AD 64-25-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 707-100 Long Body | BOEING Models 707 and 720 Series Aircraft |
| aircraft | The Boeing Company | 707-100B Long Body | BOEING Models 707 and 720 Series Aircraft |
| aircraft | The Boeing Company | 707-100B Short Body | BOEING Models 707 and 720 Series Aircraft |
| aircraft | The Boeing Company | 707-200 | BOEING Models 707 and 720 Series Aircraft |
| aircraft | The Boeing Company | 707-300 Series | BOEING Models 707 and 720 Series Aircraft |
| aircraft | The Boeing Company | 707-300B Series | BOEING Models 707 and 720 Series Aircraft |
| aircraft | The Boeing Company | 707-300C Series | BOEING Models 707 and 720 Series Aircraft |
| aircraft | The Boeing Company | 707-400 Series | BOEING Models 707 and 720 Series Aircraft |
| aircraft | The Boeing Company | 720 Series | BOEING Models 707 and 720 Series Aircraft |
| aircraft | The Boeing Company | 720B Series | BOEING Models 707 and 720 Series Aircraft |
Unsafe Condition
Engine fires due to fuel accumulation in the aft thrust reverser sleeve and side cowl panel from false starts.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Drill or cut specified drain holes in the aft thrust reverser sleeve and left-hand side cowl panel as per Boeing Service Bulletin No. 1908 or an approved equivalent. Compliance must be completed within 3,100 hours' time in service after the AD's effective date.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 3,100 hours' time in service 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 Models 707 and 720 Series Aircraft equipped with Pratt & Whitney JT3D engines.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Cowl Panel and Aft Thrust Reverser Sleeve
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_64-25-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 64-25-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Models 707 and 720 Series Aircraft Subject: Cowl Panel and Aft Thrust Reverser Sleeve Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/07/1964 Make: The Boeing Company Model: 707-100 Long Body | 707-100B Long Body | 707-100B Short Body | 707-200 | 707-300 Series | 707-300B 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 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 64-25-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1 AD NUMBER: 64-25-01 SUBJECT HEADING: BOEING Models 707 and 720 Series Aircraft ACTION: SUMMARY: DATES: Effective December 7, 1964. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 64-25-01 BOEING: Amdt. 39-1 Part 507 Federal Register November 6, 1964. Applies to Models 707 and 720 Series Aircraft Equipped With Pratt & Whitney JT3D Engines. Compliance required as indicated. There have been a number of engine fires in service due to fuel accumulation in the aft thrust reverser sleeve and the side cowl panel as a result of false starts. To correct this condition, unless already accomplished, provide additional fluid drainage in the left-hand side cowl panel and aft thrust reverser sleeve on each engine in accordance with either (a) or (b) or an equivalent approved by the Aircraft Engineering Division, FAA Western Region. (a) Within 3,100 hours' time in service after the effective date of this AD accomplish the following: (1) Drill or cut four 1/2 inch-diameter holes through lower skin of the aft thrust reverser sleeve at Station 222.30 as shown on page 5 of Boeing Service Bulletin No. 1908. (2) Drill or cut two 1/4 inch-diameter holes through lower skin of aft thrust reverser sleeve at Station 222.30, one hole outboard of each channel section E-E and F-F at the locations shown on page 6 of Boeing Service Bulletin No. 1908. (3) Drill or cut two 1/2-inch diameter holes through lower skin of the aft thrust reverser sleeve at Station 241.75 as shown on page 4 of Boeing Service Bulletin No. 1908. (4) Drill or cut two 1/4 inch-diameter holes, one hole outboard of each rib, through lower skin on the aft thrust reverser sleeve, 1.3 inches outboard and 0.1 inch forward of each hole drilled in accordance with (a)(3). (5) Drill or cut two 1/2 inch-diameter holes through lower skin on left-hand side cowl nacelle Station 197.51 and bend trailing edge of each hole as shown on page 8 of Boeing Service Bulletin No. 1908. (b) Within 3,100 hours' time in service after the effective date of this AD, drill or cut additional 1/2 inch-diameter drain holes in the aft thrust reverser sleeve and in the left side cowl panel in accordance with Boeing Service Bulletin No. 1908. NOTE. - American Airlines, Inc. Fleet Campaign Directive No. 810B is an equivalent which has been approved by the Aircraft Engineering Division, FAA Western Region. (Boeing Service Bulletin No. 1908 dated January 16, 1964, covers this same subject.) This directive effective December 7, 1964. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_64-25-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 64-25-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Models 707 and 720 Series Aircraft Subject: Cowl Panel and Aft Thrust Reverser Sleeve Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/07/1964 Make: The Boeing Company Model: 707-100 Long Body | 707-100B Long Body | 707-100B Short Body | 707-200 | 707-300 Series | 707-300B 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 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 64-25-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1 AD NUMBER: 64-25-01 SUBJECT HEADING: BOEING Models 707 and 720 Series Aircraft ACTION: SUMMARY: DATES: Effective December 7, 1964. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 64-25-01 BOEING: Amdt. 39-1 Part 507 Federal Register November 6, 1964. Applies to Models 707 and 720 Series Aircraft Equipped With Pratt & Whitney JT3D Engines. Compliance required as indicated. There have been a number of engine fires in service due to fuel accumulation in the aft thrust reverser sleeve and the side cowl panel as a result of false starts. To correct this condition, unless already accomplished, provide additional fluid drainage in the left-hand side cowl panel and aft thrust reverser sleeve on each engine in accordance with either (a) or (b) or an equivalent approved by the Aircraft Engineering Division, FAA Western Region. (a) Within 3,100 hours' time in service after the effective date of this AD accomplish the following: (1) Drill or cut four 1/2 inch-diameter holes through lower skin of the aft thrust reverser sleeve at Station 222.30 as shown on page 5 of Boeing Service Bulletin No. 1908. (2) Drill or cut two 1/4 inch-diameter holes through lower skin of aft thrust reverser sleeve at Station 222.30, one hole outboard of each channel section E-E and F-F at the locations shown on page 6 of Boeing Service Bulletin No. 1908. (3) Drill or cut two 1/2-inch diameter holes through lower skin of the aft thrust reverser sleeve at Station 241.75 as shown on page 4 of Boeing Service Bulletin No. 1908. (4) Drill or cut two 1/4 inch-diameter holes, one hole outboard of each rib, through lower skin on the aft thrust reverser sleeve, 1.3 inches outboard and 0.1 inch forward of each hole drilled in accordance with (a)(3). (5) Drill or cut two 1/2 inch-diameter holes through lower skin on left-hand side cowl nacelle Station 197.51 and bend trailing edge of each hole as shown on page 8 of Boeing Service Bulletin No. 1908. (b) Within 3,100 hours' time in service after the effective date of this AD, drill or cut additional 1/2 inch-diameter drain holes in the aft thrust reverser sleeve and in the left side cowl panel in accordance with Boeing Service Bulletin No. 1908. NOTE. - American Airlines, Inc. Fleet Campaign Directive No. 810B is an equivalent which has been approved by the Aircraft Engineering Division, FAA Western Region. (Boeing Service Bulletin No. 1908 dated January 16, 1964, covers this same subject.) This directive effective December 7, 1964. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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