AD 72-07-07
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Dowty Propellers | (c) R.284/3-20-3/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| aircraft | Dowty Propellers | (c) R130/4-20-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| aircraft | Dowty Propellers | (c) R141/4-20-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| aircraft | Dowty Propellers | (c) R147/4-20-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| aircraft | Dowty Propellers | (c) R148/4-20-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| aircraft | Dowty Propellers | (c) R175/4-30-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| aircraft | Dowty Propellers | (c) R179/4-20-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| aircraft | Dowty Propellers | (c) R184/4-30-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| aircraft | Dowty Propellers | (c) R186/4-30-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| aircraft | Dowty Propellers | (c) R187/4-30 | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R.284/3-20-3/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R130/4-20-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R141/4-20-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R147/4-20-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R148/4-20-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R175/4-30-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R179/4-20-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R184/4-30-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R186/4-30-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R187/4-30 | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R193/4-30-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R201/4-30-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R212/4-30-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R251/4-30-4/ | DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 |
| propeller | Dowty Propellers | (c) R257/4-30-4/ | DOWTY 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.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect blade bearings by measuring and recording bearing torque and center race spigot mean diameter before and after removal of pre-load, following Dowty Rotol Service Letter No. SER/SSL/1. Determine serviceability based on expansion values and either return to service, remove from service, or send for load-expansion torque test.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 400 hours' time in service after the effective date (March 29, 1972) or at the next disassembly of a bearing from a blade for cause, whichever occurs sooner. Thereafter, at intervals not exceeding 5,000 hours' time in service or at each disassembly for cause.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Dowty Propellers models R.284/3-20-3/, R130/4-20-4/, R141/4-20-4/, R147/4-20-4/, R148/4-20-4/, and others with blade root sizes Nos. 20 and 30, installed on Fairchild F-27, Fairchild Hiller F-227, Armstrong Whitworth AW 650, Vickers Viscount 745/810, and Grumman G-159 series airplanes.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Blade Bearing
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_72-07-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 72-07-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 Subject: Blade Bearing Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/29/1972 Make: Dowty Propellers Model: (c) R.284/3-20-3/ | (c) R130/4-20-4/ | (c) R141/4-20-4/ | (c) R147/4-20-4/ | (c) R148/4-20-4/ | (c) ...Show more 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: 72-07-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1417 AD NUMBER: 72-07-07 SUBJECT HEADING: DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 ACTION: SUMMARY: DATES: Effective March 29, 1972. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 72-07-07 DOWTY ROTOL: Amdt. 39-1417. Applies to all propellers with blade root sizes Nos. 20 and 30. These propellers are installed on but not limited to Fairchild F-27 Series; Fairchild Hiller F-227 Series; Armstrong Whitworth Argosy Type AW 650 Series; Vickers Viscount 745 and 810 Series; and Grumman G-159 Series airplanes. Compliance is required as indicated unless already accomplished. To prevent possible fatigue failure of propeller blades or blade bearings as a result of loss of bearing pre-load due to discrepancies in the ground tracks or improper assembly of the propeller blade bearing, accomplish the following: (a) For propellers with any bearing identified by one of the