AD 93-25-02
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bombardier Inc. | DHC-8-101 | Airworthiness Directives; De Havilland Models DHC-8-100 and DHC-8-300 Series Airplanes |
| aircraft | Bombardier Inc. | DHC-8-102 | Airworthiness Directives; De Havilland Models DHC-8-100 and DHC-8-300 Series Airplanes |
| aircraft | Bombardier Inc. | DHC-8-103 | Airworthiness Directives; De Havilland Models DHC-8-100 and DHC-8-300 Series Airplanes |
| aircraft | Bombardier Inc. | DHC-8-106 | Airworthiness Directives; De Havilland Models DHC-8-100 and DHC-8-300 Series Airplanes |
| aircraft | Bombardier Inc. | DHC-8-301 | Airworthiness Directives; De Havilland Models DHC-8-100 and DHC-8-300 Series Airplanes |
| aircraft | Bombardier Inc. | DHC-8-311 | Airworthiness Directives; De Havilland Models DHC-8-100 and DHC-8-300 Series Airplanes |
| aircraft | Bombardier Inc. | DHC-8-315 | Airworthiness Directives; De Havilland Models DHC-8-100 and DHC-8-300 Series Airplanes |
Unsafe Condition
Cracks in the splined couplings of flap primary-drive torque tubes could cause asymmetrical flap deployment.
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Required Actions
Inspect flap primary-drive torque tubes for specific part numbers and serial numbers listed in TABLE 1. If installed, remove through-bolts and inspect for cracks using a 10X magnifying glass. Replace cracked splined couplings or torque tubes as specified in Sundstrand Service Bulletins. Conduct recurring inspections at intervals not exceeding 300 hours time-in-service. Perform operational checks of torque sensors and install specified modifications within 2,000 hours time-in-service or 9 months.
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Compliance Time
Within 300 hours time-in-service after January 19, 1994, and recurring intervals as specified.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Bombardier Inc. models DHC-8-101, DHC-8-102, DHC-8-103, DHC-8-106, DHC-8-301, DHC-8-311, DHC-8-315 with serial numbers 3 through 293.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Flap Primary-Drive Torque Tubes
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_93-25-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 93-25-02 Document Type: AD Final Rules Docket Number: 90-NM-129-AD Subject Heading: Airworthiness Directives; De Havilland Models DHC-8-100 and DHC-8-300 Series Airplanes Subject: Flap Primary-Drive Torque Tubes Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/19/1994 Make: Bombardier Inc. Model: DHC-8-101 | DHC-8-102 | DHC-8-103 | DHC-8-106 | DHC-8-301 | DHC-8-311 | DHC-8-315 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: AIRWORTHINESS DIRECTIVES FINAL RULES: 93-25-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-129-AD AMENDMENT: 39-8768 AD NUMBER: 93-25-02 SUBJECT HEADING: Airworthiness Directives; De Havilland Models DHC-8-100 and DHC-8-300 Series Airplanes ACTION: SUMMARY: DATES: Effective January 19, 1994. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 93-25-02 DE HAVILLAND: Amendment 39-8768. Docket 90-NM-129-AD. Applicability: Model DHC-8-100 and DHC-8-300 series airplanes, having serial numbers 3 through 293, certificated in any category. Compliance: Required as indicated, unless accomplished previously. To prevent asymmetrical flap deployment, accomplish the following: (a) For airplanes having serial numbers 3 through 231, 233, 235, 237, and 243: Within 300 hours time-in-service after the effective date of this AD, accomplish the procedures specified in paragraphs (a)(1), (a)(2), (a)(3), and (a)(4) of this AD: (1) Locate and inspect the flap primary-drive torque tubes to determine if parts having the part numbers (P/N) and serial numbers (S/N) listed in TABLE 1, below, are installed. TABLE 1 Torque Tube P/N Series Torque Tube S/N 734187 125 through 171 734378 129 through 150 734380 127 through 166 734382 211 through 322 734384 153 through 188 and 226 through 235 734386 195 through 286 734388 160 through 177 (2) If any torque tube listed in TABLE 1 is installed, prior to further flight, remove the through-bolt from the splined coupling on each end of the torque tube