AD 46-13-03

final rule

LOCKHEED Model 18 Aircraft

AD Number
46-13-03
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft Lockheed Aircraft Corporation 18 LOCKHEED Model 18 Aircraft

Unsafe Condition

Hopper type oil tanks may have inadequate support at the sump and insufficient oil reservoir for propeller feathering, leading to oil starvation and engine failure.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Inspect oil tanks to determine if they are hopper type. If retained, install a propeller feathering reserve oil tank (P/N 174399) and rework the hopper assembly with support assembly (P/N 174321). If removed, replace with conventional tank (P/N 73662) and install separate feathering line. Revise standpipe length or install new standpipe assembly as applicable.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

before next 10 hours of operation

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Lockheed Model 18 Aircraft, Serial Numbers 2294 and up (except 2359, 2403, 2464, 2465) for some actions; all Series 18 except Models 18-07 and 18-40 with Serial Numbers 2293 and below, 2359, 2403, 2464, and 2465 for standpipe revisions.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

Hopper Oil Tanks

Applicability Source Text

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AD Final Rules - DRS_46-13-03.html
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AD Number:
46-13-03
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
LOCKHEED Model 18 Aircraft
Subject:
Hopper Oil Tanks
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
Make:
Lockheed Aircraft Corporation
Model:
18
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Superseded AD: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Superseded By: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: 46-13-03
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:  

AD NUMBER:   46-13-03

SUBJECT HEADING:   LOCKHEED Model 18 Aircraft

ACTION:  

SUMMARY:  

DATES:  

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
46-13-03 LOCKHEED: (Was Mandatory Note 6 of AD-723-2.) Applies to Model 18 Aircraft.

Compliance required before next 10 hours of operation.

The oil tanks should be examined to determine whether or not they are of the hopper type, and appropriate action in one of the following manners must be taken:

1. If a hopper type oil tank is installed and is to be retained in accordance with Note 14(b) of Aircraft Specification A-723-4 (for use with oil dilution), the following action must be taken (applies only to Serial Numbers 2294 and up):

(a) Install a propeller feathering reserve oil tank (P/N 174399) forward of the firewall. (Lockheed Service Bulletin No. 18/SB-115 dated April 18, 1945, covers this same subject.)

(b) Rework the hopper assembly to provide better support at the sump by installing a new support assembly (P/N 174321). At each engine change, remove plate and elbow on bottom of sump housing (P/N 114690) and inspect hopper with a light and mirror. (Lockheed Service Bulletin No. 18-99 dated September 29, 1943, covers this same subject.)

2. If the hopper type oil tank is to be removed, the following action must be taken (applies only to Serial Numbers 2294 and up, except Serial Numbers 2359, 2403, 2464, and 2465):

Remove the hopper type oil tank and propeller feathering lines and replace with a conventional type tank (P/N 73662), fitted with a standpipe to provide a reservoir of oil for propeller feathering, and install a separate feathering line from the oil tank to the feathering pump. (Lockheed Service Bulletin No. 18-100 dated March 3, 1944, covers this same subject.)

3. On airplanes which have conventional oil tanks other than P/N 73662, the standpipe at the outlet in each tank must be revised in one of the following manners, whichever is applicable. (Applies to all Series 18 airplanes, except Models 18-07 and 18-40, with Serial Numbers 2293 and below, 2359, 2403, 2464, and 2465.)

(a) If the tanks are equipped with the standard 3 31/32-inch long standpipes (P/N 164101), the standpipe in each tank should be removed and a new 4 15/16-inch standpipe (P/N 16401, change D) installed.

b) If the tanks are equipped with oil stick gage foam guards, the existing standpipe in each tank should be cut off near the bottom of the tank, the foam guard cut off approximately 5.38 inches from the bottom surface of the oil tank outlet connection boss, and a new standpipe assembly (P/N 173806) installed.

(Lockheed Service Bulletin No. 18-105 dated October 19, 1943, covers this same subject.)

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_46-13-03.html
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Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
46-13-03
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
LOCKHEED Model 18 Aircraft
Subject:
Hopper Oil Tanks
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
Make:
Lockheed Aircraft Corporation
Model:
18
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: 46-13-03
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:  

AD NUMBER:   46-13-03

SUBJECT HEADING:   LOCKHEED Model 18 Aircraft

ACTION:  

SUMMARY:  

DATES:  

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
46-13-03 LOCKHEED: (Was Mandatory Note 6 of AD-723-2.) Applies to Model 18 Aircraft.

Compliance required before next 10 hours of operation.

The oil tanks should be examined to determine whether or not they are of the hopper type, and appropriate action in one of the following manners must be taken:

1. If a hopper type oil tank is installed and is to be retained in accordance with Note 14(b) of Aircraft Specification A-723-4 (for use with oil dilution), the following action must be taken (applies only to Serial Numbers 2294 and up):

(a) Install a propeller feathering reserve oil tank (P/N 174399) forward of the firewall. (Lockheed Service Bulletin No. 18/SB-115 dated April 18, 1945, covers this same subject.)

(b) Rework the hopper assembly to provide better support at the sump by installing a new support assembly (P/N 174321). At each engine change, remove plate and elbow on bottom of sump housing (P/N 114690) and inspect hopper with a light and mirror. (Lockheed Service Bulletin No. 18-99 dated September 29, 1943, covers this same subject.)

2. If the hopper type oil tank is to be removed, the following action must be taken (applies only to Serial Numbers 2294 and up, except Serial Numbers 2359, 2403, 2464, and 2465):

Remove the hopper type oil tank and propeller feathering lines and replace with a conventional type tank (P/N 73662), fitted with a standpipe to provide a reservoir of oil for propeller feathering, and install a separate feathering line from the oil tank to the feathering pump. (Lockheed Service Bulletin No. 18-100 dated March 3, 1944, covers this same subject.)

3. On airplanes which have conventional oil tanks other than P/N 73662, the standpipe at the outlet in each tank must be revised in one of the following manners, whichever is applicable. (Applies to all Series 18 airplanes, except Models 18-07 and 18-40, with Serial Numbers 2293 and below, 2359, 2403, 2464, and 2465.)

(a) If the tanks are equipped with the standard 3 31/32-inch long standpipes (P/N 164101), the standpipe in each tank should be removed and a new 4 15/16-inch standpipe (P/N 16401, change D) installed.

b) If the tanks are equipped with oil stick gage foam guards, the existing standpipe in each tank should be cut off near the bottom of the tank, the foam guard cut off approximately 5.38 inches from the bottom surface of the oil tank outlet connection boss, and a new standpipe assembly (P/N 173806) installed.

(Lockheed Service Bulletin No. 18-105 dated October 19, 1943, covers this same subject.)

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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