AD 87-03-12
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Viking Air Limited | DHC-6-1 | Airworthiness Directives; DeHavilland Models DHC-6 1, 100, 200, and 300 Series Airplanes |
| aircraft | Viking Air Limited | DHC-6-100 | Airworthiness Directives; DeHavilland Models DHC-6 1, 100, 200, and 300 Series Airplanes |
| aircraft | Viking Air Limited | DHC-6-200 | Airworthiness Directives; DeHavilland Models DHC-6 1, 100, 200, and 300 Series Airplanes |
| aircraft | Viking Air Limited | DHC-6-300 | Airworthiness Directives; DeHavilland Models DHC-6 1, 100, 200, and 300 Series Airplanes |
Unsafe Condition
Disengagement of the utility seat forward legs from the floor mounting rail.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Within 50 hours time-in-service after the effective date, inspect the lower end of each forward leg by attempting to move it sideways into the keyhole slot using hand force. If removable, remove the seat from service until Modification No. 6/1828 is incorporated per Service Bulletin 6/447, Rev C. Repeat checks each time seats are moved from stowed to deployed position, which can be done by a flightcrew member briefed on the procedure. Equivalent compliance may be approved by the FAA.
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Compliance Time
Within 50 hours time-in-service after the effective date, unless already accomplished within the last 25 hours time-in-service, and at subsequent intervals not to exceed 50 hours time-in-service thereafter.
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Affected Aircraft
DeHavilland Models DHC-6 1, 100, 200, and 300 Series airplanes certificated in any category, when fitted with side folding cabin utility seats.
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Federal Register Abstract
Utility Seat - Forward Legs
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_87-03-12.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 87-03-12 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DeHavilland Models DHC-6 1, 100, 200, and 300 Series Airplanes Subject: Utility Seat - Forward Legs Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/13/1987 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: 87-03-12 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5549 AD NUMBER: 87-03-12 SUBJECT HEADING: Airworthiness Directives; DeHavilland Models DHC-6 1, 100, 200, and 300 Series Airplanes ACTION: SUMMARY: DATES: Effective February 13, 1987. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 87-03-12 DEHAVILLAND: Amendment 39-5549. Applies to DHC-6 Models 1, 100, 200, and 300 airplanes certificated in any category, when fitted with side folding cabin utility seats. Compliance: Required as indicated, unless already accomplished. To prevent disengagement of the utility seat forward legs from the floor mounting rail, accomplish the following: (a) Within 50 hours time-in-service (TIS) after the effective date of this AD, unless already accomplished within the last 25 hours TIS, and at subsequent intervals not to exceed 50 hours TIS thereafter, attempt to move the lower end of each forward leg sideways into the open part of the keyhole slot using as much force as can be exerted by hand. If the leg can be removed from the keyhole slot, remove the seat from service until Modification No. 6/1828 is incorporated in accordance with the ACCOMPLISHMENT INSTRUCTIONS of DeHavilland Service Bulletin (S/B) No. 6/447, Revision C, dated May 16, 1986. (b) Repeat the check in paragraph (a) of this AD each time the seats are moved from stowed to deployed position. (c) The check required by paragraph (b) of this AD may be accomplished by a flightcrew member, certificated under FAR 61 or FAR 63 rules, briefed on the procedure. (d) When Modification No. 6/1828 is incorporated in accordance with the ACCOMPLISHMENT INSTRUCTIONS of DeHavilland S/B No. 6/447, Revision C, on each seat, subsequent checks required by this AD are no longer required on that seat. (e) An equivalent means of compliance may be used when approved by the Manager, New York Aircraft Certification Office, Federal Aviation Administration, ANE-170, 181 South Franklin Avenue, Room 202, Valley Stream, New York 11581. This AD supersedes AD 84-07-07, Amendment 39-4841. This amendment becomes effective on February 13, 1987. FOOTER:
Document Text
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AD Final Rules - DRS_87-03-12.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 87-03-12 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DeHavilland Models DHC-6 1, 100, 200, and 300 Series Airplanes Subject: Utility Seat - Forward Legs Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/13/1987 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: 87-03-12 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5549 AD NUMBER: 87-03-12 SUBJECT HEADING: Airworthiness Directives; DeHavilland Models DHC-6 1, 100, 200, and 300 Series Airplanes ACTION: SUMMARY: DATES: Effective February 13, 1987. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 87-03-12 DEHAVILLAND: Amendment 39-5549. Applies to DHC-6 Models 1, 100, 200, and 300 airplanes certificated in any category, when fitted with side folding cabin utility seats. Compliance: Required as indicated, unless already accomplished. To prevent disengagement of the utility seat forward legs from the floor mounting rail, accomplish the following: (a) Within 50 hours time-in-service (TIS) after the effective date of this AD, unless already accomplished within the last 25 hours TIS, and at subsequent intervals not to exceed 50 hours TIS thereafter, attempt to move the lower end of each forward leg sideways into the open part of the keyhole slot using as much force as can be exerted by hand. If the leg can be removed from the keyhole slot, remove the seat from service until Modification No. 6/1828 is incorporated in accordance with the ACCOMPLISHMENT INSTRUCTIONS of DeHavilland Service Bulletin (S/B) No. 6/447, Revision C, dated May 16, 1986. (b) Repeat the check in paragraph (a) of this AD each time the seats are moved from stowed to deployed position. (c) The check required by paragraph (b) of this AD may be accomplished by a flightcrew member, certificated under FAR 61 or FAR 63 rules, briefed on the procedure. (d) When Modification No. 6/1828 is incorporated in accordance with the ACCOMPLISHMENT INSTRUCTIONS of DeHavilland S/B No. 6/447, Revision C, on each seat, subsequent checks required by this AD are no longer required on that seat. (e) An equivalent means of compliance may be used when approved by the Manager, New York Aircraft Certification Office, Federal Aviation Administration, ANE-170, 181 South Franklin Avenue, Room 202, Valley Stream, New York 11581. This AD supersedes AD 84-07-07, Amendment 39-4841. This amendment becomes effective on February 13, 1987. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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