AD 91-09-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | ATR - GIE Avions de Transport R gional | ATR42-300 | AEROSPATIALE Models ATR42-300 and ATR42-320 Series Airplanes |
| aircraft | ATR - GIE Avions de Transport R gional | ATR42-320 | AEROSPATIALE Models ATR42-300 and ATR42-320 Series Airplanes |
Unsafe Condition
Reduced structural integrity of the fuselage due to potential cracks in the webs of main Frame 25 and Frame 27 between Stringer 6 and Stringer 7.
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Required Actions
Perform a high frequency eddy current (HFEC) inspection of the webs of main Frame 25 and Frame 27 within 250 hours time-in-service after the effective date. If cracks are found, stop drill holes at the ends of cracks under 50.8 mm and perform a detailed visual inspection within 250 hours post-repair. For cracks over 50.8 mm, repair per approved method. Modification 15 S 535 R 00 38 must be done within 425 hours post-repair. Alternative compliance may be approved.
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Compliance Time
Within 250 hours time-in-service after the effective date of this AD
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Affected Aircraft
All ATR42-300 and ATR42-320 series airplanes post Modification 1572, as listed in Aerospatiale Service Bulletin ATR42-53-0057, Revision 2.
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Federal Register Abstract
Fuselage Crack Inspection
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-09-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-09-04 Document Type: AD Final Rules Docket Number: 90-NM-255-AD Subject Heading: AEROSPATIALE Models ATR42-300 and ATR42-320 Series Airplanes Subject: Fuselage Crack Inspection Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/28/1991 Make: ATR - GIE Avions de Transport R gional Model: ATR42-300 | ATR42-320 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 91-09-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-255-AD AMENDMENT: 39-6971 AD NUMBER: 91-09-04 SUBJECT HEADING: AEROSPATIALE Models ATR42-300 and ATR42-320 Series Airplanes ACTION: SUMMARY: DATES: Effective May 28, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-09-04 AEROSPATIALE: Amendment 39-6971. Docket No. 90-NM-255-AD. Applicability: All ATR42-300 and ATR42-320 series airplanes, post Modification 1572, as listed in Aerospatiale Service Bulletin ATR42-53-0057, Revision 2, dated November 9, 1990, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent reduced structural integrity of the fuselage, accomplish the following: A. Within 250 hours time-in-service after the effective date of this AD, perform a high frequency eddy current (HFEC) inspection of the webs of main Frame 25 and Frame 27 (right and left sides) between Stringer 6 and Stringer 7, in accordance with Aerospatiale Service Bulletin ATR42-53-0057, Revision 2, dated November 9, 1990. B. If no crack is found, the airplane may be returned to service. C. If the crack length is less than 50.8 mm (2 inches), prior to further flight, stop drill holes at the ends of the crack, in accordance with Aerospatiale Service Bulletin ATR42-53-0057, Revision 2, dated November 9, 1990; and 1. Perform a detailed visual inspection of the crack ends within 250 hours time-in-service following repair. If the crack length is more than 50.8 mm (2 inches), proceed to paragraph D. of this AD. 2. Within 425 hours time-in-service following repair, accomplish Modification 15 S 535 R 00 38, in accordance with the service bulletin. D. If the crack length is more than 50.8 mm (2 inches), prior to further flight, repair in a manner approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. E. 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. F. 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. All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 03, France. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington. This amendment (39-6971, AD 91-09-04) becomes effective on May 28, 1991. FOOTER:
Document Text
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AD Final Rules - DRS_91-09-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-09-04 Document Type: AD Final Rules Docket Number: 90-NM-255-AD Subject Heading: AEROSPATIALE Models ATR42-300 and ATR42-320 Series Airplanes Subject: Fuselage Crack Inspection Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/28/1991 Make: ATR - GIE Avions de Transport R gional Model: ATR42-300 | ATR42-320 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: 91-09-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-255-AD AMENDMENT: 39-6971 AD NUMBER: 91-09-04 SUBJECT HEADING: AEROSPATIALE Models ATR42-300 and ATR42-320 Series Airplanes ACTION: SUMMARY: DATES: Effective May 28, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-09-04 AEROSPATIALE: Amendment 39-6971. Docket No. 90-NM-255-AD. Applicability: All ATR42-300 and ATR42-320 series airplanes, post Modification 1572, as listed in Aerospatiale Service Bulletin ATR42-53-0057, Revision 2, dated November 9, 1990, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent reduced structural integrity of the fuselage, accomplish the following: A. Within 250 hours time-in-service after the effective date of this AD, perform a high frequency eddy current (HFEC) inspection of the webs of main Frame 25 and Frame 27 (right and left sides) between Stringer 6 and Stringer 7, in accordance with Aerospatiale Service Bulletin ATR42-53-0057, Revision 2, dated November 9, 1990. B. If no crack is found, the airplane may be returned to service. C. If the crack length is less than 50.8 mm (2 inches), prior to further flight, stop drill holes at the ends of the crack, in accordance with Aerospatiale Service Bulletin ATR42-53-0057, Revision 2, dated November 9, 1990; and 1. Perform a detailed visual inspection of the crack ends within 250 hours time-in-service following repair. If the crack length is more than 50.8 mm (2 inches), proceed to paragraph D. of this AD. 2. Within 425 hours time-in-service following repair, accomplish Modification 15 S 535 R 00 38, in accordance with the service bulletin. D. If the crack length is more than 50.8 mm (2 inches), prior to further flight, repair in a manner approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. E. 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. F. 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. All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 03, France. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington. This amendment (39-6971, AD 91-09-04) becomes effective on May 28, 1991. FOOTER:
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