S-92® HELICOPTER ALERT SERVICE BULLETIN

Telephone: (203) 416-4000 https://customerportal.sikorsky.com (2) Refer to Martin Baker SIL No. 831 for affected side facing utility seat serial numbers. (3) Refer to Martin Baker SIL No. 833 for affected observer seat serial numbers. B. Basis for Material Data Per helicopter. C. Bill of Material NOTE: Referenced parts below are for part(s) inventory of top-level kit(s). For top-level kit ordering, see Procurement Requirements Table. New Part No. Qty Nomenclature Old Part No. Reference MBCS12995 1 Repair Kit, Utility Seat Consisting of: MBCS12834 1 Tube Assembly, Back Main MBCS4148 2 Label Ident Warning P37689 9 in. Scotchmate 25mm Blk Hook P38733 2 Pin, Split 1/16 dia x 0.50 (SP90-C4) P38774 4 Pin, Split 1/16 dia x 0.375 (SP90-C3) P35789 1 Strap, Tie Down MS3367-1-0 MBCS12992 1 Repair Kit, Observer Seat This file contains export controlled information. See WARNING on first page. ASB 92-25-026 S-92 ALERT Basic Issue ▪ March 5/20 SERVICE BULLETIN Page 5 ATA 25-22-05 ONE-TIME INSPECTION Section 2. MATERIAL INFORMATION (Continued) New Part No. Qty Nomenclature Old Part No. Reference Consisting of: MBCS12834 1 Tube Assembly, Back Main MBCS4148 2 Label Ident Warning Seat Attenuated P37689 9 in. Scotchmate 25mm Blk Hook P38774 4 Split Pin 1/16 dia x 0.375 (SP90-C3) P38765 2 Split Pin 5/32 dia x 0.625 (SP90-H5) P35789 1 Strap, Tie Down MS3367-1-0 D. Consumable Material Qty Nomenclature Part No. Source A/R Cheesecloth CCC-C-440, or equivalent (1) A/R Isopropyl alcohol TT-I-735, or equivalent (1) A/R 3M™ Dual Lock SJ3541, or equivalent (1) A/R 3M™ double sided tape No. 468MP, or equivalent (1) * Refer to Martin Baker SIL No. 831 and Martin Baker SIL No. 833. (1) Available through normal supply channels. OBSERVE ALL CAUTIONS AND WARNINGS ON CONTAINERS WHEN USING CONSUMABLES. WHEN APPLICABLE, WEAR NECESSARY PROTECTIVE GEAR DURING HANDLING AND USE. IF A CONSUMABLE IS FLAMMABLE OR EXPLOSIVE, MAKE CERTAIN CONSUMABLE AND ITS VAPORS ARE KEPT AWAY FROM HEAT, SPARK AND FLAME. MAKE CERTAIN FIREFIGHTING EQUIPMENT IS READILY AVAILABLE PRIOR TO USE. FOR ADDITIONAL INFORMATION ON TOXICITY, FLASHPOINT AND FLAMMABILITY OF CHEMICALS, CONSULT YOUR MEDICAL DEPARTMENT OR THE MANUFACTURER OF THE CONSUMABLE. This file contains export controlled information. See WARNING on first page. S-92 ALERT ASB 92-25-026 SERVICE BULLETIN Basic Issue ▪ March 5/20 Page 6 ATA 25-22-05 ONE-TIME INSPECTION Section 3. ACCOMPLISHMENT INSTRUCTIONS A. Prepare helicopter for modification: (1) Turn off all helicopter electrical and hydraulic power. (2) Engage rotor brake. NOTE: Tables 1 and 2 can be used to associate the Martin Baker seat part numbers with Sikorsky part numbers. B. Inspect side facing utility seats (MBCS12410AA001) and observer seats (MBCS12200, and MBCS7301-2) for serial numbers listed in Table 2 of Martin-Baker SIL No. 831 and Martin-Baker SIL No. 833. C. Remove existing placards (06092A01F100-2, 06092A01F100-3, and 06092A01F100-4) from aft side of seat (MBCS12410AA001) as required. D. Review and comply with attached Martin-Baker SIL No. 831 and Martin-Baker SIL No. 833. E. Reinstall previously removed placards (06092A01F100-2, 06092A01F100-3, and 06092A01F100-4) on aft side of seats (MBCS12410AA001) in previously installed location as follows: (1) Clean bonding surface of aft side of seats using cheesecloth (CCC-C-440) and isopropyl alcohol (TT-I-735). NOTE: 3M™ Dual Lock (SJ3541), shall be cut as necessary for best fit. (2) Using 3M™ Dual Lock (SJ3541), install placards (06092A01F100-2, and 06092A01F100- 3) on aft side of seat. (3) Using 3M™ double sided tape (No. 468MP), install placard (06092A01F100-4) on aft side