AD 70-24-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 747-100 Series | BOEING Model 747 Airplanes |
| aircraft | The Boeing Company | 747-100B Series | BOEING Model 747 Airplanes |
| aircraft | The Boeing Company | 747-100B SUD Series | BOEING Model 747 Airplanes |
| aircraft | The Boeing Company | 747-200B Series | BOEING Model 747 Airplanes |
| aircraft | The Boeing Company | 747-200C Series | BOEING Model 747 Airplanes |
| aircraft | The Boeing Company | 747-200F Series | BOEING Model 747 Airplanes |
| aircraft | The Boeing Company | 747-300 Series | BOEING Model 747 Airplanes |
| aircraft | The Boeing Company | 747-400 Series | BOEING Model 747 Airplanes |
| aircraft | The Boeing Company | 747-400D Series | BOEING Model 747 Airplanes |
| aircraft | The Boeing Company | 747-400F Series | BOEING Model 747 Airplanes |
| aircraft | The Boeing Company | 747SP Series | BOEING Model 747 Airplanes |
| aircraft | The Boeing Company | 747SR Series | BOEING Model 747 Airplanes |
Unsafe Condition
Loss of main landing gear wheels during airplane takeoff due to outboard bearing Timken Part No. LM 229139 with code letter 'A' through 'F'.
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Required Actions
Determine the coding identification of the outboard bearing Timken Part No. LM 229139 in all landing gear wheels. Replace any bearing with code letter 'A' through 'F' with a bearing with code letter 'G' or later or an equivalent bearing approved by the Chief, Aircraft Engineering Division, Western Region before further flight.
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Compliance Time
within the next 125 hours time in service after receipt of this telegram
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Affected Aircraft
Boeing 747-100 Series, 747-100B Series, 747-100B SUD Series, 747-200B Series, 747-200C Series, and other 747 models as listed in the AD.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Main Landing Gear Wheel Bearing
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_70-24-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 70-24-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Model 747 Airplanes Subject: Main Landing Gear Wheel Bearing Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/07/1971 Make: The Boeing Company Model: 747-100 Series | 747-100B Series | 747-100B SUD Series | 747-200B Series | 747-200C Series | 747-200...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: 70-24-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1203 AD NUMBER: 70-24-02 SUBJECT HEADING: BOEING Model 747 Airplanes ACTION: SUMMARY: DATES: Effective May 7, 1971. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 70-24-02 BOEING: Amdt. 39-1112 as amended by Amendment 39-1203. The following airworthiness directive, applicable to all operators of Boeing 747 airplanes, was effective immediately upon receipt of telegram dated November 5, 1970. Because of two cases of loss of main landings gear wheels during airplane takeoff, within the next 125 hours time in service after receipt of this telegram, unless already accomplished, determine the coding identification of the outboard bearing Timken Part No. LM 229139, in all landing gear wheels. Any bearing with code letter "A" through "F" must be replaced with a bearing with code letter "G" "or later" or with an equivalent bearing approved by the Chief, Aircraft Engineering Division, Western Region, before further flight. NOTE: The bearing identification code letter is between the words "Timken" and "made" on the back face of the bearing cone. Amendment 39-1112 became effective upon publication in the Federal Register for all persons except those to whom it was made effective immediately by telegram dated November 5, 1970. This Amendment 39-1203 becomes effective May 7, 1971. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_70-24-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 70-24-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Model 747 Airplanes Subject: Main Landing Gear Wheel Bearing Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/07/1971 Make: The Boeing Company Model: 747-100 Series | 747-100B Series | 747-100B SUD Series | 747-200B Series | 747-200C Series | 747-200...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: 70-24-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1203 AD NUMBER: 70-24-02 SUBJECT HEADING: BOEING Model 747 Airplanes ACTION: SUMMARY: DATES: Effective May 7, 1971. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 70-24-02 BOEING: Amdt. 39-1112 as amended by Amendment 39-1203. The following airworthiness directive, applicable to all operators of Boeing 747 airplanes, was effective immediately upon receipt of telegram dated November 5, 1970. Because of two cases of loss of main landings gear wheels during airplane takeoff, within the next 125 hours time in service after receipt of this telegram, unless already accomplished, determine the coding identification of the outboard bearing Timken Part No. LM 229139, in all landing gear wheels. Any bearing with code letter "A" through "F" must be replaced with a bearing with code letter "G" "or later" or with an equivalent bearing approved by the Chief, Aircraft Engineering Division, Western Region, before further flight. NOTE: The bearing identification code letter is between the words "Timken" and "made" on the back face of the bearing cone. Amendment 39-1112 became effective upon publication in the Federal Register for all persons except those to whom it was made effective immediately by telegram dated November 5, 1970. This Amendment 39-1203 becomes effective May 7, 1971. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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