AD 91-18-06
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Vickers-Armstrongs (Aircraft Limited) | Viscount 744 | Airworthiness Directives; BRITISH AEROSPACE Viscount Model 744, 745D, and 810 Series Airplanes |
| aircraft | Vickers-Armstrongs (Aircraft Limited) | Viscount 745D | Airworthiness Directives; BRITISH AEROSPACE Viscount Model 744, 745D, and 810 Series Airplanes |
| aircraft | Vickers-Armstrongs (Aircraft Limited) | Viscount 810 | Airworthiness Directives; BRITISH AEROSPACE Viscount Model 744, 745D, and 810 Series Airplanes |
Unsafe Condition
Cracks in the wing flap guide rails and corrosion at the abutment face of flap guide rails and flap end ribs on landing flaps could reduce structural integrity of the landing flaps.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Perform non-destructive testing (NDT) inspections within 180 days after the effective date or prior to 500 landings after the effective date, whichever comes first, and thereafter every 360 days. Repairs for cracks or excessive corrosion must be approved by the FAA's Standardization Branch. Corrosion repairs require removal of guide rails, visual confirmation, rework, and reprotection as per specified PTLs, including dye penetrant inspection post-blending.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 180 days after the effective date of this AD, or prior to the accumulation of 500 landings after the effective date, whichever occurs first, and thereafter at intervals not to exceed 360 days
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
All Viscount Model 744, 745D, and 810 series airplanes, certificated in any category.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Inspect Wing Flap Guide Rails
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-18-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-18-06 Document Type: AD Final Rules Docket Number: 91-NM-81-AD Subject Heading: Airworthiness Directives; BRITISH AEROSPACE Viscount Model 744, 745D, and 810 Series Airplanes Subject: Inspect Wing Flap Guide Rails Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/23/1991 Make: Vickers-Armstrongs (Aircraft Limited) Model: Viscount 744 | Viscount 745D | Viscount 810 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: 91-18-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-NM-81-AD AMENDMENT: 39-8009 AD NUMBER: 91-18-06 SUBJECT HEADING: Airworthiness Directives; BRITISH AEROSPACE Viscount Model 744, 745D, and 810 Series Airplanes ACTION: SUMMARY: DATES: Effective September 23, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-18-06 BRITISH AEROSPACE: Amendment 39-8009. Docket No. 91-NM-81-AD. Applicability: All Viscount Model 744, 745D, and 810 series airplanes, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent reduced structural integrity of the landing flaps, accomplish the following: (a) Within 180 days after the effective date of this AD, or prior to the accumulation of 500 landings after the effective date of this AD, whichever occurs first, and thereafter at intervals not to exceed 360 days, perform non-destructive testing (NDT) inspections to detect cracks in the wing flap guide rails, and to detect corrosion at the abutment face of flap guide rails and flap end ribs on all landing flaps on the left and right wings, in accordance with British Aerospace Preliminary Technical Leaflet (PTL) No. 301, Issue 2, dated November 2, 1989, or PTL No. 170, Issue 2, dated November 2, 1989, as applicable. (b) If cracks are found, prior to further flight, repair in a manner approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. (c) If corrosion is found, prior to further flight, remove the guide rail from the landing flap end rib for visual confirmation, rectification rework, and reprotection of both the guide rail and flap end rib abutment surfaces in accordance with paragraph 2.3.1 of British Aerospace Preliminary Technical Leaflet (PTL) No. 301, Issue 2, dated November 2, 1989, or PTL No. 170, Issue 2, dated November 2, 1989, as applicable. (1) Local corroded areas must be blended out to a maximum depth of 0.06 inch. The blended areas should extend beyond the corroded area by a minimum of 0.2 inch where the depth of corrosion is less than 0.03 inch, and a minimum of 0.3 inch where the depth of corrosion is greater than 0.03 inch, but must not exceed 70 percent of the local abutment face width. (2) Following blending, perform a dye penetrant inspection of the abutment surfaces to ensure that all traces of corrosion have been removed. (3) Following repair, and prior to reinstallation of the guide rail, apply protective treatment in accordance with paragraph 2.5 of the appropriate PTL. (4) If corrosion found is in excess of the limitations specified in the appropriate PTL, prior to further flight, repair in a manner approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. (d) An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Standardization Branch, ANM-113. (e) 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. (f) The inspection and repair requirements shall be done in accordance with British Aerospace Preliminary Technical Leaflet (PTL) No. 301, Issue 2, dated November 2, 1989, or PTL No. 170, Issue 2, dated November 2, 1989. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from British Aerospace, PLC, Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington, D.C. Copies may be inspected at the FAA, Transport Airplane Directorate, Renton, Washington; or at the Office of the Federal Register, 1100 L Street N.W., Room 8401, Washington, D.C. This amendment (39-8009, AD 91-18-06) becomes effective on September 23, 1991. FOOTER:
Document Text
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AD Final Rules - DRS_91-18-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-18-06 Document Type: AD Final Rules Docket Number: 91-NM-81-AD Subject Heading: Airworthiness Directives; BRITISH AEROSPACE Viscount Model 744, 745D, and 810 Series Airplanes Subject: Inspect Wing Flap Guide Rails Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/23/1991 Make: Vickers-Armstrongs (Aircraft Limited) Model: Viscount 744 | Viscount 745D | Viscount 810 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: 91-18-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-NM-81-AD AMENDMENT: 39-8009 AD NUMBER: 91-18-06 SUBJECT HEADING: Airworthiness Directives; BRITISH AEROSPACE Viscount Model 744, 745D, and 810 Series Airplanes ACTION: SUMMARY: DATES: Effective September 23, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-18-06 BRITISH AEROSPACE: Amendment 39-8009. Docket No. 91-NM-81-AD. Applicability: All Viscount Model 744, 745D, and 810 series airplanes, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent reduced structural integrity of the landing flaps, accomplish the following: (a) Within 180 days after the effective date of this AD, or prior to the accumulation of 500 landings after the effective date of this AD, whichever occurs first, and thereafter at intervals not to exceed 360 days, perform non-destructive testing (NDT) inspections to detect cracks in the wing flap guide rails, and to detect corrosion at the abutment face of flap guide rails and flap end ribs on all landing flaps on the left and right wings, in accordance with British Aerospace Preliminary Technical Leaflet (PTL) No. 301, Issue 2, dated November 2, 1989, or PTL No. 170, Issue 2, dated November 2, 1989, as applicable. (b) If cracks are found, prior to further flight, repair in a manner approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. (c) If corrosion is found, prior to further flight, remove the guide rail from the landing flap end rib for visual confirmation, rectification rework, and reprotection of both the guide rail and flap end rib abutment surfaces in accordance with paragraph 2.3.1 of British Aerospace Preliminary Technical Leaflet (PTL) No. 301, Issue 2, dated November 2, 1989, or PTL No. 170, Issue 2, dated November 2, 1989, as applicable. (1) Local corroded areas must be blended out to a maximum depth of 0.06 inch. The blended areas should extend beyond the corroded area by a minimum of 0.2 inch where the depth of corrosion is less than 0.03 inch, and a minimum of 0.3 inch where the depth of corrosion is greater than 0.03 inch, but must not exceed 70 percent of the local abutment face width. (2) Following blending, perform a dye penetrant inspection of the abutment surfaces to ensure that all traces of corrosion have been removed. (3) Following repair, and prior to reinstallation of the guide rail, apply protective treatment in accordance with paragraph 2.5 of the appropriate PTL. (4) If corrosion found is in excess of the limitations specified in the appropriate PTL, prior to further flight, repair in a manner approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. (d) An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Standardization Branch, ANM-113. (e) 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. (f) The inspection and repair requirements shall be done in accordance with British Aerospace Preliminary Technical Leaflet (PTL) No. 301, Issue 2, dated November 2, 1989, or PTL No. 170, Issue 2, dated November 2, 1989. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from British Aerospace, PLC, Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington, D.C. Copies may be inspected at the FAA, Transport Airplane Directorate, Renton, Washington; or at the Office of the Federal Register, 1100 L Street N.W., Room 8401, Washington, D.C. This amendment (39-8009, AD 91-18-06) becomes effective on September 23, 1991. FOOTER:
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