and, using a 10X magnifying glass, perform a detailed visual inspection of the area around the bolt holes for cracks. (3) If a splined coupling is found to be cracked on a particular torque tube, prior to further flight, accomplish either paragraph (a)(3)(i) or (a)(3)(ii) of this AD: (i) Replace the splined couplings on that torque tube in accordance with the accomplishment instructions in the appropriate Sundstrand Service Bulletin specified in TABLE 2, below, and re-identify the torque tube as indicated. Marking the service bulletin number on the rod with indelible ink will satisfy this re-identification requirement. Or (ii) Replace the particular torque tube with a serviceable unit. NOTE: Some torque tubes have one splined coupling, while others have two. TABLE 2 Torque Tube P/N Series Sundstrand Alert Service Bulletin No. Post-Modification Identification 734187 734187-27-A2, Rev. 1, dated September 15, 1990 27-A2 734378 734378-27-A3, Rev. 1, dated January 25, 1991 27-A3 734380 734380-27-A2, Rev. 1, dated September 15, 1990 27-A2 734382 734382-27-A3, Rev. 1, dated September 15, 1990 27-A3 734384 734384-27-A2, Rev. 1, dated September 15, 1990 27-A2 734386 734386-27-A2, Rev. 1, dated September 15, 1990 27-A2 734388 734388-27-A1, Rev. 1, dated September 15, 1990 27-A1 (4) Upon reassembly, install the through-bolt, and torque to between 20 and 25 in-lb. (b) For airplanes having serial numbers 3 through 231, 233, 235, 237, and 243: Within 900 hours time-in-service after the effective date of this AD, replace all splined couplings [which have not been replaced in accordance with paragraph (a)(3)(i) or (a)(3)(ii) of this AD] on torque tubes identified in TABLE 1, above, in accordance with the accomplishment instructions in the appropriate Sundstrand Service Bulletin specified in TABLE 2, above. Re-identify the torque tubes as indicated. Marking the service bulletin number on the rod with indelible ink will satisfy this re-identification requirement. (c) For airplanes having serial numbers 3 through 293: Within 300 hours time-in- service after the effective date of this AD, and thereafter at intervals not to exceed 300 hours time-in-service, accomplish the following visual inspection procedure of the flap primary-drive torque tube system and the flap secondary-drive flex shaft system: (1) Extend flaps fully. (2) Conduct a general visual inspection of the flap primary-drive torque tubes over their entire length for fracture, rubbing, and wear. (3) Damaged torque tubes, or torque tubes exhibiting wear greater than 0.010 inch in depth or 180 degrees around the circumference, must be replaced with serviceable torque tubes prior to further flight. (4) Conduct a general visual inspection of the flap secondary-drive flex outer sheath casing for permanent deformation (kinks), or evidence of excessive heat of the outer braided sheath, melting of the outer plastic sheath (if installed), or any discoloration of the anodic film on the casing ferrules. (5) If any of the conditions specified in paragraph (c)(4) of this AD exist, the secondary drive assemblies must be replaced with serviceable units prior to further flight. (d) For airplanes having serial numbers 3 through 293: Within 600 hours time-in- service after the effective date of this AD, unless previously accomplished within the last 600 hours time-in-service; and thereafter at intervals not to exceed 1,200 hours time-in-service; accomplish the procedures specified in paragraphs (d)(1) and (d)(2) of this AD: (1) Perform an operational check of the torque sensor in accordance with the following service documents, as appropriate: (i) For Model DHC-8-100 series airplanes: Maintenance Program Task 2750/11 (refer to DASH 8 Maintenance Program Supplementary Information, PSM 1-8-7, Volume 2, Procedures 27, dated March 30, 1990). (ii) For Model DHC-8-300 series airplanes: Maintenance Program Task 2750/11 (refer to DASH 8 Maintenance Program Supplementary Information, PSM 1-83-7, Volume 2, Procedures 27, dated December 21, 1988). (2) Any torque sensor found malfunctioning or jammed must be replaced with a serviceable unit prior to further flight. (e) For