AD 68-20-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Dowty Propellers | (c) R184/4-30-4/ | DOWTY ROTOL Models (c) R.193/4-30-4/50, (c) R.257/4-30-4/60, and (c) R.184/4-30-4/50 Propellers |
| aircraft | Dowty Propellers | (c) R193/4-30-4/ | DOWTY ROTOL Models (c) R.193/4-30-4/50, (c) R.257/4-30-4/60, and (c) R.184/4-30-4/50 Propellers |
| aircraft | Dowty Propellers | (c) R257/4-30-4/ | DOWTY ROTOL Models (c) R.193/4-30-4/50, (c) R.257/4-30-4/60, and (c) R.184/4-30-4/50 Propellers |
| propeller | Dowty Propellers | (c) R184/4-30-4/ | DOWTY ROTOL Models (c) R.193/4-30-4/50, (c) R.257/4-30-4/60, and (c) R.184/4-30-4/50 Propellers |
| propeller | Dowty Propellers | (c) R193/4-30-4/ | DOWTY ROTOL Models (c) R.193/4-30-4/50, (c) R.257/4-30-4/60, and (c) R.184/4-30-4/50 Propellers |
| propeller | Dowty Propellers | (c) R257/4-30-4/ | DOWTY ROTOL Models (c) R.193/4-30-4/50, (c) R.257/4-30-4/60, and (c) R.184/4-30-4/50 Propellers |
Unsafe Condition
Failure of the propeller hub driving center, part number RA 57500, due to cracks.
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Required Actions
Incorporate Dowty Rotol Modification (c) VP.2486 per Service Bulletin 61.573B or equivalent. Inspect hubs with magnifying glass and magnetic particle fluid method per SB 61-633. Replace cracked driving centers before flight. For R.184/4-30-4/50 propellers, inspections and modifications depend on hours time in service as specified.
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Compliance Time
Within the next 4500 hours time in service after the effective date for most propellers, or as specified for R.184/4-30-4/50 based on their time in service on the effective date.
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Affected Aircraft
Dowty Rotol propellers models (c) R.193/4-30-4/50, (c) R.257/4-30-4/60, and (c) R.184/4-30-4/50 installed on specific aircraft models as listed.
AI-generated summary from the source AD text. Verify against the official source before acting.
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_68-20-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 68-20-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: DOWTY ROTOL Models (c) R.193/4-30-4/50, (c) R.257/4-30-4/60, and (c) R.184/4-30-4/50 Propellers Subject: Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/08/1968 Make: Dowty Propellers Model: (c) R184/4-30-4/ | (c) R193/4-30-4/ | (c) R257/4-30-4/ Product Type: Propeller Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 68-20-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-664 AD NUMBER: 68-20-07 SUBJECT HEADING: DOWTY ROTOL Models (c) R.193/4-30-4/50, (c) R.257/4-30-4/60, and (c) R.184/4-30-4/50 Propellers ACTION: SUMMARY: DATES: Effective October 8, 1968. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 68-20-07 DOWTY ROTOL: Amendment 39-664. Applies to Dowty Rotol Propellers (c) R.193/4-30-4/50 installed on Fairchild F. 27A-F-G-J, FH.227 and Fokker F.27 Mk 400, (c) R.257/4-30-4/60 installed on Fairchild FH.227B, FH.227C, FH.227D and FH.227E, and (c) R.184/4-30-4/50 installed on Grumman G-159. Compliance required as indicated unless already accomplished. To prevent failure of the propeller hub driving center, P/N RA 57500, accomplish the following: (a) For all propellers except the (c) R.184/4-30-4/50 propeller, incorporate Dowty Rotol Modification (c) VP.2486, in accordance with Dowty Rotol Service Bulletin No. 61.573B dated June, 1968, or later ARB approved issue, or FAA approved equivalent at the next scheduled overhaul or within the next 4500 hours time in service after the effective date of this AD, whichever occurs first. (b) For (c) R.184/4-30-4/50 propellers accomplish the following: (1) For propeller hubs having 2500 or more hours time in service on the effective date of this AD and that have not been modified in accordance with paragraph (5), inspect the hub in accordance with paragraph (3) within the next 50 hours time in service and incorporate the modification specified in paragraph (5) at the next scheduled overhaul or prior to the accumulation of 400 hours time in service after the effective date of this AD, whichever occurs first. (2) For propeller hubs having less than 2500 hours time in service on the effective date of this AD and that have not been modified in accordance with paragraph (5), inspect the hub in accordance with paragraph (3) prior to the accumulation of 2550 hours time in service and incorporate the modification specified in paragraph (5) within the next 400 hours time in service or