AD 89-14-03

final rule

LOCKHEED AERONAUTICAL SYSTEMS COMPANY Models L-188A and L-188C Series Airplanes

AD Number
89-14-03
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft Lockheed Martin Corporation 188A LOCKHEED AERONAUTICAL SYSTEMS COMPANY Models L-188A and L-188C Series Airplanes
aircraft Lockheed Martin Corporation 188C LOCKHEED AERONAUTICAL SYSTEMS COMPANY Models L-188A and L-188C Series Airplanes

Unsafe Condition

Flap asymmetry due to spline disengagement of flap universal joints without a stop could cause airplane control difficulties.

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

Required Actions

Inspect flap universal joints within 90 days to determine if they are splined without a stop. Remove affected joints and install splined joints with a stop, or modify joints by adding a snap ring or pins. Verify torque tube engagement and distances, inspect shutoff valves for hang-up or slow response, rewire the flap asymmetry annunciator light, and comply with repetitive inspections at intervals not exceeding one year.

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

Compliance Time

Within 90 days after the effective date of this AD and thereafter at intervals not to exceed one year

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

Affected Aircraft

Lockheed Model L-188A and L-188C series airplanes, certificated in any category.

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

Federal Register Abstract

Flap Universal Joints

Applicability Source Text

Show captured applicability text from the source AD
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AD Number:
89-14-03
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
LOCKHEED AERONAUTICAL SYSTEMS COMPANY Models L-188A and L-188C Series Airplanes
Subject:
Flap Universal Joints
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
07/24/1989
Make:
Lockheed Martin Corporation
Model:
188A | 188C
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Superseded AD: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Superseded By: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: 89-14-03
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-6243

AD NUMBER:   89-14-03

SUBJECT HEADING:   LOCKHEED AERONAUTICAL SYSTEMS COMPANY Models L-188A and L-188C Series Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective on July 24, 1989.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
89-14-03 LOCKHEED AERONAUTICAL SYSTEMS COMPANY: Amendment 39-6243.

Applicability: Lockheed Model L-188A and L-188C series airplanes, certificated in any category.

Compliance: Required as indicated, unless previously accomplished.

To prevent airplane control difficulties due to flap asymmetry, accomplish the following:

A. Within 90 days after the effective date of this AD, inspect the flap universal joints to determine if they are splined without a stop.

NOTE: Flap universal joints that are splined without a stop are easily detected by the lack of a screw and washer that holds the pins in place. If they do not have a stop, accomplish the following:

1. Remove from service any flap universal joints that are splined without a stop and install universal joints that are splined with a stop; or

2. Cut a circumferential groove in the splines of the torque tube shafts on each side of the universal joints (1 inch from the end of the shaft) and install a snap ring, in a manner approved by the Manager, Los Angeles Aircraft Certification Office, Northwest Mountain Region. The snap ring is to eliminate the possibility of spline disengagement. The snap ring should completely encircle the shaft; or

3. Modify each universal joint by drilling a hole and installing a 1/8-inch diameter steel pin through each side (two per joint). Locate the pin from .7 to .8-inch from each end, and locate so as to intersect the spline centerline. Peen both pin ends. This modification must be accomplished in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office, Northwest Mountain Region.

NOTE: Local spotfacing may be necessary on pins located at maximum dimension.

B. Within 90 days after the effective date of this AD and thereafter at intervals not to exceed one year, verify proper torque tube-to-universal joint engagement of .375-inch, as specified in Detail E of the L-188 Maintenance Manual, Section 27-6-8, Figure 201; and verify that the distance between the edges of the torque tube shoulders at BL55 is 5.5 to 5.87 inches (universal joints with internal stop), or 6.0 to 6.6 inches for universal joints reworked with added stop pins.

C. Within 90 days after the effective date of this AD and thereafter at intervals not to exceed one year, inspect the wing flap asymmetry shutoff valves, P/N 668225-1, to ascertain whether the valves hang up or respond slowly (greater than 1 second).

1. If the valves hang up or respond slowly, prior to further flight, install a functioning serviceable valve of the same part number (P/N 668225-1) and repeat the inspections at intervals not to exceed one year.

2. Installation of modified valve, P/N 668225-101, or a new valve P/N 668225-101, in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office, Northwest Mountain Region, constitutes terminating action for the repetitive inspections of the wing flap asymmetry shutoff valves required by paragraph C. and C.1., above.

