AD 59-20-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Lockheed Martin Aeronautics Company | 1649A-98 | LOCKHEED Model 1649A Aircraft |
Unsafe Condition
Explosion of a wing tank due to the presence of an explosive mixture in the tanks.
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Required Actions
Remove static wicks on inboard wings adjacent to tank vents; install temporary placard at engineer's station specifying fuel usage restrictions; install P/N 634014-1 or equivalent flame arrestors in tank vent outlets. After flame arrestor installation, the placard requirement may be disregarded.
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Compliance Time
Compliance required on items (1) and (2) by October 15, 1959; compliance required on item (3) by December 1, 1959.
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Affected Aircraft
Lockheed Model 1649A Aircraft, all serial numbers.
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Federal Register Abstract
Fuel Use Placard and Flame Arrestors
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_59-20-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 59-20-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Model 1649A Aircraft Subject: Fuel Use Placard and Flame Arrestors Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Lockheed Martin Aeronautics Company Model: 1649A-98 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 59-20-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 59-20-02 SUBJECT HEADING: LOCKHEED Model 1649A Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 59-20-02 LOCKHEED: Applies to All Model 1649A Aircraft. Compliance required on items (1) and (2) by October 15, 1959; compliance required on item (3) by December 1, 1959. As a result of a recent accident involving a suspected explosion of a wing tank, the following shall be accomplished to prevent the possible recurrence of such an explosion: (1) Remove the static wick on the inboard wings adjacent to the tank vents. (2) Install temporary placard at engineer's station reading as follows: "In order to maintain a nonexplosive rich mixture in tanks, do not use fuel out of auxiliary tanks Nos. 5, 6, and 7 below 50 gallons. In operations which involve use of fuel from main tanks only, the 50 gallons of residual fuel in the auxiliary tanks must be replaced with 50 gallons of fresh fuel or mixed with at least 150 gallons of fresh fuel at the end of every 12 flight-hours or 5 flights, whichever occurs first." (3) Install P/N 634014-1 or equivalent flame arrestors in the tank vent outlets. After installation of flame arrestors described in item (3), item (2) may be disregarded. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_59-20-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 59-20-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED Model 1649A Aircraft Subject: Fuel Use Placard and Flame Arrestors Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Lockheed Martin Aeronautics Company Model: 1649A-98 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: 59-20-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 59-20-02 SUBJECT HEADING: LOCKHEED Model 1649A Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 59-20-02 LOCKHEED: Applies to All Model 1649A Aircraft. Compliance required on items (1) and (2) by October 15, 1959; compliance required on item (3) by December 1, 1959. As a result of a recent accident involving a suspected explosion of a wing tank, the following shall be accomplished to prevent the possible recurrence of such an explosion: (1) Remove the static wick on the inboard wings adjacent to the tank vents. (2) Install temporary placard at engineer's station reading as follows: "In order to maintain a nonexplosive rich mixture in tanks, do not use fuel out of auxiliary tanks Nos. 5, 6, and 7 below 50 gallons. In operations which involve use of fuel from main tanks only, the 50 gallons of residual fuel in the auxiliary tanks must be replaced with 50 gallons of fresh fuel or mixed with at least 150 gallons of fresh fuel at the end of every 12 flight-hours or 5 flights, whichever occurs first." (3) Install P/N 634014-1 or equivalent flame arrestors in the tank vent outlets. After installation of flame arrestors described in item (3), item (2) may be disregarded. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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