of seat. (4) Using a roller (commercially available), apply firm pressure to placards (06092A01F100-2, 06092A01F100-3, and 06092A01F100-4) to obtain intimate contact to the bonding surface of aft side of seat. F. Inspect for remaining FOD. Clean as required. G. Return helicopter to service. TO PREVENT ELECTRICAL SHOCK OF PERSONNEL OR POSSIBLE DAMAGE TO HELICOPTER COMPONENTS, MAKE SURE TO TURN OFF ALL ELECTRICAL POWER. MAKE SURE ALL FOREIGN OBJECT DEBRIS (FOD) IS REMOVED BEFORE RETURNING HELICOPTER TO SERVICE. This file contains export controlled information. See WARNING on first page. ASB 92-25-026 S-92 ALERT Basic Issue ▪ March 5/20 SERVICE BULLETIN Page 7 ATA 25-22-05 ONE-TIME INSPECTION Section 3. ACCOMPLISHMENT INSTRUCTIONS (Continued) TABLE 1 – S-92 SIDE FACING UTILITY SEAT Supplier Part Number Sikorsky Part Number Kit Part Number MBCS12410AA001 N/A 92276-20022-014 92500-82735-101 92073-95001-015 92500-82011-012 92500-82011-015 92500-82735-105 92073-95001-015 92500-82011-012 92500-82011-015 TABLE 2 – S-92 OBSERVER SEAT Supplier Part Number Supplier/Sikorsky Part Number Assembly Part Number Kit Part Number MBCS7301-2 MBCS12200 92500-02833-041 92500-02833-011 92500-02833-102 This file contains export controlled information. See WARNING on first page. S-92 ALERT ASB 92-25-026 SERVICE BULLETIN Basic Issue ▪ March 5/20 Page 8 ATA 25-22-05 ONE-TIME INSPECTION Section 3. ACCOMPLISHMENT INSTRUCTIONS (Continued) H. Record of compliance: (1) Make helicopter logbook entries to show compliance with this ASB as follows: (a) Make helicopter level logbook entry on form SA7343-15 (Aircraft ASB Release Signoff). (b) When ASB modifies a component that can be removed from this helicopter: 1. Make component log card entries on forms SA7343-22 (Aircraft Component Log Cards) and SA7343-21 (Component Log Cards), as applicable. 2. If a component modified by this ASB does not have a log card and the ASB does not create one, then annotate compliance on the next higher assembly that the component belongs to which does have a log card. NOTE: If access to www.Sikorsky360.com is unavailable, complete attached ALERT SERVICE BULLETIN COMPLIANCE RECORD CARD and return it to Sikorsky Aircraft Corporation. (2) Make an appropriate electronic compliance entry in the E-Notification section at www.Sikorsky360.com. Refer to User Guide located on the www.Sikorsky360.com/E- Notification Search page. This file contains export controlled information. See WARNING on first page. (Fold over and tape closed) SIKORSKY AIRCRAFT CORPORATION FACSIMILE NUMBER (817) 762-6715 EMAIL ADDRESS: product_safety.gr-sik@lmco.com ATTENTION: Gr-SIK, Product_Safety SIKORSKY AIRCRAFT CORPORATION (Fold Up to Arrows) IMPORTANT NOTICE Upon COMPLIANCE with the attached ASB, Sikorsky requests your cooperation in completing and returning this ENTIRE PAGE by MAIL, FAX, or scan & EMAIL. Please fill in the requested information at the bottom of the page, so we may maintain proper records documenting the configuration of your aircraft. This information is useful when determining configuration and effectivity of issues affecting fielded aircraft. This request is in keeping with our policy to assure that our customers receive the latest information applicable for the maintenance of your aircraft. Thank you. ALERT SERVICE BULLETIN: ________________ Compliance Record Card TITLE: ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ OWNER/OPERATOR: _____________________________________________________ SUBMITTED BY: ___________________________ DATE: ____________________ FOLLOWING SERIAL NUMBERS ARE NOT AFFECTED BY THIS ASB ASB HAS BEEN COMPLIED WITH ON HELICOPTER SERIAL NUMBERS: ___________ ___________ ___________ ___________ ___________ ___________ ___________ ___________ ___________ ___________ ___________ ___________ 92-25-026 EQUIPMENT FURNISHINGS – Side Facing Utility Seat – One Time Inspection of Side Facing Utility Seat (MBCS12410AA001) and Observer Seat (MBCS12200, and MBCS7301-2) and Repair with New Tube Assembly if Necessary No Postage Necessary BUSINESS REPLY MAIL FIRST-CLASS MAIL PERMIT NO. 432 BRIDGEPORT CT POSTAGE WILL BE PAID BY ADDRESSEE SIKORSKY AIRCRAFT CORPORATION Commercial Systems and Services Mailstop K100 124 QUARRY ROAD TRUMBULL, CT 06611 U.S.A. ATTENTION: Gr-SIK, Product_Safety Please complete the form on the reverse side and FAX to FACSIMILE NUMBER (817) 762-6715 Or scan and email to: EMAIL ADDRESS: product_safety.gr-sik@lmco.com or fold and return ENTIRE form to Sikorsky Aircraft Corporation 7 1 SPECIAL INFORMATION SPECIAL INFORMATION LEAFLET No. 831 SAFETY ADVISORY NOTICE A. SIKORSKY S-92 UTILITY SEAT MBCS12410 ATTENUATION SYSTEM DEGREDATION OF PERFORMANCE EFFECTIVITY B. This Special Information Leaflet is applicable to Tube Assembly, Back Main MBCS12834 fitted to Martin-Baker crashworthy seats detailed below: MBCS12410AA001 NOTE: See Table 2 below for details of affected seat serial numbers. C1. It was found during dynamic testing of a S-92 utility seat conducted by Martin- Baker with 10° wall deformation applied per AS8049A requirements that the seat became detached from the attachment points on one side and potential for increased lumbar loads was observed. C2. Martin-Baker identified the root cause of the test failure to be changes to the finishing process of Tube Main Back MBCS4109 (a detail of Tube Assy, Back Main MBCS12834) circa July 2012. The change in process resulted in increased surface friction in the direction of seat attenuation. Increased surface friction prevented seat attenuation as required during a crash event. C3. Martin-Baker have conducted a System Safety Risk Assessment (SSRA) in relation to this issue. SSRA conducted indicates the reported issue to present a medium safety risk for a Severity 1 hazard, Hazard Risk Index (HRI) 12 – acceptable with review. 1 of 7 Martin-Baker Aircraft Company Limited Higher Denham, near Uxbridge, Middlesex UB9 5AJ, England Tel: (Reception) +44 (0) 1895 832214 Telefax: +44 (0) 1895 832587 WARNING – This file contains export controlled information subject to the EAR. ECCN 9E991 7 2 Continuation Sheet SPECIAL INFORMATION LEAFLET No. 831 C4. The purpose of this Special Information Leaflet is to: C4.1 Inform Customers of the issue. C4.2 Identify S-92 Utility Seats MBCS12410AA001 where finishing of detail Tube Back Main MBCS4109 (a detail of Tube Assembly, Back Main MBCS12834) has been completed using the changed process which require repair action to be completed. C4.3 Provide recovery actions for identified seats, as recommended by Martin- Baker. D1. Timing for Embodiment of this Instruction D1.1 Customers are requested to locate all fielded and inventoried S-92 Utility Seats MBCS12410AA001 and inspect serial number of each seat against Table 2 below. For each seat identified by serial number listed in Table 2 below, order replacement parts in accordance with instruction in paragraph E1 below. Repair actions detailed in paragraph D2 below shall be completed following receipt of replacement items. NOTE: Seat part and serial number information is marked on identification label affixed to underside of the sitting platform assembly. D2. Work Required WARNING: FOLLOW ALL APPLICABLE WARNINGS AND CAUTIONS IN THE RELEVANT MARTIN-BAKER TECHNICAL MANUAL WHEN UNDERTAKING WORK DEFINED IN THIS SPECIAL INFORMATION LEAFLET. CAUTION: USE APPROPRIATE PERSONAL