airplanes having serial numbers 3 through 293: Within 2,000 hours time-in- service after the effective date of this AD, or within 9 months after the effective date of this AD, whichever occurs first, modify the wing flap system by installing Modification 8/1473 in accordance with de Havilland Service Bulletin S.B. 8-54-16, Revision 'A', dated October 26, 1990; Modification 8/0803 in accordance with de Havilland Service Bulletin S.B. 8-27-47, Revision 'A', dated July 6, 1990; and Modification 8/1649 in accordance with de Havilland Service Bulletin S.B. 8-27-61, dated October 25, 1991. Installation of these modifications constitutes terminating action for the requirements of paragraphs (c) and (d) of this AD. (f) Installation of Modification 8/1473 in accordance with de Havilland Service Bulletin S.B. 8-54-16, Revision 'A', dated October 26, 1990; Modification 8/0803 in accordance with de Havilland Service Bulletin S.B. 8-27-47, Revision 'A', dated July 6, 1990; and Modification 8/1649 in accordance with de Havilland Service Bulletin S.B. 8-27-61, dated October 25, 1991; constitutes terminating action for the requirements of paragraphs (c) and (d) of this AD. (g) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, New York Aircraft Certification Office (ACO). Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, New York ACO. NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the New York ACO. (h) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. (i) The replacements and re-identification shall be done in accordance with the following Sundstrand Alert service bulletins, which contain the specified effective pages: Service Bulletin Referenced and Date Page Number Revision Level Shown on Page Date Shown on Page 734187-27-A2, Revision 1, September 15, 1990 1-3, 6-7 4-5 1 Original September 15, 1990 October 20, 1989 734378-27-A3, Revision 1, January 25, 1991 1-7 1 January 25, 1991 734380-27-A2, Revision 1, September 15, 1990 1-3, 6-7 4-5 1 Original September 15, 1990 October 20, 1989 734382-27-A3, Revision 1, September 15, 1990 1-3, 6-7 4-5 1 Original September 15, 1990 October 20, 1989 734384-27-A2, Revision 1, September 15, 1990 1-3, 6-7 4-5 1 Original September 15, 1990 October 20, 1989 734386-27-A2, Revision 1, September 15, 1990 1-3, 6-7 4-5 1 Original September 15, 1990 October 20, 1989 734388-27-A1, Revision 1, September 15, 1990 1-3, 6-7 4-5 1 Original September 15, 1990 October 20, 1989 The modifications shall be done in accordance with de Havilland Service Bulletin S.B. 8-54-16, Revision 'A', dated October 26, 1990; de Havilland Service Bulletin S.B. 8-27-47, Revision 'A', dated July 6, 1990; and de Havilland Service Bulletin S.B. 8-27-61, dated October 25, 1991. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from de Havilland, Inc., Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Engine and Propeller Directorate, New York Aircraft Certification Office, 181 South Franklin Avenue, Room 202, Valley Stream, New York; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (j) This amendment becomes effective on January 19, 1994. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_93-25-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 93-25-02 Document Type: AD Final Rules Docket Number: 90-NM-129-AD Subject Heading: Airworthiness Directives; De Havilland Models DHC-8-100 and DHC-8-300 Series Airplanes Subject: Flap Primary-Drive Torque Tubes Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/19/1994 Make: Bombardier Inc. Model: DHC-8-101 | DHC-8-102 | DHC-8-103 | DHC-8-106 | DHC-8-301 | DHC-8-311 | DHC-8-315 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: AIRWORTHINESS DIRECTIVES FINAL RULES: 93-25-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-129-AD AMENDMENT: 39-8768 AD NUMBER: 93-25-02 SUBJECT HEADING: Airworthiness Directives; De Havilland Models DHC-8-100 and DHC-8-300 Series Airplanes ACTION: SUMMARY: DATES: Effective January 19, 1994. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 93-25-02 DE HAVILLAND: Amendment 39-8768. Docket 90-NM-129-AD. Applicability: Model DHC-8-100 and DHC-8-300 series airplanes, having serial numbers 3 through 293, certificated in any category. Compliance: Required as indicated, unless accomplished previously. To prevent asymmetrical flap deployment, accomplish the following: (a) For airplanes having serial numbers 3 through 231, 233, 235, 237, and 243: Within 300 hours time-in-service after the effective date of this AD, accomplish the procedures specified in paragraphs (a)(1), (a)(2), (a)(3), and (a)(4) of this AD: (1) Locate and inspect the flap primary-drive torque tubes to determine if parts having the part numbers (P/N) and serial numbers (S/N) listed in TABLE 1, below, are installed. TABLE 1 Torque Tube P/N Series Torque Tube S/N 734187 125 through 171 734378 129 through 150 734380 127 through 166 734382 211 through 322 734384 153 through 188 and 226 through 235 734386 195 through 286 734388 160 through 177 (2) If any torque tube listed in TABLE 1 is installed, prior to further flight, remove the through-bolt from the splined coupling on each end of the torque tube and, using a 10X magnifying glass, perform a detailed visual inspection of the area around the bolt holes for cracks. (3) If a splined coupling is found to be cracked on a particular torque tube, prior to further flight, accomplish either paragraph (a)(3)(i) or (a)(3)(ii) of this AD: (i) Replace the splined couplings on that torque tube in accordance with the accomplishment instructions in the appropriate Sundstrand Service Bulletin specified in TABLE 2, below, and re-identify the torque tube as indicated. Marking the service bulletin number on the rod with indelible ink will satisfy this re-identification requirement. Or (ii) Replace the particular torque tube with a serviceable unit. NOTE: Some torque tubes have one splined coupling, while others have two. TABLE 2 Torque Tube P/N Series Sundstrand Alert Service Bulletin No. Post-Modification Identification 734187 734187-27-A2, Rev. 1, dated September 15, 1990 27-A2 734378 734378-27-A3, Rev. 1, dated January 25, 1991 27-A3 734380 734380-27-A2, Rev. 1, dated September 15, 1990 27-A2 734382 734382-27-A3, Rev. 1, dated September 15, 1990 27-A3 734384 734384-27-A2, Rev. 1, dated September 15, 1990 27-A2 734386 734386-27-A2, Rev. 1, dated September 15, 1990 27-A2 734388 734388-27-A1, Rev. 1, dated September 15, 1990 27-A1 (4) Upon reassembly, install the through-bolt, and torque to between 20 and 25 in-lb. (b) For airplanes having serial numbers 3 through 231, 233, 235, 237, and 243: Within 900 hours time-in-service after the effective date of this AD, replace all splined couplings [which have not been replaced in accordance with paragraph (a)(3)(i) or (a)(3)(ii) of this AD] on torque tubes identified in TABLE 1, above, in accordance with the accomplishment instructions in the appropriate Sundstrand Service Bulletin specified in TABLE 2, above. Re-identify the torque tubes as indicated. Marking the service bulletin number on the rod with indelible ink will satisfy this re-identification requirement. (c) For airplanes having serial numbers 3 through 293: Within 300 hours time-in- service after the effective date of this AD, and thereafter at intervals not to exceed 300 hours time-in-service, accomplish the following visual inspection procedure of the flap primary-drive torque tube system and the flap secondary-drive flex shaft system: (1) Extend flaps fully. (2) Conduct a general visual inspection of the flap primary-drive torque tubes over their entire length for fracture, rubbing, and wear. (3) Damaged torque tubes, or torque tubes exhibiting wear greater than 0.010 inch in depth or 180 degrees around the circumference, must be replaced with serviceable torque tubes prior to further flight. (4) Conduct a general visual inspection of the flap secondary-drive flex outer sheath casing for permanent deformation (kinks), or evidence of excessive heat of the outer braided sheath, melting of the outer plastic sheath (if installed), or any discoloration of the anodic film on the casing ferrules. (5) If any of the conditions specified in paragraph (c)(4) of this AD exist, the secondary drive assemblies must be replaced with serviceable units prior to further flight. (d) For