AD 91-23-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Fokker | F-28 | Airworthiness Directives; FOKKER Model F-28 Series Airplanes |
Unsafe Condition
Cracks in the horizontal stabilizer attach fittings could cause uncommanded movement of the horizontal stabilizer and subsequent reduced controllability of the airplane.
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Required Actions
Perform a high-frequency eddy current inspection of the horizontal stabilizer attach fittings within 90 days after the effective date of this AD, following Fokker Service Bulletin F28/55-28. If cracks are found, repair or replace the affected fittings with a serviceable part before further flight. Compliance may be adjusted with FAA approval.
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Compliance Time
within 90 days after the effective date of this AD
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Affected Aircraft
Fokker Model F-28 series airplanes listed in Fokker Service Bulletin F28/55-28, dated December 21, 1990
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Federal Register Abstract
Horizontal Stabilizer Attach Fittings
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-23-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-23-06 Document Type: AD Final Rules Docket Number: 91-NM-58-AD Subject Heading: Airworthiness Directives; FOKKER Model F-28 Series Airplanes Subject: Horizontal Stabilizer Attach Fittings Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/17/1991 Make: Model: F.28 Mark 0100 | F.28 Mark 1000 | F.28 Mark 2000 | F.28 Mark 3000 | F.28 Mark 4000 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 91-23-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-NM-58-AD AMENDMENT: 39-8075 AD NUMBER: 91-23-06 SUBJECT HEADING: Airworthiness Directives; FOKKER Model F-28 Series Airplanes ACTION: SUMMARY: DATES: Effective December 17, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-23-06 FOKKER: Amendment 39-8075. Docket No. 91-NM-58-AD. Applicability: Model F-28 series airplanes, as listed in Fokker Service Bulletin F28/55-28, dated December 21, 1990, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent uncommanded movement of the horizontal stabilizer and subsequent reduced controllability of the airplane, accomplish the following: A. Within 90 days after the effective date of this AD, perform a high-frequency eddy current inspection to detect cracks in the horizontal stabilizer attach fittings, in accordance with Parts 1 and 2 of Fokker Service Bulletin F28/55-28, dated December 21, 1990. If cracks are found, prior to further flight, repair or replace affected attach fitting with a serviceable part, in accordance with Part 3 of the service bulletin. B. 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. C. 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. D. The inspection, repair, and replacement requirements shall be done in accordance with Fokker Service Bulletin F28/55-28, dated December 21, 1990. 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 Fokker Aircraft USA, Inc., 1199 North Fairfax Street, Alexandria, Virginia 22314. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, S.W., Renton, Washington; or at the Office of the Federal Register, 1100 L Street N.W., Room 8401, Washington, D.C. This amendment (39-8075, AD 91-23-06) becomes effective on December 17, 1991. FOOTER:
Document Text
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AD Final Rules - DRS_91-23-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-23-06 Document Type: AD Final Rules Docket Number: 91-NM-58-AD Subject Heading: Airworthiness Directives; FOKKER Model F-28 Series Airplanes Subject: Horizontal Stabilizer Attach Fittings Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/17/1991 Make: Model: F.28 Mark 0100 | F.28 Mark 1000 | F.28 Mark 2000 | F.28 Mark 3000 | F.28 Mark 4000 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: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 91-23-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-NM-58-AD AMENDMENT: 39-8075 AD NUMBER: 91-23-06 SUBJECT HEADING: Airworthiness Directives; FOKKER Model F-28 Series Airplanes ACTION: SUMMARY: DATES: Effective December 17, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-23-06 FOKKER: Amendment 39-8075. Docket No. 91-NM-58-AD. Applicability: Model F-28 series airplanes, as listed in Fokker Service Bulletin F28/55-28, dated December 21, 1990, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent uncommanded movement of the horizontal stabilizer and subsequent reduced controllability of the airplane, accomplish the following: A. Within 90 days after the effective date of this AD, perform a high-frequency eddy current inspection to detect cracks in the horizontal stabilizer attach fittings, in accordance with Parts 1 and 2 of Fokker Service Bulletin F28/55-28, dated December 21, 1990. If cracks are found, prior to further flight, repair or replace affected attach fitting with a serviceable part, in accordance with Part 3 of the service bulletin. B. 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. C. 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. D. The inspection, repair, and replacement requirements shall be done in accordance with Fokker Service Bulletin F28/55-28, dated December 21, 1990. 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 Fokker Aircraft USA, Inc., 1199 North Fairfax Street, Alexandria, Virginia 22314. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, S.W., Renton, Washington; or at the Office of the Federal Register, 1100 L Street N.W., Room 8401, Washington, D.C. This amendment (39-8075, AD 91-23-06) becomes effective on December 17, 1991. FOOTER:
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Retrieved: Apr 8, 2026
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