AD 90-24-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 737-200 Series | Airworthiness Directives; BOEING Model 737-200, 737-300 and 737-400 Series Airplanes |
| aircraft | The Boeing Company | 737-300 Series | Airworthiness Directives; BOEING Model 737-200, 737-300 and 737-400 Series Airplanes |
| aircraft | The Boeing Company | 737-400 Series | Airworthiness Directives; BOEING Model 737-200, 737-300 and 737-400 Series Airplanes |
Unsafe Condition
Fastener fracture in the fitting attachment which could result in a loss of the outboard flap.
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Required Actions
Perform a visual inspection of the outboard flap support fitting attach bolts in accordance with specified service bulletins. If bolts are BACB30LE6 or BACB30US6, no further action is required. If BACB30MT bolts are found, perform torque inspections every 1,000 flight hours and replace bolts if they turn below specified torque. Replace any other bolts with BACB30LE or BACB30US prior to further flight.
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Compliance Time
Prior to the accumulation of 5,000 flight hours or within 12 months after the effective date of this AD, whichever occurs later.
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Affected Aircraft
Boeing Model 737-200, 737-300, and 737-400 series airplanes listed in Boeing Alert Service Bulletins 737-57A1206 (dated April 12, 1990) and 737-57A1208 (dated March 29, 1990).
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Outboard Flap Inspection
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_90-24-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 90-24-04 Document Type: AD Final Rules Docket Number: 90-NM-95-AD Subject Heading: Airworthiness Directives; BOEING Model 737-200, 737-300 and 737-400 Series Airplanes Subject: Outboard Flap Inspection Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/24/1990 Make: The Boeing Company Model: 737-200 Series | 737-300 Series | 737-400 Series Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185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: 90-24-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-95-AD AMENDMENT: 39-6809 AD NUMBER: 90-24-04 SUBJECT HEADING: Airworthiness Directives; BOEING Model 737-200, 737-300 and 737-400 Series Airplanes ACTION: SUMMARY: DATES: Effective December 24, 1990. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 90-24-04 BOEING: Amendment 39-6809. Docket No. 90-NM-95-AD. Applicability: Model 737-200 series airplanes, listed in Boeing Alert Service Bulletin 737-57A1206, dated April 12, 1990; and Model 737-300 and 737-400 series airplanes, listed in Boeing Alert Service Bulletin 737-57A1208, dated March 29, 1990; certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent fastener fracture in the fitting attachment which could result in a loss of the outboard flap, accomplish the following: A. Prior to the accumulation of 5,000 flight hours or within 12 months after the effective date of this AD, whichever occurs later, perform a visual inspection of the outboard flap support fitting attach bolts in accordance with Boeing Alert Service Bulletin 737-57A1206, dated April 12, 1990, or Boeing Alert Service Bulletin 737-57A1208, dated March 29, 1990, as applicable. 1. If the bolts are confirmed as BACB30LE6 or BACB30US6, no further action is required at that location. NOTE: A bolt head marking of BACB30LE6, BACB30US6, B30LE6, or B30US6 confirms the correct bolt installation. Oversize bolts BACB30LE7 or BACB30US7 may be installed and are acceptable. 2. If a bolt BACB30MT is found, prior to further flight, and thereafter at intervals not to exceed 1,000 flight hours, perform torque inspections in accordance with Boeing Alert Service Bulletin 737-57A1208, dated March 29, 1990, or Boeing Alert Service Bulletin 737-57A1206, dated April 12, 1990, as applicable. If the bolt turns at or below the specified torque range, prior to further flight, replace it with BACB30LE or BACB30US in accordance with the previously mentioned service bulletins. Replacement of any bolt with bolt BACB30LE or BACB30US constitutes terminating action for the repetitive torque inspections for that bolt. 3. If a bolt other than the one listed in paragraph A.1. or A.2. of this AD is found, prior to further flight, replace the bolt with bolt BACB30LE or BAC30US in accordance with Boeing Alert Service Bulletin 737-57A1208, dated March 29, 1990, or Boeing Alert Service Bulletin 737-57A1206, dated April 12, 1990, as applicable. B. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Transport Airplane Directorate. NOTE: The request should be submitted directly to the Manager, Seattle Aircraft Certification Office (ACO), and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the ACO. 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. All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington. This amendment (39-6809, AD 90-24-04) becomes effective on December 24, 1990. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_90-24-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 90-24-04 Document Type: AD Final Rules Docket Number: 90-NM-95-AD Subject Heading: Airworthiness Directives; BOEING Model 737-200, 737-300 and 737-400 Series Airplanes Subject: Outboard Flap Inspection Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/24/1990 Make: The Boeing Company Model: 737-200 Series | 737-300 Series | 737-400 Series 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: 90-24-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-95-AD AMENDMENT: 39-6809 AD NUMBER: 90-24-04 SUBJECT HEADING: Airworthiness Directives; BOEING Model 737-200, 737-300 and 737-400 Series Airplanes ACTION: SUMMARY: DATES: Effective December 24, 1990. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 90-24-04 BOEING: Amendment 39-6809. Docket No. 90-NM-95-AD. Applicability: Model 737-200 series airplanes, listed in Boeing Alert Service Bulletin 737-57A1206, dated April 12, 1990; and Model 737-300 and 737-400 series airplanes, listed in Boeing Alert Service Bulletin 737-57A1208, dated March 29, 1990; certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent fastener fracture in the fitting attachment which could result in a loss of the outboard flap, accomplish the following: A. Prior to the accumulation of 5,000 flight hours or within 12 months after the effective date of this AD, whichever occurs later, perform a visual inspection of the outboard flap support fitting attach bolts in accordance with Boeing Alert Service Bulletin 737-57A1206, dated April 12, 1990, or Boeing Alert Service Bulletin 737-57A1208, dated March 29, 1990, as applicable. 1. If the bolts are confirmed as BACB30LE6 or BACB30US6, no further action is required at that location. NOTE: A bolt head marking of BACB30LE6, BACB30US6, B30LE6, or B30US6 confirms the correct bolt installation. Oversize bolts BACB30LE7 or BACB30US7 may be installed and are acceptable. 2. If a bolt BACB30MT is found, prior to further flight, and thereafter at intervals not to exceed 1,000 flight hours, perform torque inspections in accordance with Boeing Alert Service Bulletin 737-57A1208, dated March 29, 1990, or Boeing Alert Service Bulletin 737-57A1206, dated April 12, 1990, as applicable. If the bolt turns at or below the specified torque range, prior to further flight, replace it with BACB30LE or BACB30US in accordance with the previously mentioned service bulletins. Replacement of any bolt with bolt BACB30LE or BACB30US constitutes terminating action for the repetitive torque inspections for that bolt. 3. If a bolt other than the one listed in paragraph A.1. or A.2. of this AD is found, prior to further flight, replace the bolt with bolt BACB30LE or BAC30US in accordance with Boeing Alert Service Bulletin 737-57A1208, dated March 29, 1990, or Boeing Alert Service Bulletin 737-57A1206, dated April 12, 1990, as applicable. B. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Transport Airplane Directorate. NOTE: The request should be submitted directly to the Manager, Seattle Aircraft Certification Office (ACO), and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the ACO. 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. All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington. This amendment (39-6809, AD 90-24-04) becomes effective on December 24, 1990. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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