PROTECTIVE EQUIPMENT (PPE) WHEN UNDERTAKING WORK DEFINED IN THIS SPECIAL INFORMATION LEAFLET. D2.1 Tools and Materials Required: D2.1.1 Tools – standard mechanics set of tools. No special tools, fixtures or equipment required. D2.1.2 Materials – See Martin-Baker technical publication MB570 (Issue 2, dated December 2011 current at SIL No. 831 issue) 2 of 7 This file contains export controlled information. See WARNING on first page. 7 3 Continuation Sheet SPECIAL INFORMATION LEAFLET No. 831 D2.2 Parts Required: Part Number Description Quantity per Seat MBCS12834 Tube Assembly, Back Main 1 MBCS4148 Label Ident Warning 2 P37689 Scotchmate 25mm Blk Hook 9 inches P38733 Pin, Split 1/16 dia x 0.50 (SP90-C4) 2 P38774 Pin, Split 1/16 dia x 0.375 (SP90-C3) 4 P35789 Strap, Tie Down MS3367-1-0 1 Table 1 – Parts Required for SIL831 Repair Actions D2.2.1 Required parts identified in Table 1 above are included in Kit Components Utility Seat Repair, MBCS12995. D2.3 Locate affected seats, remove the seat from the aircraft (if installed) and transfer to an appropriate maintenance facility. NOTE: Seat part and serial number information is marked on identification label affixed to underside of the sitting platform assembly. D2.4 Disassemble the seat in accordance with procedures in Martin-Baker technical publication MB570 to the extent necessary to remove discrepant Tube Assembly, Back Main MBCS12834 (Section 1, pages 301 to 302 inclusive refer). D2.5 Examine all removed components for damage, deterioration and wear in accordance with Martin-Baker technical publication MB570 procedures. Replace components as required. D2.6 Assemble seat with replacement Tube Assembly, Back Main MBCS12834 in accordance with Martin-Baker technical publication MB570 procedures (Section 1, pages 701 to 703 inclusive refer). D2.6.1 With reference to Figure 1 below, attach fastener, 25mm hook P37689 to underside of the top of the main back tube assembly. D2.6.2 With reference to Figure 2 below, attach warning ident label MBCS4148 to either side of the main back tube assembly. D2.6.3 Replace split pins P38733 and P38774 and tie down strap P35789 removed at paragraph D2.4 above with new supply items. D2.7 Complete all checks and operational tests necessary in accordance with Martin-Baker technical publication MB570 procedures in order to recover the seat to operational use. 3 of 7 This file contains export controlled information. See WARNING on first page. 7 4 Continuation Sheet SPECIAL INFORMATION LEAFLET No. 831 D2.8 Using Edding 780 ink pen (white colour), or equivalent, mark legend ‘SIL831 incorporated’ to the underside of the Sitting Platform Assembly MBCS4111 adjacent to identification labels. Seal marking with clear matte acrylic lacquer. D2.9 Discrepant main back tube assemblies MBCS12834 shall be positively destroyed to prevent re-use. Disposal of destroyed discrepant main back tube assemblies MBCS12834 shall be in accordance with local rules. D2.9.1 Discard removed split pins part number P38733 and P38774 and tie down strap P35789 in accordance with local rules. D2.10 Record completion of SIL No. 831 in all applicable engineering documentation for subject seat. E1. Customers are requested to place free of charge purchase orders for Kit Components Utility Seat Repair, part number MBCS12995 (as identified in paragraph D2.2 above) for seats identified in Table 2 via Sikorsky in the first instance quoting SIL No. 831 as reference. 