AD 87-18-11
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | MD Helicopters, Inc. | 369D | Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (Hughes Helicopters, Inc.) Model 369D, E, F, and FF Helicopters |
| aircraft | MD Helicopters, Inc. | 369E | Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (Hughes Helicopters, Inc.) Model 369D, E, F, and FF Helicopters |
| aircraft | MD Helicopters, Inc. | 369F | Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (Hughes Helicopters, Inc.) Model 369D, E, F, and FF Helicopters |
| aircraft | MD Helicopters, Inc. | 369FF | Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (Hughes Helicopters, Inc.) Model 369D, E, F, and FF Helicopters |
Unsafe Condition
Possible loss of tail rotor control due to potential cracking in the main transmission tail rotor output drive pinion shaft (P/N 369D25125-BSC or -11).
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Required Actions
Perform a one-time magnetic particle and visual inspection on the pinion shaft within specified timeframes. Remove shafts with non-compliant fillet radius, cracks, or defects from service before further flight. Rework discrepant shafts without cracks as per MDHC procedures.
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Compliance Time
Within the next 25 hours' time-in-service after September 1, 1987, for transmissions with specified serial numbers; within 100 hours' time-in-service for others.
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Affected Aircraft
MD Helicopters, Inc. Models 369D, E, F, FF with main transmission (P/N 369D25100-BSC or -501) and tail rotor output drive pinion shaft (P/N 369D25125-BSC or -11). Transmission serial numbers include 1989, 1992, 1993, 1998-2000, 2002-2082, 2084, 2085. Pinion shaft serial numbers 1474-1502, 1504-1547, 1549-1561, 1563-1564, 1566 are subject to immediate removal.
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Federal Register Abstract
Main Rotor Transmission And Drive Shaft
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_87-18-11.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 87-18-11 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (Hughes Helicopters, Inc.) Mod...Show more Subject: Main Rotor Transmission And Drive Shaft Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/01/1987 Make: MD Helicopters, Inc. Model: 369D | 369E | 369F | 369FF Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 87-18-11 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5678 AD NUMBER: 87-18-11 SUBJECT HEADING: Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (Hughes Helicopters, Inc.) Model 369D, E, F, and FF Helicopters ACTION: SUMMARY: DATES: Effective September 1, 1987. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 87-18-11 MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (Hughes Helicopters, Inc.): Amendment 39-5678. Applies to all Model 369D, E, F, and FF helicopters, certificated in any category, equipped with MDHC main transmission (P/N 369D25100-BSC or- 501) which has tail rotor output drive pinion shaft (P/N 369D25125-BSC or -11) installed. Compliance is required as indicated, unless previously accomplished. To prevent possible loss of tail rotor control, accomplish the following: (a) Within the next 25 hours' time-in-service after the effective date of this AD, perform a one-time magnetic particle and visual inspection on the main transmission tail rotor output drive pinion shaft (P/N 369D25125-BSC or -11) on helicopters with the following serialized main rotor transmission in accordance with procedures detailed in paragraphs (c) through (f) of this AD. TRANSMISSION SERIAL NUMBER 1989 1992 and 1993 1998 through 2000 2002 through 2082 2084 and 2085 If the tail rotor output drive pinion shaft serial number is contained in the list below, remove the shaft from service prior to further flight. TAIL ROTOR OUTPUT DRIVE PINION SHAFT SERIAL NUMBERS 1474 through 1502 1504 through 1547 1549 through 1561 1563 and 1564 1566 (b) Within the next 100 hours' time-in-service after the effective date of this AD, perform a one-time magnetic particle and visual inspection on the main transmission tail rotor output drive pinion shaft (P/N 369D25125-BSC or -11) on all affected helicopters with transmission serial numbers other than those listed above in accordance with procedures detailed in paragraphs (c) through (f) of this AD. (c) Verify that the tail rotor output drive pinion shaft has an undercut style fillet radius as shown in Figure 1 of MDHC Mandatory SIN DN-147/EN-35/FN-24, dated April 23, 1987, or FAA-approved equivalent. Remove parts which do not have the undercut from service prior to further flight. NOTE: Tail rotor output drive pinion shafts removed from service in accordance with paragraph (c) may be returned to MDHC for rework if a magnetic particle inspection of the part does not show any crack indications. (d) Perform a magnetic particle inspection of the tail rotor output drive pinion shaft. Remove parts which show indications of cracking found during magnetic particle inspection from service prior to further flight. (e) Inspect the tail rotor output drive pinion shafts for scratches, tooling marks, corrosion, or other minor surface defects in the fillet radius or elsewhere on the shaft in accordance with paragraphs c. (4), c. (5), and c. (6) of MDHC Mandatory SIN DN-147/EN- 35/FN-24, dated April 23, 1987. Prior to