AD 75-24-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 707-100 Long Body | BOEING Model 707 and 720 Series Airplanes |
| aircraft | The Boeing Company | 707-100B Long Body | BOEING Model 707 and 720 Series Airplanes |
| aircraft | The Boeing Company | 707-100B Short Body | BOEING Model 707 and 720 Series Airplanes |
| aircraft | The Boeing Company | 707-200 | BOEING Model 707 and 720 Series Airplanes |
| aircraft | The Boeing Company | 707-300 Series | BOEING Model 707 and 720 Series Airplanes |
| aircraft | The Boeing Company | 707-300B Series | BOEING Model 707 and 720 Series Airplanes |
| aircraft | The Boeing Company | 707-300C Series | BOEING Model 707 and 720 Series Airplanes |
| aircraft | The Boeing Company | 707-400 Series | BOEING Model 707 and 720 Series Airplanes |
| aircraft | The Boeing Company | 720 Series | BOEING Model 707 and 720 Series Airplanes |
| aircraft | The Boeing Company | 720B Series | BOEING Model 707 and 720 Series Airplanes |
Unsafe Condition
Cracks in the outer surface of the horizontal stabilizer center section rear spar upper chord assembly terminal lugs, initiating in the bushed holes at the terminal fittings.
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Required Actions
Visually inspect the horizontal stabilizer center section upper rear spar for cracks in the terminal lugs every 225 hours time in service, with an initial inspection due within 100 hours after the effective date if not done within the last 125 hours. If cracks are found, replace the assembly or repair by installing a strap per Boeing Drawing No. 65C15785 (replaceable after 3,000 hours) or modify per Boeing Service Bulletin No. 3243.
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Compliance Time
Within 100 hours time in service after the effective date, unless inspected within the last 125 hours time in service, and every 225 hours thereafter.
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Affected Aircraft
Boeing Model 707 and 720 series airplanes delivered after January 28, 1966 (including Serial Numbers 18955 and 18979), modified by Boeing Service Bulletin No. 2243 (Revisions 1-7), or had bushings removed for lug bore inspection/corrosion removal, with specified time-in-service thresholds.
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Federal Register Abstract
Horizontal Stabilizer Center Section Rear Spar Upper Chord Assembly
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_75-24-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-24-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Model 707 and 720 Series Airplanes Subject: Horizontal Stabilizer Center Section Rear Spar Upper Chord Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/24/1975 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: 75-24-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2425 AD NUMBER: 75-24-04 SUBJECT HEADING: BOEING Model 707 and 720 Series Airplanes ACTION: SUMMARY: DATES: Effective November 24, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-24-04 BOEING: Amendment 39-2425. Applies to all 707 and 720 series airplanes certificated in all categories which (1) were delivered after January 28, 1966, including Serial Numbers 18955 and 18979, with more than 12,000 hours time in service on the horizontal stabilizer center section rear spar upper chord assembly or (2) were modified by Boeing Service Bulletin No. 2243, Revisions 1 through 7, with more than 12,000 hours time in service since modified or (3) had the bushings removed for lug bore inspection and corrosion removal, with 12,000 hours or more time in service since the last flanged bushings were installed. Compliance required as indicated. A. Within 100 hours time in service after the effective date of this AD, unless inspected within the last 125 hours time in service, and every 225 hours thereafter, visually inspect the horizontal stabilizer center section upper rear spar for cracks in the outer surface of the right and left hand terminal lugs. The cracks initiate in the bushed holes at the terminal fittings. If cracks are found, replace the horizontal stabilizer center section rear spar upper chord assembly or repair prior to further flight in accordance with B or C below. B. Install a strap in accordance with Boeing Drawing No. 65C15785. This strap must be replaced in accordance with Boeing Drawing No. 65C15785 after 3,000 hours time in service. C. Modify in accordance with Boeing Service Bulletin No. 3243 or in a manner approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region. Such modification constitutes terminating action for this airworthiness directive. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive, who have not already received these documents from the manufacturer, may obtain copies upon request to Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124. The documents may also be examined at FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington. This amendment becomes effective November 24, 1975. FOOTER:
Document Text
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AD Final Rules - DRS_75-24-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-24-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Model 707 and 720 Series Airplanes Subject: Horizontal Stabilizer Center Section Rear Spar Upper Chord Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/24/1975 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: 75-24-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2425 AD NUMBER: 75-24-04 SUBJECT HEADING: BOEING Model 707 and 720 Series Airplanes ACTION: SUMMARY: DATES: Effective November 24, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-24-04 BOEING: Amendment 39-2425. Applies to all 707 and 720 series airplanes certificated in all categories which (1) were delivered after January 28, 1966, including Serial Numbers 18955 and 18979, with more than 12,000 hours time in service on the horizontal stabilizer center section rear spar upper chord assembly or (2) were modified by Boeing Service Bulletin No. 2243, Revisions 1 through 7, with more than 12,000 hours time in service since modified or (3) had the bushings removed for lug bore inspection and corrosion removal, with 12,000 hours or more time in service since the last flanged bushings were installed. Compliance required as indicated. A. Within 100 hours time in service after the effective date of this AD, unless inspected within the last 125 hours time in service, and every 225 hours thereafter, visually inspect the horizontal stabilizer center section upper rear spar for cracks in the outer surface of the right and left hand terminal lugs. The cracks initiate in the bushed holes at the terminal fittings. If cracks are found, replace the horizontal stabilizer center section rear spar upper chord assembly or repair prior to further flight in accordance with B or C below. B. Install a strap in accordance with Boeing Drawing No. 65C15785. This strap must be replaced in accordance with Boeing Drawing No. 65C15785 after 3,000 hours time in service. C. Modify in accordance with Boeing Service Bulletin No. 3243 or in a manner approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region. Such modification constitutes terminating action for this airworthiness directive. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive, who have not already received these documents from the manufacturer, may obtain copies upon request to Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124. The documents may also be examined at FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington. This amendment becomes effective November 24, 1975. FOOTER:
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