4 of 7 This file contains export controlled information. See WARNING on first page. 7 5 Continuation Sheet SPECIAL INFORMATION LEAFLET No. 831 Part Number Seat Serial Number From Seat Serial Number To MBCS12410AA001 PE1278 PE1286 PE1287 PE1295 PE1296 PE1304 PE1315 PE1317 PE2307 PE2315 PF0235 PF0244 PF0245 PF0254 PF0041 PF0049 PF0060 PF0068 PF0255 PF0263 PF1054 PF1057 PK0486 PK0487 PK0540 PK0547 PK0710 PK0719 PE1355 PE1363 PE1364 PE1372 PE1373 PE1374 PF1405 PF1414 PF1415 PF1424 PH0171 PH0179 PH0978 PH0985 PH1008 PH1015 PH1020 PH1025 PH0180 PH0180 PH0777 PH0784 PH0785 PH0792 PH0805 PH0812 PH0813 PH0820 PH0847 PH0853 PJ1092 PJ1099 PJ1100 PJ1102 PF0789 PF0798 PG1240 PG1247 PG1231 PG1239 PH0001 PH0008 PH0009 PH0016 PH0017 PH0024 PH0025 PH0030 PG1301 PG1308 Table 2 - S-92 Utility Seats, Part Number MBCS12410AA001, Requiring Rework Actions 5 of 7 This file contains export controlled information. See WARNING on first page. 7 6 Continuation Sheet SPECIAL INFORMATION LEAFLET No. 831 Figure 1 – Position of Fastener, 25mm Hook P37689 on Tube Assembly, Back Main MBCS12834 6 of 7 View on underside of seat. 1.50 ± 0.12 long Fastener, 25mm Hook (P37689) 2 places. 5.00 ± 0.12 long Fastener, 25mm Hook (P37689). All dimensions in inches. Seat fabric and harness omitted for clarity. This file contains export controlled information. See WARNING on first page. 7 7 Continuation Sheet SPECIAL INFORMATION LEAFLET No. 831 Figure 2 – Position of Warning Ident Label MBCS4148 (Typical) PSD/831 10th July 2019 Customer enquiries are to be sent to SILEnquiries@martin-baker.co.uk 7 of 7 Bracket, Upper MBCS4214 (RH)/MBCS4215 (LH). All dimensions in inches. Warning Ident. Label MBCS4148 to be positioned without red background showing. This file contains export controlled information. See WARNING on first page. 7 1 SPECIAL INFORMATION SPECIAL INFORMATION LEAFLET No. 833 SAFETY ADVISORY NOTICE A. SIKORSKY S-92 OBSERVER SEAT, POTENTIAL FOR HIGHER LUMBAR LOAD EFFECTIVITY B. This Special Information Leaflet is applicable to Tube Assembly, Back Main MBCS12834 fitted to Martin-Baker crashworthy seats detailed below: MBCS12200 MBCS7301-2 NOTE (1): See Table 2 below for details of affected seat serial numbers. NOTE (2): MBCS7301-2 is a lower level assembly of MBCS12200. C1. It was found during dynamic testing of a wall mounted crashworthy seat conducted by Martin-Baker increased lumbar loads from original qualification data were observed. C2. Martin-Baker identified the root cause of the recorded increased loads to be changes to the finishing process of Tube Main Back MBCS4109 (a detail of Tube Assy, Back Main MBCS12834) circa July 2012. The change in process resulted in increased surface friction in the direction of seat attenuation. Whilst increased surface friction caused the increase in lumbar loads, the loads recorded were within allowable limits. C3. Impact analysis conducted by Martin-Baker following the test has identified that there is a theoretical risk, unconfirmed by test, that the pole mounted S-92 observer seat may exhibit excessive lumbar loads in a crash event with affected Tube Main Back MBCS4109 fitted. Due to the perceived safety risk Martin- Baker have concluded that rework action for the identified seats is required. C3. Martin-Baker have conducted a System Safety Risk Assessment (SSRA) in relation to this issue. SSRA conducted indicates the reported issue to present a medium safety risk for a Severity 1 hazard, Hazard Risk Index (HRI) 12 – acceptable with review. 