airplanes having serial numbers 3 through 293: Within 600 hours time-in- service after the effective date of this AD, unless previously accomplished within the last 600 hours time-in-service; and thereafter at intervals not to exceed 1,200 hours time-in-service; accomplish the procedures specified in paragraphs (d)(1) and (d)(2) of this AD: (1) Perform an operational check of the torque sensor in accordance with the following service documents, as appropriate: (i) For Model DHC-8-100 series airplanes: Maintenance Program Task 2750/11 (refer to DASH 8 Maintenance Program Supplementary Information, PSM 1-8-7, Volume 2, Procedures 27, dated March 30, 1990). (ii) For Model DHC-8-300 series airplanes: Maintenance Program Task 2750/11 (refer to DASH 8 Maintenance Program Supplementary Information, PSM 1-83-7, Volume 2, Procedures 27, dated December 21, 1988). (2) Any torque sensor found malfunctioning or jammed must be replaced with a serviceable unit prior to further flight. (e) For airplanes having serial numbers 3 through 293: Within 2,000 hours time-in- service after the effective date of this AD, or within 9 months after the effective date of this AD, whichever occurs first, modify the wing flap system by installing Modification 8/1473 in accordance with de Havilland Service Bulletin S.B. 8-54-16, Revision 'A', dated October 26, 1990; Modification 8/0803 in accordance with de Havilland Service Bulletin S.B. 8-27-47, Revision 'A', dated July 6, 1990; and Modification 8/1649 in accordance with de Havilland Service Bulletin S.B. 8-27-61, dated October 25, 1991. Installation of these modifications constitutes terminating action for the requirements of paragraphs (c) and (d) of this AD. (f) Installation of Modification 8/1473 in accordance with de Havilland Service Bulletin S.B. 8-54-16, Revision 'A', dated October 26, 1990; Modification 8/0803 in accordance with de Havilland Service Bulletin S.B. 8-27-47, Revision 'A', dated July 6, 1990; and Modification 8/1649 in accordance with de Havilland Service Bulletin S.B. 8-27-61, dated October 25, 1991; constitutes terminating action for the requirements of paragraphs (c) and (d) of this AD. (g) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, New York Aircraft Certification Office (ACO). Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, New York ACO. NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the New York ACO. (h) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. (i) The replacements and re-identification shall be done in accordance with the following Sundstrand Alert service bulletins, which contain the specified effective pages: Service Bulletin Referenced and Date Page Number Revision Level Shown on Page Date Shown on Page 734187-27-A2, Revision 1, September 15, 1990 1-3, 6-7 4-5 1 Original September 15, 1990 October 20, 1989 734378-27-A3, Revision 1, January 25, 1991 1-7 1 January 25, 1991 734380-27-A2, Revision 1, September 15, 1990 1-3, 6-7 4-5 1 Original September 15, 1990 October 20, 1989 734382-27-A3, Revision 1, September 15, 1990 1-3, 6-7 4-5 1 Original September 15, 1990 October 20, 1989 734384-27-A2, Revision 1, September 15, 1990 1-3, 6-7 4-5 1 Original September 15, 1990 October 20, 1989 734386-27-A2, Revision 1, September 15, 1990 1-3, 6-7 4-5 1 Original September 15, 1990 October 20, 1989 734388-27-A1, Revision 1, September 15, 1990 1-3, 6-7 4-5 1 Original September 15, 1990 October 20, 1989 The modifications shall be done in accordance with de Havilland Service Bulletin S.B. 8-54-16, Revision 'A', dated October 26, 1990; de Havilland Service Bulletin S.B. 8-27-47, Revision 'A', dated July 6, 1990; and de Havilland Service Bulletin S.B. 8-27-61, dated October 25, 1991. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from de Havilland, Inc., Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Engine and Propeller Directorate, New York Aircraft Certification Office, 181 South Franklin Avenue, Room 202, Valley Stream, New York; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (j) This amendment becomes effective on January 19, 1994. FOOTER:
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