D. Within 90 days after the effective date of this AD, rewire the flap asymmetry annunciator light in the cockpit to trigger the annunciator, in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office, Northwest Mountain Region, so that the light in the cockpit will illuminate when the asymmetry detector is tripped and not be dependent on the shutoff valve.

E. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region.

NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment and then send it to the Manager, Los Angeles Aircraft Certification Office.

F. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a base to accomplish the actions required by this AD.

All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Lockheed Aeronautical Systems Company, P.O. Box 551, Burbank, California 91520, Attn: L-188 Commercial Support Contracts, Dept. 63-11, Unit 33. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or 3229 East Spring Street, Long Beach, California.

This amendment (39-6243, AD 89-14-03) becomes effective on July 24, 1989.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_89-14-03.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
89-14-03
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
LOCKHEED AERONAUTICAL SYSTEMS COMPANY Models L-188A and L-188C Series Airplanes
Subject:
Flap Universal Joints
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
07/24/1989
Make:
Lockheed Martin Corporation
Model:
188A | 188C
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: 89-14-03
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-6243

AD NUMBER:   89-14-03

SUBJECT HEADING:   LOCKHEED AERONAUTICAL SYSTEMS COMPANY Models L-188A and L-188C Series Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective on July 24, 1989.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
89-14-03 LOCKHEED AERONAUTICAL SYSTEMS COMPANY: Amendment 39-6243.

Applicability: Lockheed Model L-188A and L-188C series airplanes, certificated in any category.

Compliance: Required as indicated, unless previously accomplished.

To prevent airplane control difficulties due to flap asymmetry, accomplish the following:

A. Within 90 days after the effective date of this AD, inspect the flap universal joints to determine if they are splined without a stop.

NOTE: Flap universal joints that are splined without a stop are easily detected by the lack of a screw and washer that holds the pins in place. If they do not have a stop, accomplish the following:

1. Remove from service any flap universal joints that are splined without a stop and install universal joints that are splined with a stop; or

2. Cut a circumferential groove in the splines of the torque tube shafts on each side of the universal joints (1 inch from the end of the shaft) and install a snap ring, in a manner approved by the Manager, Los Angeles Aircraft Certification Office, Northwest Mountain Region. The snap ring is to eliminate the possibility of spline disengagement. The snap ring should completely encircle the shaft; or

3. Modify each universal joint by drilling a hole and installing a 1/8-inch diameter steel pin through each side (two per joint). Locate the pin from .7 to .8-inch from each end, and locate so as to intersect the spline centerline. Peen both pin ends. This modification must be accomplished in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office, Northwest Mountain Region.

NOTE: Local spotfacing may be necessary on pins located at maximum dimension.

B. Within 90 days after the effective date of this AD and thereafter at intervals not to exceed one year, verify proper torque tube-to-universal joint engagement of .375-inch, as specified in Detail E of the L-188 Maintenance Manual, Section 27-6-8, Figure 201; and verify that the distance between the edges of the torque tube shoulders at BL55 is 5.5 to 5.87 inches (universal joints with internal stop), or 6.0 to 6.6 inches for universal joints reworked with added stop pins.

C. Within 90 days after the effective date of this AD and thereafter at intervals not to exceed one year, inspect the wing flap asymmetry shutoff valves, P/N 668225-1, to ascertain whether the valves hang up or respond slowly (greater than 1 second).

1. If the valves hang up or respond slowly, prior to further flight, install a functioning serviceable valve of the same part number (P/N 668225-1) and repeat the inspections at intervals not to exceed one year.

2. Installation of modified valve, P/N 668225-101, or a new valve P/N 668225-101, in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office, Northwest Mountain Region, constitutes terminating action for the repetitive inspections of the wing flap asymmetry shutoff valves required by paragraph C. and C.1., above.

D. Within 90 days after the effective date of this AD, rewire the flap asymmetry annunciator light in the cockpit to trigger the annunciator, in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office, Northwest Mountain Region, so that the light in the cockpit will illuminate when the asymmetry detector is tripped and not be dependent on the shutoff valve.

E. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region.

NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment and then send it to the Manager, Los Angeles Aircraft Certification Office.

F. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a base to accomplish the actions required by this AD.

All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Lockheed Aeronautical Systems Company, P.O. Box 551, Burbank, California 91520, Attn: L-188 Commercial Support Contracts, Dept. 63-11, Unit 33. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or 3229 East Spring Street, Long Beach, California.

This amendment (39-6243, AD 89-14-03) becomes effective on July 24, 1989.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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