Bearing Identification Numbers listed in subparagraph (3) that has not been last reground by an FAA-approved repair facility subsequent to April 21, 1971, or by the bearing manufacturer, comply with paragraph (c)(1) within the next 400 hours' time in service after the effective date of this AD, or at the next disassembly of a bearing from a blade for cause, whichever occurs sooner. Thereafter, comply with paragraph (c)(2) at the following intervals: (1) For propellers for which there is a scheduled blade overhaul, at each disassembly of a bearing from a blade for cause, including disassembly at overhaul. (2) For propellers for which there is no scheduled blade overhaul, at each disassembly of a bearing from a blade for cause, and at intervals not to exceed 5,000 hours' time in service on a blade from the last inspection. (3) Bearing Identification Numbers: BRGS. BRGS. BRGS. BRGS. BRGS. BRGS. 11309 10449/R 16726 16331/R/R 18305/R 4696/R/R 16350 9660/R 15071/R 947/R/R 18328/R 13098 13917/R/R 15337 13345/R 17078/R N16672/R 18077/R N15311 1237/R/R/R 2280/R/R 2847/R/R N8225/R N17430 3670/R/R N13981 N15427 16970/R 11781/R N17368 7801/R/R N14011 16498/R N17313 2629/R N13980 N4629/R 15523/R/R 12825/R N17424 N13977 20448/R 15959/R N17829/R N16327 12794/R N11240/R N15257/R N16078/R N16167/R 5901/R/R 10571 N21240N/R 14731/R N14495/R N16490/R 7060/R/R N9730/R N16898/R 17082/R 5756/R 18119 1298/R N16532 16831/R N18287 3626/R/R 21243 15309/R N18236 18081/R 11766/R 16790 3258/R 16512/R N12714 11838/R/R 9180/R 4416/R 20441/R/R N18094 2489/R 15302/R N10966 N11149 14352/R 3054/R 16339/R N3682/R/R 18055 N15574 N11761 1400/R/R 11751/R/R 16295 N13837 16179/R/R N14938 11346/R/R N13821 14163 7049/R N11778/R/R N13822 4786/R/R/R 14165/R 14734 N13833 1989/R/R 12749/R/R 1851/R/R/R/R N16977/R N20911N 315/R/R 13347/R 9048/R 4709/R N9296 4354/R/R N4689/R 14019/R/R N15489/R 20045N/R N15890 13969 N434/R/R 21280N/R/R 13993/R N20340 N16773 14386/R/R 15567 17018 11764/R 10422/R/R N16706 15220/R 14364/R 10554/R N16647/R 5801/R 2753/R/R 14213/R N15285 11765 N11358/R/R 13559/R/R 16981/R 15275 12038 N21248N/R 12746/R 20449/R/R 15538 11754/R N18103 12571/R/R N15703 N21048N/R 9668 13853/R N15691 20823/R/R 4131/R/R 11756 N16858 5235 5155/R N7479/R N17408 N5007/R/R N11724/R (b) For all other propellers, comply with the following: (1) For propellers for which there is a scheduled blade overhaul - (i) Comply with paragraph (c)(1) at the next disassembly of a bearing from a blade for cause, including disassembly at overhaul; and (ii) Thereafter comply with paragraph (c)(2) at each disassembly of a bearing from a blade for cause, including disassembly at overhaul. (2) For propellers for which there is no scheduled blade overhaul - (i) Comply with paragraph (c)(1) at the next disassembly of a bearing from a blade for cause or before the accumulation of 5,000 hours' time in service on the propeller from the last inspection, whichever occurs sooner; and (ii) Thereafter comply with paragraph (c)(2) at each disassembly of a bearing from a blade for cause and at intervals not to exceed 5,000 hours' time in service on a blade from the last inspection. (c) Inspect blade bearings in accordance with either subparagraph (1) or (2), as applicable. (1) For the initial inspections required by paragraphs (a) and (b) disassemble the propeller to the stage where the assembly of blades complete with bearings are removed from the hub and inspect each blade bearing in accordance with paragraph (d). (2) For the repetitive inspections required by paragraphs (a) and (b), inspect affected blade bearings in accordance with paragraph (d). (d) Measure and record the bearing torque and the center race spigot mean diameter before and after removal of bearing pre-load; and compute the spigot expansion, in accordance with the procedures specified in Dowty Rotol Service Letter No. SER/SSL/1, dated August 12, 1971, or an FAA-approved equivalent. If the spigot expansion, for a bearing size and blade bearing assembly specified in Columns 1 and 2, respectively, of the following table, is - (1) Equal to or greater than Expansion Value A (Column 4), the bearing assembly, blade, and blade bolt may be returned to service. (2) Less than Expansion Value B (Column 5), remove the bearing assembly, blade, and blade bolt from service and mark them in a manner that will prevent their further use. (3) Less than Expansion Value A, but equal to or greater than Expansion Value B (Column 5), before further operation of the blade, blade bolt, and bearing assembly return the