further flight, rework discrepant shafts that show no indication of cracks in accordance with procedures stated in paragraph d. of MDHC Mandatory SIN DN-147/EN-35/FN-24, dated April 23, 1987. (f) Special flight permits may be issued in accordance with FAR Sections 21.197 and 21.199 to ferry aircraft to a maintenance base in order to comply with the requirements of this AD. The procedure shall be done in accordance with MDHC SIN DN-147/EN-35/FN-24, dated April 23, 1987. This incorporation by reference was approved by the Director of-the Federal Register in accordance with 5 U.S.C. 552 (a) (1). Copies may be obtained from MDHC, 500 E. McDowell Road, Mesa, Arizona. Copies may be inspected at the Office of the Regional Counsel, FAA, Southwest Region, 4400 Blue Mound Road, Fort Worth, Texas, or at the Office of the Federal Register, 1100 L. Street, NW., Room 8401, Washington, D.C. This amendment becomes effective September 1, 1987. FOOTER:
Document Text
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AD Final Rules - DRS_87-18-11.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 87-18-11 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (Hughes Helicopters, Inc.) Mod...Show more Subject: Main Rotor Transmission And Drive Shaft Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/01/1987 Make: MD Helicopters, Inc. Model: 369D | 369E | 369F | 369FF Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 87-18-11 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5678 AD NUMBER: 87-18-11 SUBJECT HEADING: Airworthiness Directives; MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (Hughes Helicopters, Inc.) Model 369D, E, F, and FF Helicopters ACTION: SUMMARY: DATES: Effective September 1, 1987. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 87-18-11 MCDONNELL DOUGLAS HELICOPTER COMPANY (MDHC) (Hughes Helicopters, Inc.): Amendment 39-5678. Applies to all Model 369D, E, F, and FF helicopters, certificated in any category, equipped with MDHC main transmission (P/N 369D25100-BSC or- 501) which has tail rotor output drive pinion shaft (P/N 369D25125-BSC or -11) installed. Compliance is required as indicated, unless previously accomplished. To prevent possible loss of tail rotor control, accomplish the following: (a) Within the next 25 hours' time-in-service after the effective date of this AD, perform a one-time magnetic particle and visual inspection on the main transmission tail rotor output drive pinion shaft (P/N 369D25125-BSC or -11) on helicopters with the following serialized main rotor transmission in accordance with procedures detailed in paragraphs (c) through (f) of this AD. TRANSMISSION SERIAL NUMBER 1989 1992 and 1993 1998 through 2000 2002 through 2082 2084 and 2085 If the tail rotor output drive pinion shaft serial number is contained in the list below, remove the shaft from service prior to further flight. TAIL ROTOR OUTPUT DRIVE PINION SHAFT SERIAL NUMBERS 1474 through 1502 1504 through 1547 1549 through 1561 1563 and 1564 1566 (b) Within the next 100 hours' time-in-service after the effective date of this AD, perform a one-time magnetic particle and visual inspection on the main transmission tail rotor output drive pinion shaft (P/N 369D25125-BSC or -11) on all affected helicopters with transmission serial numbers other than those listed above in accordance with procedures detailed in paragraphs (c) through (f) of this AD. (c) Verify that the tail rotor output drive pinion shaft has an undercut style fillet radius as shown in Figure 1 of MDHC Mandatory SIN DN-147/EN-35/FN-24, dated April 23, 1987, or FAA-approved equivalent. Remove parts which do not have the undercut from service prior to further flight. NOTE: Tail rotor output drive pinion shafts removed from service in accordance with paragraph (c) may be returned to MDHC for rework if a magnetic particle inspection of the part does not show any crack indications. (d) Perform a magnetic particle inspection of the tail rotor output drive pinion shaft. Remove parts which show indications of cracking found during magnetic particle inspection from service prior to further flight. (e) Inspect the tail rotor output drive pinion shafts for scratches, tooling marks, corrosion, or other minor surface defects in the fillet radius or elsewhere on the shaft in accordance with paragraphs c. (4), c. (5), and c. (6) of MDHC Mandatory SIN DN-147/EN- 35/FN-24, dated April 23, 1987. Prior to further flight, rework discrepant shafts that show no indication of cracks in accordance with procedures stated in paragraph d. of MDHC Mandatory SIN DN-147/EN-35/FN-24, dated April 23, 1987. (f) Special flight permits may be issued in accordance with FAR Sections 21.197 and 21.199 to ferry aircraft to a maintenance base in order to comply with the requirements of this AD. The procedure shall be done in accordance with MDHC SIN DN-147/EN-35/FN-24, dated April 23, 1987. This incorporation by reference was approved by the Director of-the Federal Register in accordance with 5 U.S.C. 552 (a) (1). Copies may be obtained from MDHC, 500 E. McDowell Road, Mesa, Arizona. Copies may be inspected at the Office of the Regional Counsel, FAA, Southwest Region, 4400 Blue Mound Road, Fort Worth, Texas, or at the Office of the Federal Register, 1100 L. Street, NW., Room 8401, Washington, D.C. This amendment becomes effective September 1, 1987. FOOTER:
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