AD 77-09-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Dowty Propellers | (c) R175/4-30-4/ | DOWTY ROTOL Models (c)R175/4-30-4/13E and (c)R212/4-30-4/22 Propellers |
| aircraft | Dowty Propellers | (c) R212/4-30-4/ | DOWTY ROTOL Models (c)R175/4-30-4/13E and (c)R212/4-30-4/22 Propellers |
| propeller | Dowty Propellers | (c) R175/4-30-4/ | DOWTY ROTOL Models (c)R175/4-30-4/13E and (c)R212/4-30-4/22 Propellers |
| propeller | Dowty Propellers | (c) R212/4-30-4/ | DOWTY ROTOL Models (c)R175/4-30-4/13E and (c)R212/4-30-4/22 Propellers |
Unsafe Condition
Cracking and possible failure of the hub driving center due to improper machining.
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Required Actions
Inspect the hub driving center to verify correct machining per Dowty Rotol Service Bulletin 61-857. If incorrectly machined, rework to salvage scheme No. 640144020. Equivalent methods require approval by the Chief, Aircraft Certification Staff, FAA.
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Compliance Time
At the next propeller overhaul or within the next 4700 hours propeller time in service after the effective date of this AD, whichever occurs first.
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Affected Aircraft
Dowty Propellers models (c)R175/4-30-4/13E and (c)R212/4-30-4/22 propellers with hub and driving center P/N 601023166, 601023223, or 601023227 modified to Mod. No. (c)VP2381 standard.
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Federal Register Abstract
Hub Driving Center
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_77-09-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 77-09-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: DOWTY ROTOL Models (c)R175/4-30-4/13E and (c)R212/4-30-4/22 Propellers Subject: Hub Driving Center Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/19/1977 Make: Dowty Propellers Model: (c) R175/4-30-4/ | (c) R212/4-30-4/ Product Type: Propeller Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 77-09-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2890 AD NUMBER: 77-09-07 SUBJECT HEADING: DOWTY ROTOL Models (c)R175/4-30-4/13E and (c)R212/4-30-4/22 Propellers ACTION: SUMMARY: DATES: Effective May 19, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 77-09-07 DOWTY ROTOL: Amendment 39-2890. Applies to Dowty Rotol Type (c)R175/4-30-4/13E and (c)R212/4-30-4/22 propellers having hub and driving center, P/N 601023166, 601023223, or 601023227 modified to Dowty Rotol Mod. No. (c)VP2381 standard. These propellers are installed on, but not necessarily limited to, Fokker Model F-27 Mks. 100, 300, and 700 Series and Hawker Siddeley Model 748 Series 2A airplanes. Compliance is required at the next propeller overhaul or within the next 4700 hours propeller time in service after the effective date of this AD, whichever occurs first, unless already accomplished. To prevent cracking and possible failure of the hub driving center due to improper machining, accomplish the following: (a) For Type (c)R175/4-30-4/13E propellers, that incorporate the following hub and driving center assemblies, rework the hub driving center to salvage scheme No. 640144020 in accordance with Paragraph 2A of Dowty Rotol Service Bulletin 61-857, dated February 3, 1975, or an equivalent approved in accordance with Paragraph (c) of this AD: Hub and Driving Center Assembly Serial Numbers 175/58/67 175/58/72 175/58/91 175/58/146 175/59/184 (b) For Type (c)R175/4-30-4/13E propellers that incorporate hub and driving center assemblies having serial numbers not listed in paragraph (a) of this AD and Type (c)R212/4-30- 4/22 propellers - (1) Inspect the hub driving center to verify correct machining in accordance with Paragraph 2B of Dowty Rotol Service Bulletin 61-857 dated February 3, 1975, or an equivalent approved in accordance with paragraph (c) of this AD; and (2) If the hub driving center is found to have been incorrectly machined, rework it to salvage scheme No. 640144020 in accordance with Paragraph 2A of Dowty Rotol Service Bulletin 61-857, dated February 3, 1975, or an equivalent approved in accordance with paragraph (c) of this AD. (c) The equivalent means of compliance specified in paragraphs (a) and (b) of this AD must be approved by the Chief, Aircraft Certification Staff, FAA, Europe, Africa and Middle East Region c/o American Embassy, APO New York, N.Y. 09667. This amendment becomes effective May 19, 1977. FOOTER:
Document Text
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AD Final Rules - DRS_77-09-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 77-09-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: DOWTY ROTOL Models (c)R175/4-30-4/13E and (c)R212/4-30-4/22 Propellers Subject: Hub Driving Center Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/19/1977 Make: Dowty Propellers Model: (c) R175/4-30-4/ | (c) R212/4-30-4/ 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: 77-09-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2890 AD NUMBER: 77-09-07 SUBJECT HEADING: DOWTY ROTOL Models (c)R175/4-30-4/13E and (c)R212/4-30-4/22 Propellers ACTION: SUMMARY: DATES: Effective May 19, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 77-09-07 DOWTY ROTOL: Amendment 39-2890. Applies to Dowty Rotol Type (c)R175/4-30-4/13E and (c)R212/4-30-4/22 propellers having hub and driving center, P/N 601023166, 601023223, or 601023227 modified to Dowty Rotol Mod. No. (c)VP2381 standard. These propellers are installed on, but not necessarily limited to, Fokker Model F-27 Mks. 100, 300, and 700 Series and Hawker Siddeley Model 748 Series 2A airplanes. Compliance is required at the next propeller overhaul or within the next 4700 hours propeller time in service after the effective date of this AD, whichever occurs first, unless already accomplished. To prevent cracking and possible failure of the hub driving center due to improper machining, accomplish the following: (a) For Type (c)R175/4-30-4/13E propellers, that incorporate the following hub and driving center assemblies, rework the hub driving center to salvage scheme No. 640144020 in accordance with Paragraph 2A of Dowty Rotol Service Bulletin 61-857, dated February 3, 1975, or an equivalent approved in accordance with Paragraph (c) of this AD: Hub and Driving Center Assembly Serial Numbers 175/58/67 175/58/72 175/58/91 175/58/146 175/59/184 (b) For Type (c)R175/4-30-4/13E propellers that incorporate hub and driving center assemblies having serial numbers not listed in paragraph (a) of this AD and Type (c)R212/4-30- 4/22 propellers - (1) Inspect the hub driving center to verify correct machining in accordance with Paragraph 2B of Dowty Rotol Service Bulletin 61-857 dated February 3, 1975, or an equivalent approved in accordance with paragraph (c) of this AD; and (2) If the hub driving center is found to have been incorrectly machined, rework it to salvage scheme No. 640144020 in accordance with Paragraph 2A of Dowty Rotol Service Bulletin 61-857, dated February 3, 1975, or an equivalent approved in accordance with paragraph (c) of this AD. (c) The equivalent means of compliance specified in paragraphs (a) and (b) of this AD must be approved by the Chief, Aircraft Certification Staff, FAA, Europe, Africa and Middle East Region c/o American Embassy, APO New York, N.Y. 09667. This amendment becomes effective May 19, 1977. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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Related Airworthiness Directives
2010-10-23
final ruleAirworthiness Directives; Dowty Propellers R175/4-30-4/13; R175/4-30-4/13e; R184/4-30-4/50; R193/4-30-4/50; R193/4-30-4/61; R193/4-30-4/64; R193/4-30-4/65; R193/4-30-4/66; R.209/4-40-4.5/2; R212/4-30-4/22; R.245/4-40-4.5/13; R257/4-30-4/60; and R.259/4-40-4.5/17 Model Propellers
Unsafe Condition: could result in reduced controllability of the airplane.
81-16-03
final ruleDOWTY ROTOL LTD. Models R175/4-30-4/13E Propellers
Unsafe Condition: Propeller failure due to cracking of the propeller hub front wall to snout radius.
72-14-01
final ruleDOWTY ROTOL, LTD Models (c)R130/4-20-4/12E, (c)R186/4-30-4/16, (c)R187/4-30-4/18, (c)R193/4-30-4/50, (c)R184/4-30-4/50, (c)R259/4-40-4.5/17, (c)R148/4-20-4/21E, (c)R175/4-30-4/13E, (c)R179/4- 20-4/33, (c)R257/4-30-4/60, (c)R245/4-40-4.5/13, and (c)R209/4-40-4.5/2 Propellers
Unsafe Condition: Failure of a propeller blade due to the disengagement of the blade bearing retaining bolts resulting from excessive wear on the teeth of the locking segments.
72-07-07
final ruleDOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30
Unsafe Condition: Fatigue failure of propeller blades or blade bearings due to loss of bearing pre-load from discrepancies in ground tracks or improper assembly.