bearing assembly to Dowty Rotol, Inc., Arlington, Virginia, or Dowty-Rotol Ltd., Service Department Cheltenham Road, Gloucester, England, for a load-expansion torque test to determine the remaining service life of the blade and blade bolt. The measurements of bearing torque and the mean spigot diameter before and after removal of the blade bearing preload required by this paragraph must accompany the parts. (Col. 1) Bearing Size (Col. 2) Blade Bearing Assembly (Col. 3) Normal Spigot Expansion (Col. 4) Expansion Value A (Col.5) Expansion Value B RA38965 .0055 RA38965Z to .0050 .0035 RA38965Z-1 .0060 No. 20 RA54100 .0050 RA54100Z to .0040 .0030 RA54100Z-1 .0055 RA57099 .0040 RA57099Z to .0035 .0025 RA57099Z-1 .0045 No. 30 RA22355/1 .0035 RA22355/2 to .0030 .0022 .0040 (e) An inspection performed following any period in service since the last installation of the propeller, may be accepted in lieu of the initial inspection required by paragraph (a) to be performed within the next 400 hours' time in service after the effective date of this AD, if the records of that inspection are submitted to an FAA Maintenance Inspector and he determines that the inspection included a computation of spigot expansion performed in accordance with the procedures specified in paragraph (d) which established that the spigot expansion values were equal to or greater than the applicable Expansion Value A (Column 4) specified in paragraph (d) for the bearing size and blade bearing assembly. This amendment becomes effective March 29, 1972. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_72-07-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 72-07-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 Subject: Blade Bearing Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/29/1972 Make: Dowty Propellers Model: (c) R.284/3-20-3/ | (c) R130/4-20-4/ | (c) R141/4-20-4/ | (c) R147/4-20-4/ | (c) R148/4-20-4/ | (c) ...Show more 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: 72-07-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1417 AD NUMBER: 72-07-07 SUBJECT HEADING: DOWTY ROTOL applies to all propellers with blade root sizes Nos. 20 and 30 ACTION: SUMMARY: DATES: Effective March 29, 1972. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 72-07-07 DOWTY ROTOL: Amdt. 39-1417. Applies to all propellers with blade root sizes Nos. 20 and 30. These propellers are installed on but not limited to Fairchild F-27 Series; Fairchild Hiller F-227 Series; Armstrong Whitworth Argosy Type AW 650 Series; Vickers Viscount 745 and 810 Series; and Grumman G-159 Series airplanes. Compliance is required as indicated unless already accomplished. To prevent possible fatigue failure of propeller blades or blade bearings as a result of loss of bearing pre-load due to discrepancies in the ground tracks or improper assembly of the propeller blade bearing, accomplish the following: (a) For propellers with any bearing identified by one of the Bearing Identification Numbers listed in subparagraph (3) that has not been last reground by an FAA-approved repair facility subsequent to April 21, 1971, or by the bearing manufacturer, comply with paragraph (c)(1) within the next 400 hours' time in service after the effective date of this AD, or at the next disassembly of a bearing from a blade for cause, whichever occurs sooner. Thereafter, comply with paragraph (c)(2) at the following intervals: (1) For propellers for which there is a scheduled blade overhaul, at each disassembly of a bearing from a blade for cause, including disassembly at overhaul. (2) For propellers for which there is no scheduled blade overhaul, at each disassembly of a bearing from a blade for cause, and at intervals not to exceed 5,000 hours' time in service on a blade from the last inspection. (3) Bearing Identification Numbers: BRGS. BRGS. BRGS. BRGS. BRGS. BRGS. 11309 10449/R 16726 16331/R/R 18305/R 4696/R/R 16350 9660/R 15071/R 947/R/R 18328/R 13098 13917/R/R 15337 13345/R 17078/R N16672/R 18077/R N15311 1237/R/R/R 2280/R/R 2847/R/R N8225/R N17430 3670/R/R N13981 N15427 16970/R 11781/R N17368 7801/R/R N14011 16498/R N17313 2629/R N13980 N4629/R 15523/R/R 12825/R N17424 N13977 20448/R 15959/R N17829/R N16327 12794/R N11240/R N15257/R N16078/R N16167/R 5901/R/R 10571 N21240N/R 14731/R N14495/R N16490/R 7060/R/R N9730/R N16898/R 17082/R 5756/R 18119 1298/R N16532 16831/R N18287 3626/R/R 21243 15309/R N18236 18081/R 11766/R 16790 3258/R 16512/R N12714 11838/R/R 9180/R 4416/R 20441/R/R N18094 2489/R 15302/R N10966 N11149 14352/R 3054/R 16339/R