directive effective August 7, 1964. FOOTER:
Document Text
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AD Final Rules - DRS_64-16-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 64-16-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Model 720 Series Aircraft Subject: Bolts Attaching the Main Landing Gear Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/07/1964 Make: The Boeing Company Model: 720 Series | 720B 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 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 64-16-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 64-16-01 SUBJECT HEADING: BOEING Model 720 Series Aircraft ACTION: SUMMARY: DATES: Effective August 7, 1964 ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 64-16-01 BOEING: Amdt. 760 Part 507 Federal Register July 8, 1964. Applies to Model 720 Series Aircraft. Compliance required as indicated. Several failures of bolts attaching the main landing gear centering cylinder and snubber assembly to the inner cylinder assembly and to the truck assembly have occurred. To preclude further failures, the following or an equivalent approved by the Chief, Aircraft Engineering Division, FAA Western Region, shall be accomplished: (a) Within the next 500 hours' time in service after the effective date of this AD, unless already accomplished: (1) Replace the existing bolts attaching the main landing gear centering cylinder and snubber assembly to the inner cylinder assembly and to the truck assembly with larger diameter bolts specified in step (e) and in accordance with the provisions of the note following step (e) of paragraph 3, Modification Data of Boeing Service Bulletin No. 1570. The provisions of Boeing Service Bulletin No. 1570A shall also be accomplished; or (2) As an alternative, remove the existing 9/16 inch-diameter bolts, P/N's 63-9663 and 66-26031, and replace with 9/16 inch-diameter Standard Press Steel (SPS), P/N's 63425-9-24 and 63425-9-28 (H.T. 220,000 p.s.i. MIN.) respectively. The new bolts are to be reworked in accordance with the instructions on Figure 1 of Boeing Service Bulletin No. 1570, or later approved revisions to Boeing Service Bulletin No. 1570. (b) Within the next 3,000 hours' time in service after the effective date of this AD, accomplish the following, unless already accomplished: (1) Remove existing bolts, P/N's 63-9663 and 66-26031, or P/N's 63425-9-24 and 63425-9-28. (2) Rework terminal and inner cylinder lug per Figures 3 and 5 and steps 3b and 3c of Boeing Service Bulletins Nos. 1570 and 1570A respectively. (3) Rework truck assembly lug per Figure 4 and step 3d of Boeing Service Bulletins Nos. 1570 and 1570A. (4) Reinstall centering cylinder and snubber assembly using bolts 66-15739-1 and 66-15739-2 as shown in Figure 2 of Boeing Service Bulletin No. 1570. (c) The modifications in (a)(1) or (a)(2) need not be accomplished if the provisions of (b) are accomplished prior to the next 500 hours' time in service following the effective date of this AD. (d) Compliance with paragraph (b) may be extended to the next main landing gear overhaul or to 6,000 hours' time in service after the effective date of this AD, whichever occurs first, if the following is accomplished: (1) Operators who have complied with (a)(1) shall replace the bushings prior to 3,000 hours' time in service after the bushing has been reworked. (2) Operators who have complied with (a)(2) shall replace the bolts at periods not to exceed 2,000 hours' time in service until (b) is accomplished. (Boeing Service Bulletins Nos. 1570 and 1570A cover this same subject.) This directive effective August 7, 1964. FOOTER:
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