AD 74-10-13
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 707-100 Long Body | BOEING Model 707 and 720 Airplanes |
| aircraft | The Boeing Company | 707-100B Long Body | BOEING Model 707 and 720 Airplanes |
| aircraft | The Boeing Company | 707-100B Short Body | BOEING Model 707 and 720 Airplanes |
| aircraft | The Boeing Company | 707-200 | BOEING Model 707 and 720 Airplanes |
| aircraft | The Boeing Company | 707-300 Series | BOEING Model 707 and 720 Airplanes |
| aircraft | The Boeing Company | 707-300B Series | BOEING Model 707 and 720 Airplanes |
| aircraft | The Boeing Company | 707-300C Series | BOEING Model 707 and 720 Airplanes |
| aircraft | The Boeing Company | 707-400 Series | BOEING Model 707 and 720 Airplanes |
| aircraft | The Boeing Company | 720 Series | BOEING Model 707 and 720 Airplanes |
| aircraft | The Boeing Company | 720B Series | BOEING Model 707 and 720 Airplanes |
Unsafe Condition
Excessive non-recoverable internal hydraulic leakage in the auxiliary hydraulic system and possible loss of aircraft direction control at critical air speeds.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect auxiliary hydraulic system for internal leakage per Boeing Alert Service Bulletin 3154 or equivalent method. Replace or rework components if leakage is 1.0 GPM or greater. For leakage ≥3.0 GPM, replace or overhaul components before further flight. Adjust inspection intervals with FAA approval.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within specified intervals (300 or 600 hours time in service after effective date, then every 2,000 hours time in service).
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Boeing Model 707 and 720 airplanes with 6,000 hours or more time in service.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Auxiliary Hydraulic System
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_74-10-13.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-10-13 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Model 707 and 720 Airplanes Subject: Auxiliary Hydraulic System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/14/1974 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: 74-10-13 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1845 AD NUMBER: 74-10-13 SUBJECT HEADING: BOEING Model 707 and 720 Airplanes ACTION: SUMMARY: DATES: Effective May 14, 1974. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-10-13 BOEING: Amendment 39-1845. Applies to all Model 707 and 720 airplanes having 6,000 hrs., or more, time in service, certificated in all categories. Compliance is required as indicated, unless already accomplished. To prevent excessive non-recoverable internal hydraulic leakage in the auxiliary hydraulic system and the possible loss of aircraft direction control at critical air speeds, accomplish the following: PART I (a) PART I of this AD applies to airplanes which will be used for flight crew training. (b) Prior to further flight for crew training, and thereafter at intervals not to exceed 2,000 hours time in service from the last inspection, the airplane auxiliary hydraulic system must be inspected and replaced or reworked, as necessary, in accordance with the following: (1) Inspect for evidence of internal leakage per the information contained in Boeing Alert Service Bulletin 3154 dated April 12, 1974, or later FAA approved revisions of Boeing Alert Service Bulletin 3154 or by an equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region. (2) Airplanes with an auxiliary hydraulic system having internal leakage equal to or greater than 1.0 GPM but less than 3.0 GPM may not be used in training or revenue service but may only be flown in accordance with FAR 21.197 to a maintenance base for replacement or rework, as necessary, of the defective auxiliary hydraulic system components. (3) Airplanes with an auxiliary hydraulic system having 3.0 GPM, or more, internal leakage must have the defective auxiliary hydraulic system components replaced or overhauled, as necessary, prior to further flight. PART II (a) PART II of this AD applies to airplanes which have not been inspected and reworked, as necessary, in accordance with Amendment 39-1753 (F. R. Doc. 73-25927), AD-73-25-2. (b) Within 300 hours time in service after the effective date of this AD, and thereafter at intervals not to exceed 2,000 hours time in service from the last inspection, accomplish the following: (1) Inspect for evidence of internal leakage and replace or rework, as necessary, per the information contained in Boeing Alert Service Bulletin 3154 dated April 12, 1974, or later FAA approved revisions of Boeing Alert Service Bulletin 3154 or by an equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region. (2) Airplanes with an auxiliary hydraulic system having internal leakage equal to or greater than 1.0 GPM but less than 3.0 GPM may not be used in revenue service but may only be flown in accordance with FAR 21.197 to a maintenance base for replacement or rework, as necessary, of the defective auxiliary hydraulic components. (3) Airplanes with an auxiliary hydraulic system having 3.0 GPM, or more, internal leakage must have the defective auxiliary hydraulic system components replaced or overhauled, as necessary, prior to further flight. PART III (a) PART III of this AD applies to airplanes which have been inspected and reworked, as necessary, in accordance with Amendment 39-1753 (F. R. Doc. 73-25927), AD-73-25-2. (b) Within 600 hours time in service after the effective date of this AD and thereafter at intervals not to exceed 2,000 hours time in service from the last inspection, accomplish the following: (1) Inspect for evidence of internal leakage and replace or rework, as necessary, per the information contained in Boeing Alert Service Bulletin 3154 dated April 12, 1974, or later FAA approved revisions of Boeing Alert Service Bulletin 3154, or by an equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region. (2) Airplanes with an auxiliary hydraulic system having internal leakage equal to or greater than 1.0 GPM but less than 3.0 GPM, may not be used in revenue service but may only be flown in accordance with FAR 21.197 to a maintenance base for replacement or rework, as necessary, of the defective auxiliary hydraulic system components. (3) Airplanes with an auxiliary hydraulic system having 3.0 GPM, or more, internal leakage must have the defective auxiliary hydraulic system components replaced or overhauled, as necessary, prior to further flight. For the purpose of complying with the repetitive periodic inspection requirement of this AD, the 2,000 hours time in service may be adjusted by submitting substantiating technical data through the FAA assigned maintenance inspector for the approval of the Chief, Engineering and Manufacturing Branch, Flight Standards Division, FAA, Northwest Region. This AD Amendment 39-1845 supersedes AD 73-25-2. This Amendment becomes effective May 14, 1974. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_74-10-13.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-10-13 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Model 707 and 720 Airplanes Subject: Auxiliary Hydraulic System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/14/1974 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: 74-10-13 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1845 AD NUMBER: 74-10-13 SUBJECT HEADING: BOEING Model 707 and 720 Airplanes ACTION: SUMMARY: DATES: Effective May 14, 1974. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-10-13 BOEING: Amendment 39-1845. Applies to all Model 707 and 720 airplanes having 6,000 hrs., or more, time in service, certificated in all categories. Compliance is required as indicated, unless already accomplished. To prevent excessive non-recoverable internal hydraulic leakage in the auxiliary hydraulic system and the possible loss of aircraft direction control at critical air speeds, accomplish the following: PART I (a) PART I of this AD applies to airplanes which will be used for flight crew training. (b) Prior to further flight for crew training, and thereafter at intervals not to exceed 2,000 hours time in service from the last inspection, the airplane auxiliary hydraulic system must be inspected and replaced or reworked, as necessary, in accordance with the following: (1) Inspect for evidence of internal leakage per the information contained in Boeing Alert Service Bulletin 3154 dated April 12, 1974, or later FAA approved revisions of Boeing Alert Service Bulletin 3154 or by an equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region. (2) Airplanes with an auxiliary hydraulic system having internal leakage equal to or greater than 1.0 GPM but less than 3.0 GPM may not be used in training or revenue service but may only be flown in accordance with FAR 21.197 to a maintenance base for replacement or rework, as necessary, of the defective auxiliary hydraulic system components. (3) Airplanes with an auxiliary hydraulic system having 3.0 GPM, or more, internal leakage must have the defective auxiliary hydraulic system components replaced or overhauled, as necessary, prior to further flight. PART II (a) PART II of this AD applies to airplanes which have not been inspected and reworked, as necessary, in accordance with Amendment 39-1753 (F. R. Doc. 73-25927), AD-73-25-2. (b) Within 300 hours time in service after the effective date of this AD, and thereafter at intervals not to exceed 2,000 hours time in service from the last inspection, accomplish the following: (1) Inspect for evidence of internal leakage and replace or rework, as necessary, per the information contained in Boeing Alert Service Bulletin 3154 dated April 12, 1974, or later FAA approved revisions of Boeing Alert Service Bulletin 3154 or by an equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region. (2) Airplanes with an auxiliary hydraulic system having internal leakage equal to or greater than 1.0 GPM but less than 3.0 GPM may not be used in revenue service but may only be flown in accordance with FAR 21.197 to a maintenance base for replacement or rework, as necessary, of the defective auxiliary hydraulic components. (3) Airplanes with an auxiliary hydraulic system having 3.0 GPM, or more, internal leakage must have the defective auxiliary hydraulic system components replaced or overhauled, as necessary, prior to further flight. PART III (a) PART III of this AD applies to airplanes which have been inspected and reworked, as necessary, in accordance with Amendment 39-1753 (F. R. Doc. 73-25927), AD-73-25-2. (b) Within 600 hours time in service after the effective date of this AD and thereafter at intervals not to exceed 2,000 hours time in service from the last inspection, accomplish the following: (1) Inspect for evidence of internal leakage and replace or rework, as necessary, per the information contained in Boeing Alert Service Bulletin 3154 dated April 12, 1974, or later FAA approved revisions of Boeing Alert Service Bulletin 3154, or by an equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region. (2) Airplanes with an auxiliary hydraulic system having internal leakage equal to or greater than 1.0 GPM but less than 3.0 GPM, may not be used in revenue service but may only be flown in accordance with FAR 21.197 to a maintenance base for replacement or rework, as necessary, of the defective auxiliary hydraulic system components. (3) Airplanes with an auxiliary hydraulic system having 3.0 GPM, or more, internal leakage must have the defective auxiliary hydraulic system components replaced or overhauled, as necessary, prior to further flight. For the purpose of complying with the repetitive periodic inspection requirement of this AD, the 2,000 hours time in service may be adjusted by submitting substantiating technical data through the FAA assigned maintenance inspector for the approval of the Chief, Engineering and Manufacturing Branch, Flight Standards Division, FAA, Northwest Region. This AD Amendment 39-1845 supersedes AD 73-25-2. This Amendment becomes effective May 14, 1974. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.