N3682/R/R 18055 N15574 N11761 1400/R/R 11751/R/R 16295 N13837 16179/R/R N14938 11346/R/R N13821 14163 7049/R N11778/R/R N13822 4786/R/R/R 14165/R 14734 N13833 1989/R/R 12749/R/R 1851/R/R/R/R N16977/R N20911N 315/R/R 13347/R 9048/R 4709/R N9296 4354/R/R N4689/R 14019/R/R N15489/R 20045N/R N15890 13969 N434/R/R 21280N/R/R 13993/R N20340 N16773 14386/R/R 15567 17018 11764/R 10422/R/R N16706 15220/R 14364/R 10554/R N16647/R 5801/R 2753/R/R 14213/R N15285 11765 N11358/R/R 13559/R/R 16981/R 15275 12038 N21248N/R 12746/R 20449/R/R 15538 11754/R N18103 12571/R/R N15703 N21048N/R 9668 13853/R N15691 20823/R/R 4131/R/R 11756 N16858 5235 5155/R N7479/R N17408 N5007/R/R N11724/R (b) For all other propellers, comply with the following: (1) For propellers for which there is a scheduled blade overhaul - (i) Comply with paragraph (c)(1) at the next disassembly of a bearing from a blade for cause, including disassembly at overhaul; and (ii) Thereafter comply with paragraph (c)(2) at each disassembly of a bearing from a blade for cause, including disassembly at overhaul. (2) For propellers for which there is no scheduled blade overhaul - (i) Comply with paragraph (c)(1) at the next disassembly of a bearing from a blade for cause or before the accumulation of 5,000 hours' time in service on the propeller from the last inspection, whichever occurs sooner; and (ii) Thereafter comply with paragraph (c)(2) at each disassembly of a bearing from a blade for cause and at intervals not to exceed 5,000 hours' time in service on a blade from the last inspection. (c) Inspect blade bearings in accordance with either subparagraph (1) or (2), as applicable. (1) For the initial inspections required by paragraphs (a) and (b) disassemble the propeller to the stage where the assembly of blades complete with bearings are removed from the hub and inspect each blade bearing in accordance with paragraph (d). (2) For the repetitive inspections required by paragraphs (a) and (b), inspect affected blade bearings in accordance with paragraph (d). (d) Measure and record the bearing torque and the center race spigot mean diameter before and after removal of bearing pre-load; and compute the spigot expansion, in accordance with the procedures specified in Dowty Rotol Service Letter No. SER/SSL/1, dated August 12, 1971, or an FAA-approved equivalent. If the spigot expansion, for a bearing size and blade bearing assembly specified in Columns 1 and 2, respectively, of the following table, is - (1) Equal to or greater than Expansion Value A (Column 4), the bearing assembly, blade, and blade bolt may be returned to service. (2) Less than Expansion Value B (Column 5), remove the bearing assembly, blade, and blade bolt from service and mark them in a manner that will prevent their further use. (3) Less than Expansion Value A, but equal to or greater than Expansion Value B (Column 5), before further operation of the blade, blade bolt, and bearing assembly return the bearing assembly to Dowty Rotol, Inc., Arlington, Virginia, or Dowty-Rotol Ltd., Service Department Cheltenham Road, Gloucester, England, for a load-expansion torque test to determine the remaining service life of the blade and blade bolt. The measurements of bearing torque and the mean spigot diameter before and after removal of the blade bearing preload required by this paragraph must accompany the parts. (Col. 1) Bearing Size (Col. 2) Blade Bearing Assembly (Col. 3) Normal Spigot Expansion (Col. 4) Expansion Value A (Col.5) Expansion Value B RA38965 .0055 RA38965Z to .0050 .0035 RA38965Z-1 .0060 No. 20 RA54100 .0050 RA54100Z to .0040 .0030 RA54100Z-1 .0055 RA57099 .0040 RA57099Z to .0035 .0025 RA57099Z-1 .0045 No. 30 RA22355/1 .0035 RA22355/2 to .0030 .0022 .0040 (e) An inspection performed following any period in service since the last installation of the propeller, may be accepted in lieu of the initial inspection required by paragraph (a) to be performed within the next 400 hours' time in service after the effective date of this AD, if the records of that inspection are submitted to an FAA Maintenance Inspector and he determines that the inspection included a computation of spigot expansion performed in accordance with the procedures specified in paragraph (d) which established that the spigot expansion values were equal to or greater than the applicable Expansion Value A (Column 4) specified in paragraph (d) for the bearing size and blade bearing assembly. This amendment becomes effective March 29, 1972. FOOTER:
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