AD 89-14-52

final rule

Airworthiness Directives; Boeing Model DHC-8 Series Airplanes

AD Number
89-14-52
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft Bombardier Inc. DHC-8-101 Airworthiness Directives; Boeing Model DHC-8 Series Airplanes
aircraft Bombardier Inc. DHC-8-102 Airworthiness Directives; Boeing Model DHC-8 Series Airplanes
aircraft Bombardier Inc. DHC-8-103 Airworthiness Directives; Boeing Model DHC-8 Series Airplanes
aircraft Bombardier Inc. DHC-8-106 Airworthiness Directives; Boeing Model DHC-8 Series Airplanes
aircraft Bombardier Inc. DHC-8-201 Airworthiness Directives; Boeing Model DHC-8 Series Airplanes
aircraft Bombardier Inc. DHC-8-202 Airworthiness Directives; Boeing Model DHC-8 Series Airplanes
aircraft Bombardier Inc. DHC-8-301 Airworthiness Directives; Boeing Model DHC-8 Series Airplanes
aircraft Bombardier Inc. DHC-8-311 Airworthiness Directives; Boeing Model DHC-8 Series Airplanes
aircraft Bombardier Inc. DHC-8-315 Airworthiness Directives; Boeing Model DHC-8 Series Airplanes

Unsafe Condition

Asymmetric flap deployment due to chafing damage/wear exceeding 0.010 inch in depth or 180 degrees of the circumference on flap drive primary torque tubes, and interference between cooling ducts and torque tubes.

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

Required Actions

Within 25 hours time-in-service after the effective date, visually inspect torque tubes for wear/damage and replace if exceeding limits; inspect cooling ducts for interference, reposition to provide 0.3 inch clearance, repair broken reinforcement wires and replace within 30 days; perform torque sensor operational check per Maintenance Program Task 2750/11. Submit findings report within 7 days. Alternate compliance may be approved.

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

Compliance Time

Within the next 25 hours time-in-service after the effective date of this AD

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

Affected Aircraft

De Havilland Model DHC-8 series airplanes, Serial Numbers 3 and subsequent

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

Federal Register Abstract

Flaps Torque Tubes

Applicability Source Text

Show captured applicability text from the source AD
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AD Number:
89-14-52
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; Boeing Model DHC-8 Series Airplanes
Subject:
Flaps Torque Tubes
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
08/21/1989
Make:
Bombardier Inc.
Model:
DHC-8-101 | DHC-8-102 | DHC-8-103 | DHC-8-106 | DHC-8-201 | DHC-8-202 | DHC-8-301 | DHC-8-311 | DHC-8-315
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: 89-14-52
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-6291

AD NUMBER:   89-14-52

SUBJECT HEADING:   Airworthiness Directives; Boeing Model DHC-8 Series Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective August 21, 1989

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:   89-14-52 BOEING OF CANADA, LTD., DE HAVILLAND DIVISION: Amendment 39- 6291. Final copy of telegraphic AD issued July 7, 1989.

Applicability: De Havilland Model DHC-8 series airplanes, Serial Numbers 3 and subsequent, certificated in any category.

Compliance: Required as indicated, unless previously accomplished.

To prevent asymmetric flap deployment, accomplish the following:

A. Within the next 25 hours time-in-service after the effective date of this AD:

1. Visually inspect the flap drive primary torque tubes in the vicinity of station YW 170 of the left and right wing where it enters the outboard side of each nacelle for signs of damage/wear due to chafing. Torque tubes must be replaced prior to further flight if wear exceeds either 0.010 inch in depth or 180 degrees of the circumference of the shafts.

2. Inspect cooling ducts (Part Number DSC 287-12-70/60) in the vicinity of station YW 170 of the left and right wing where it enters the outboard side of each nacelle for possible interference with the primary flap drive torque tube. Reposition cooling duct as necessary to provide a minimum clearance of 0.3 inch with the primary flap drive torque tube. If reinforcement wires of the cooling duct are broken due to chafing, the cooling duct must be repaired prior to further flight and replaced within 30 days.