1 of 7 Martin-Baker Aircraft Company Limited Higher Denham, near Uxbridge, Middlesex UB9 5AJ, England Tel: (Reception) +44 (0) 1895 832214 Telefax: +44 (0) 1895 832587 This file contains export controlled information. See WARNING on first page. 7 2 Continuation Sheet SPECIAL INFORMATION LEAFLET No. 833 C4. The purpose of this Special Information Leaflet is to: C4.1 Inform Customers of the issue. C4.2 Identify S-92 observer seats where finishing of detail Tube Back Main MBCS4109 (a detail of Tube Assembly, Back Main MBCS12834) has been completed using the changed process which require repair action to be completed. C4.3 Provide recovery actions for identified seats, as recommended by Martin- Baker. D1. Timing for Embodiment of this Instruction D1.1 Customers are requested to locate all fielded and inventoried S-92 observer seats (MBCS12200/MBCS7301-2) and inspect serial number of each seat against Table 2 below. For each seat identified by serial number listed in Table 2 below, order replacement parts in accordance with instruction in paragraph E1 below. Repair actions detailed in paragraph D2 below shall be completed following receipt of replacement items. NOTE (1): Seat part and serial number information is marked on identification label affixed to underside of the sitting platform assembly. NOTE (2): Quantity 4 seats listed in Table 2 below were sold as, and marked on their identification label as, part number MBCS7301-2 (Seat GA S- 92 Utility Seat). D2. Work Required WARNING: FOLLOW ALL APPLICABLE WARNINGS AND CAUTIONS IN THE RELEVANT MARTIN-BAKER TECHNICAL MANUAL WHEN UNDERTAKING WORK DEFINED IN THIS SPECIAL INFORMATION LEAFLET. CAUTION: USE APPROPRIATE PERSONAL PROTECTIVE EQUIPMENT (PPE) WHEN UNDERTAKING WORK DEFINED IN THIS SPECIAL INFORMATION LEAFLET. 2 of 7 This file contains export controlled information. See WARNING on first page. 7 3 Continuation Sheet SPECIAL INFORMATION LEAFLET No. 833 D2.1 Tools and Materials Required: D2.1.1 Tools – standard mechanics set of tools. No special tools, fixtures or equipment required. D2.1.2 Materials – See Martin-Baker technical publication MB610 (Issue 1, Revision 2, dated June 2019 current at SIL No. 833 issue) D2.2 Parts Required: Part Number Description Quantity per Seat MBCS12834 Tube Assembly, Back Main 1 MBCS4148 Label Ident Warning Seat Attenuated 2 P37689 Scotchmate 25mm Blk Hook 9 inches P38774 Split Pin 1/16 dia x 0.375 (SP90-C3) 4 P38765 Split Pin 5/32 dia x 0.625 (SP90-H5) 2 P35789 Strap, Tie Down MS3367-1-0 1 Table 1 – Parts Required for SIL833 Repair Actions D2.2.1 Required parts identified in Table 1 above are included in Kit Components Observer Seat Repair, MBCS12992. D2.3 Locate affected seats, remove the seat from the aircraft (if installed) and transfer to an appropriate maintenance facility. NOTE (1): Seat part and serial number information is marked on identification label affixed to underside of the sitting platform assembly. NOTE (2): Quantity 4 seats listed in Table 2 below were sold as, and marked on their identification label as, part number MBCS7301-2 (Seat GA S- 92 Utility Seat). D2.4 Disassemble the seat in accordance with procedures in Martin-Baker technical publication MB610 to the extent necessary to remove discrepant Tube Assembly, Back Main MBCS12834 (Section 1, pages 301 to 303 inclusive refer). D2.5 Examine all removed components for damage, deterioration and wear in accordance with Martin-Baker technical publication MB610 procedures. Replace components as required. 3 of 7 This file contains export controlled information. See WARNING on first page. 7 4 Continuation Sheet SPECIAL INFORMATION LEAFLET No. 833 D2.6 Assemble seat with replacement Tube Assembly, Back Main MBCS12834 in accordance with Martin-Baker technical publication MB610 procedures (Section 1, pages 701 to 703 inclusive refer). D2.6.1 With reference to Figure 1 below, attach fastener, 25mm hook P37689 to underside of the top of the main back tube assembly. D2.6.2 With reference to Figure 2 below, attach warning ident label MBCS4148 to either side of the main back tube assembly. D2.6.3 Replace