prior to the accumulation of 2500 hours time in service, whichever occurs later. (3) Inspect the rear face of the hub driving center flange with a magnifying glass and by the magnetic particle fluid method in accordance with Dowty Rotol Service Bulletin 61-633 dated June 1968, or later approved ARB issue, or an FAA approved equivalent. (4) If cracked hub driving centers are detected during any inspection, before further flight replace the propeller hub driving center with a serviceable part of the same part number having no cracks. (5) Incorporate Dowty Rotol Modification No. (c) VP.2486 in accordance with Dowty Rotol Service Bulletin No. 61-573A dated June 1968, or later ARB approved issue, or an FAA approved equivalent. The inspection specified in paragraph (3) is not required in hubs modified in accordance with this paragraph. This supersedes Amendment 39-587 (33 F.R. 5866), AD 68-08-05. This amendment becomes effective October 8, 1968. FOOTER:
Document Text
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AD Final Rules - DRS_68-20-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 68-20-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: DOWTY ROTOL Models (c) R.193/4-30-4/50, (c) R.257/4-30-4/60, and (c) R.184/4-30-4/50 Propellers Subject: Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/08/1968 Make: Dowty Propellers Model: (c) R184/4-30-4/ | (c) R193/4-30-4/ | (c) R257/4-30-4/ Product Type: Propeller Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 68-20-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-664 AD NUMBER: 68-20-07 SUBJECT HEADING: DOWTY ROTOL Models (c) R.193/4-30-4/50, (c) R.257/4-30-4/60, and (c) R.184/4-30-4/50 Propellers ACTION: SUMMARY: DATES: Effective October 8, 1968. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 68-20-07 DOWTY ROTOL: Amendment 39-664. Applies to Dowty Rotol Propellers (c) R.193/4-30-4/50 installed on Fairchild F. 27A-F-G-J, FH.227 and Fokker F.27 Mk 400, (c) R.257/4-30-4/60 installed on Fairchild FH.227B, FH.227C, FH.227D and FH.227E, and (c) R.184/4-30-4/50 installed on Grumman G-159. Compliance required as indicated unless already accomplished. To prevent failure of the propeller hub driving center, P/N RA 57500, accomplish the following: (a) For all propellers except the (c) R.184/4-30-4/50 propeller, incorporate Dowty Rotol Modification (c) VP.2486, in accordance with Dowty Rotol Service Bulletin No. 61.573B dated June, 1968, or later ARB approved issue, or FAA approved equivalent at the next scheduled overhaul or within the next 4500 hours time in service after the effective date of this AD, whichever occurs first. (b) For (c) R.184/4-30-4/50 propellers accomplish the following: (1) For propeller hubs having 2500 or more hours time in service on the effective date of this AD and that have not been modified in accordance with paragraph (5), inspect the hub in accordance with paragraph (3) within the next 50 hours time in service and incorporate the modification specified in paragraph (5) at the next scheduled overhaul or prior to the accumulation of 400 hours time in service after the effective date of this AD, whichever occurs first. (2) For propeller hubs having less than 2500 hours time in service on the effective date of this AD and that have not been modified in accordance with paragraph (5), inspect the hub in accordance with paragraph (3) prior to the accumulation of 2550 hours time in service and incorporate the modification specified in paragraph (5) within the next 400 hours time in service or prior to the accumulation of 2500 hours time in service, whichever occurs later. (3) Inspect the rear face of the hub driving center flange with a magnifying glass and by the magnetic particle fluid method in accordance with Dowty Rotol Service Bulletin 61-633 dated June 1968, or later approved ARB issue, or an FAA approved equivalent. (4) If cracked hub driving centers are detected during any inspection, before further flight replace the propeller hub driving center with a serviceable part of the same part number having no cracks. (5) Incorporate Dowty Rotol Modification No. (c) VP.2486 in accordance with Dowty Rotol Service Bulletin No. 61-573A dated June 1968, or later ARB approved issue, or an FAA approved equivalent. The inspection specified in paragraph (3) is not required in hubs modified in accordance with this paragraph. This supersedes Amendment 39-587 (33 F.R. 5866), AD 68-08-05. This amendment becomes effective October 8, 1968. FOOTER:
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