3. Perform an operational check of the torque sensor, and take any indicated corrective actions, in accordance with Maintenance Program Task 2750/11. Refer to "Maintenance Program, Supplementary Information, PSM 1-8-7/1-83-7, Volume 2, Procedures - 27, Page 15, dated 15 July 1988."

B. Within 7 days after the completion of the inspections required by paragraph A., above, submit a report of findings, positive or negative, to the Manager, New York Aircraft Certification Office, ANE-170, FAA, New England Region, 181 South Franklin Avenue, Room 202, Valley Stream, New York, 11581. Reports must include the airplane serial number.

C. 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, New York Aircraft Certification Office, FAA, New England 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, New York Aircraft Certification Office.

D. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD.

These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or the New England Region, New York Aircraft Certification Office, 181 South Franklin Avenue, Room 202, Valley Stream, New York.

This amendment (39-6291, AD 89-14-52) becomes effective on August 21, 1989, as to all
persons except those persons to whom it was made immediately effective by telegraphic AD T89- 14-52, issued on July 7, 1989, which contained this amendment.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_89-14-52.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
89-14-52
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; Boeing Model DHC-8 Series Airplanes
Subject:
Flaps Torque Tubes
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
08/21/1989
Make:
Bombardier Inc.
Model:
DHC-8-101 | DHC-8-102 | DHC-8-103 | DHC-8-106 | DHC-8-201 | DHC-8-202 | DHC-8-301 | DHC-8-311 | DHC-8-315
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: 89-14-52
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-6291

AD NUMBER:   89-14-52

SUBJECT HEADING:   Airworthiness Directives; Boeing Model DHC-8 Series Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective August 21, 1989

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:   89-14-52 BOEING OF CANADA, LTD., DE HAVILLAND DIVISION: Amendment 39- 6291. Final copy of telegraphic AD issued July 7, 1989.

Applicability: De Havilland Model DHC-8 series airplanes, Serial Numbers 3 and subsequent, certificated in any category.

Compliance: Required as indicated, unless previously accomplished.

To prevent asymmetric flap deployment, accomplish the following:

A. Within the next 25 hours time-in-service after the effective date of this AD:

1. Visually inspect the flap drive primary torque tubes in the vicinity of station YW 170 of the left and right wing where it enters the outboard side of each nacelle for signs of damage/wear due to chafing. Torque tubes must be replaced prior to further flight if wear exceeds either 0.010 inch in depth or 180 degrees of the circumference of the shafts.

2. Inspect cooling ducts (Part Number DSC 287-12-70/60) in the vicinity of station YW 170 of the left and right wing where it enters the outboard side of each nacelle for possible interference with the primary flap drive torque tube. Reposition cooling duct as necessary to provide a minimum clearance of 0.3 inch with the primary flap drive torque tube. If reinforcement wires of the cooling duct are broken due to chafing, the cooling duct must be repaired prior to further flight and replaced within 30 days.

3. Perform an operational check of the torque sensor, and take any indicated corrective actions, in accordance with Maintenance Program Task 2750/11. Refer to "Maintenance Program, Supplementary Information, PSM 1-8-7/1-83-7, Volume 2, Procedures - 27, Page 15, dated 15 July 1988."

B. Within 7 days after the completion of the inspections required by paragraph A., above, submit a report of findings, positive or negative, to the Manager, New York Aircraft Certification Office, ANE-170, FAA, New England Region, 181 South Franklin Avenue, Room 202, Valley Stream, New York, 11581. Reports must include the airplane serial number.

C. 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, New York Aircraft Certification Office, FAA, New England 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, New York Aircraft Certification Office.

D. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD.

These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or the New England Region, New York Aircraft Certification Office, 181 South Franklin Avenue, Room 202, Valley Stream, New York.

This amendment (39-6291, AD 89-14-52) becomes effective on August 21, 1989, as to all
persons except those persons to whom it was made immediately effective by telegraphic AD T89- 14-52, issued on July 7, 1989, which contained this amendment.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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