split pins P38774 and P38765 and tie down strap P35789 removed at paragraph D2.4 above with new supply items. D2.7 Complete all checks and operational tests necessary in accordance with Martin-Baker technical publication MB610 procedures in order to recover the seat to operational use. D2.8 Using Edding 780 ink pen (white colour), or equivalent, mark legend ‘SIL833 incorporated’ to the underside of the Sitting Platform Assembly MBCS12215 adjacent to identification labels. Seal marking with clear matte acrylic lacquer. D2.9 Discrepant main back tube assemblies MBCS12834 shall be positively destroyed to prevent re-use. Disposal of destroyed discrepant main back tube assemblies MBCS12834 shall be in accordance with local rules. D2.9.1 Discard removed split pins part number P38774 and P38765 and tie down strap P35789 in accordance with local rules. D2.10 Record completion of SIL No. 833 in all applicable engineering documentation for subject seat. E1. Customers are requested to place free of charge purchase orders for Kit Components Observer Seat Repair, part number MBCS12992 (as identified in paragraph D2.2 above) for seats identified in Table 2 via Sikorsky in the first instance quoting SIL No. 833 as reference. 4 of 7 This file contains export controlled information. See WARNING on first page. 7 5 Continuation Sheet SPECIAL INFORMATION LEAFLET No. 833 Table 2 - S-92 Observer Seats, MBCS12200 and MBCS7301-2, Requiring Rework Action 5 of 7 Part Number (As Sold) Seat Serial Number From Seat Serial Number To B453-00185 B453-00186 C453-00001 C453-00001 C453-00002 C453-00002 B453-00192 B453-00194 B453-00195 B453-00196 B453-00125 B453-00125 B453-00126 B453-00127 B453-00128 B453-00128 B453-00129 B453-00130 B453-00131 B453-00131 B453-00144 B453-00144 B453-00145 B453-00145 B453-00132 B453-00132 B453-00133 B453-00133 B453-00134 B453-00134 B453-00135 B453-00135 B453-00136 B453-00136 B453-00137 B453-00137 B453-00138 B453-00138 B453-00139 B453-00139 B453-00140 B453-00140 B453-00141 B453-00141 B453-00142 B453-00142 B453-00143 B453-00143 B453-00146 B453-00147 B453-00148 B453-00148 B453-00149 B453-00150 B453-00151 B453-00151 B453-00152 B453-00152 B453-00153 B453-00153 B453-00154 B453-00154 B453-00155 B453-00155 B453-00156 B453-00157 B453-00158 B453-00158 B453-00159 B453-00160 B453-00161 B453-00161 B453-00162 B453-00162 B453-00163 B453-00164 B453-00165 B453-00166 B453-00167 B453-00168 B453-00169 B453-00170 B453-00171 B453-00172 B453-00173 B453-00174 B453-00175 B453-00176 B453-00177 B453-00178 B453-00179 B453-00179 B453-00180 B453-00181 B453-00182 B453-00182 B453-00183 B453-00184 B453-00187 B453-00187 B453-00188 B453-00188 B453-00189 B453-00189 B453-00190 B453-00190 B453-00191 B453-00191 MBCS12200 MBCS7301-2 This file contains export controlled information. See WARNING on first page. 7 6 Continuation Sheet SPECIAL INFORMATION LEAFLET No. 833 Figure 1 – Position of Fastener, 25mm Hook P37689 on Tube Assembly, Back Main MBCS12834 6 of 7 View on underside of seat. 1.50 ± 0.12 long Fastener, 25mm Hook (P37689) 2 places. 5.00 ± 0.12 long Fastener, 25mm Hook (P37689). All dimensions in inches. Seat fabric and harness omitted for clarity. This file contains export controlled information. See WARNING on first page. 7 7 Continuation Sheet SPECIAL INFORMATION LEAFLET No. 833 Figure 2 – Position of Warning Ident Label MBCS4148 (Typical) PSD/833 11th July 2019 Customer enquiries are to be sent to SILEnquiries@martin-baker.co.uk 7 of 7 Bracket, Upper MBCS4214 (RH)/MBCS4215 (LH). All dimensions in inches. Warning Ident. Label MBCS4148 to be positioned without red background showing. This file contains export controlled information. See WARNING on first page.