AD 67-33-02

final rule

Airworthiness Directives; de Havilland Aircraft Type DHC-6 Series Aircraft

AD Number
67-33-02
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
Federal Register: December 30, 1967
Technical illustration of an aircraft flight control surface and actuator
Problem area Flight controls

Applicability

TypeManufacturerModelDetails
aircraft Viking Air Limited DHC-6-1 Airworthiness Directives; de Havilland Aircraft Type DHC-6 Series Aircraft
aircraft Viking Air Limited DHC-6-100 Airworthiness Directives; de Havilland Aircraft Type DHC-6 Series Aircraft
aircraft Viking Air Limited DHC-6-200 Airworthiness Directives; de Havilland Aircraft Type DHC-6 Series Aircraft
aircraft Viking Air Limited DHC-6-300 Airworthiness Directives; de Havilland Aircraft Type DHC-6 Series Aircraft

Unsafe Condition

Flutter of the left elevator trim tab

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

Required Actions

Install a placard stating 'SPEED SHALL NOT EXCEED 125 KNOTS IAS (144 M.P.H. IAS)' before next flight. Conduct one-time inspections on the left elevator-trim tab assembly including bolt removal, trim tab operation, and vertical free play measurement. Visually inspect the trim tab for diagonal buckling or concavity before each flight. Replace non-compliant trim tabs with approved parts. Discontinue inspections after approved modification.

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

Compliance Time

Prior to the next flight, before each flight

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

Affected Aircraft

Viking Air Limited DHC-6-1, DHC-6-100, DHC-6-200, DHC-6-300 aircraft

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

Federal Register Abstract

Left Elevator Trim Tab

Applicability Source Text

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AD Final Rules - DRS_67-33-02.html
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AD Number:
67-33-02
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; de Havilland Aircraft Type DHC-6 Series Aircraft
Subject:
Left Elevator Trim Tab
Status:
Current
Citation:
Federal Register: December 30, 1967
Citation Publish Date:
12/30/1967
Effective Date:
12/30/1967
Make:
Viking Air Limited
Model:
DHC-6-1 | DHC-6-100 | DHC-6-200 | DHC-6-300
Product Type:
Aircraft
Product Subtype:
Small 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: 67-33-02
CITATION:   [Federal Register: December 30, 1967]

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-532

AD NUMBER:   67-33-02

SUBJECT HEADING:   Airworthiness Directives; de Havilland Aircraft Type DHC-6 Series Aircraft

ACTION:  

SUMMARY:  

DATES:   Effective December 30, 1967.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
67-33-02 de HAVILLAND AIRCRAFT: Amdt. 39-532, Part 39, Federal Register December 30, 1967. Applies to Type DHC-6 Aircraft.

Due to flutter of the left elevator trim tab, accomplish the following after the effective date of this AD unless already accomplished.

(a) Prior to the next flight, install the following placard in full view of the pilot: "SPEED SHALL NOT EXCEED 125 KNOTS IAS (144 M.P.H. IAS)".

(b) Prior to the next flight, accomplish the following one-time inspections on the left elevator-trim tab assembly:

(1) Remove the bolt between the push rod and the tab operating lever and operate the trim tab control in the cockpit until the screw jack in the elevator is fully retracted. Lower the tab until the bolt can be inserted through the operating arm and the push rod without exerting pressure on the trim tab. If this can be accomplished, reconnect the tab to the push rod. If the holes do not align, adjust the push rod sufficiently to allow assembly without exerting pressure on the trim tab.

(2) With the trim tab in the neutral position, assure that the total vertical free play, measured adjacent to the operating lever, does not exceed one-tenth (0.1) inches at the trailing edge of the tab. Comply with this limit prior to further flight.

(c) Before each flight, visually inspect the left elevator trim tab top and bottom skins for diagonal buckling or concavity, other than the manufactured flutes. Trim tabs found to contain diagonal buckles or concavities must be replaced before further flight with a part of the same part number that has been inspected in accordance with this paragraph, or with an equivalent part approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. The repetitive inspection required by this paragraph also applies to replacement parts.

(d) The placard required by (a) may be removed, and the repetitive inspection required by (c) may be discontinued, when a trim tab modification, approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region, is incorporated.

(e) Upon request with substantiating data submitted through an FAA maintenance inspector, the compliance time specified in this AD may be increased by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region.

This amendment effective December 30, 1967, for all persons except those to whom it was made effective immediately by telegram dated December 1, 1967.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_67-33-02.html
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Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
67-33-02
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; de Havilland Aircraft Type DHC-6 Series Aircraft
Subject:
Left Elevator Trim Tab
Status:
Current
Citation:
Federal Register: December 30, 1967
Citation Publish Date:
12/30/1967
Effective Date:
12/30/1967
Make:
Viking Air Limited
Model:
DHC-6-1 | DHC-6-100 | DHC-6-200 | DHC-6-300
Product Type:
Aircraft
Product Subtype:
Small 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: 67-33-02
CITATION:   [Federal Register: December 30, 1967]

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-532

AD NUMBER:   67-33-02

SUBJECT HEADING:   Airworthiness Directives; de Havilland Aircraft Type DHC-6 Series Aircraft

ACTION:  

SUMMARY:  

DATES:   Effective December 30, 1967.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
67-33-02 de HAVILLAND AIRCRAFT: Amdt. 39-532, Part 39, Federal Register December 30, 1967. Applies to Type DHC-6 Aircraft.

Due to flutter of the left elevator trim tab, accomplish the following after the effective date of this AD unless already accomplished.

(a) Prior to the next flight, install the following placard in full view of the pilot: "SPEED SHALL NOT EXCEED 125 KNOTS IAS (144 M.P.H. IAS)".

(b) Prior to the next flight, accomplish the following one-time inspections on the left elevator-trim tab assembly:

(1) Remove the bolt between the push rod and the tab operating lever and operate the trim tab control in the cockpit until the screw jack in the elevator is fully retracted. Lower the tab until the bolt can be inserted through the operating arm and the push rod without exerting pressure on the trim tab. If this can be accomplished, reconnect the tab to the push rod. If the holes do not align, adjust the push rod sufficiently to allow assembly without exerting pressure on the trim tab.

(2) With the trim tab in the neutral position, assure that the total vertical free play, measured adjacent to the operating lever, does not exceed one-tenth (0.1) inches at the trailing edge of the tab. Comply with this limit prior to further flight.

(c) Before each flight, visually inspect the left elevator trim tab top and bottom skins for diagonal buckling or concavity, other than the manufactured flutes. Trim tabs found to contain diagonal buckles or concavities must be replaced before further flight with a part of the same part number that has been inspected in accordance with this paragraph, or with an equivalent part approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. The repetitive inspection required by this paragraph also applies to replacement parts.

(d) The placard required by (a) may be removed, and the repetitive inspection required by (c) may be discontinued, when a trim tab modification, approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region, is incorporated.

(e) Upon request with substantiating data submitted through an FAA maintenance inspector, the compliance time specified in this AD may be increased by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region.

This amendment effective December 30, 1967, for all persons except those to whom it was made effective immediately by telegram dated December 1, 1967.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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