# BAE Systems Service Bulletin 57-JA120141: Revision 1 - Rights: © BAE Systems. Filed by the FAA in regulations.gov docket FAA-2015-2048; AD 2015-16-05 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [BAE Systems Service Bulletin 57-JA120141](https://openairdocs.org/service-documents/bae-systems/57-ja120141.md) - Title as filed: SB 57-JA120141 R1 - Pages: 16 - PDF: https://openairdocs.org/files/sha256/78/3d/783dc35d77fe341fb865c69bf8007b5b93f2e57ae4f52ed5981bfc02ca8a905b - Page: https://openairdocs.org/service-documents/bae-systems/57-ja120141/file/783dc35d77fe ## Text Some pages are OCR from a scan. OCR can misread letters and numbers. Each page's text from the PDF; open the PDF at a page with #page=N. ### Page 1 SERVICE BULLETIN ORIGINAL ISSUE: Jul 31/12 57-JA120141 REVISION 1: Apr 08/14 PAGE 1 OF 1 SERVICE BULLETIN BAE SYSTEMS (OPERATIONS) LIMITED, PRESTWICK INTERNATIONAL AIRPORT, AYRSHIRE, KA9 2RW, SCOTLAND. 57-JA120141 TRANSMITTAL SHEET This page transmits the Revision 1 to Inspection Service Bulletin 57-JA120141. TITLE: INSPECTION OF MAIN LANDING GEAR TRUNNION CAP TENSION BOLTS INSPECTION SERVICE BULLETIN REASON FOR REVISION Inspection Service Bulletin is revised to clarify accomplishment instructions of the Main Landing Gear Trunnion Cap Tension Bolts and parts list. INSTRUCTIONS FOR INCORPORATION Remove and discard entire bulletin pages 1 through 12 at Initial Issue. Add new pages 1 through 12 complete at Revision 1. ### Page 2 (No text on this page.) ### Page 3 ORIGINAL ISSUE: Jul 31/12 57-JA120141 REVISION 1: Apr 08/14 PAGE 1 OF 12 SERVICE BULLETIN BAE SYSTEMS (OPERATIONS) LIMITED, PRESTWICK INTERNATIONAL AIRPORT, AYRSHIRE, KA9 2RW, SCOTLAND. TITLE: INSPECTION OF MAIN LANDING GEAR TRUNNION CAP TENSION BOLTS INSPECTION SERVICE BULLETIN 1. PLANNING INFORMATION A. Effectivity Jetstream Series 3100 and Series 3200 aircraft. B. Reason For aircraft pre-mod JM5218 the Trunnion Cap Tension Lower Bolts MS21250 will have geometric interference between the bolt underhead radius and trunnion cap hole. This could lead to cracking and failure of the bolt. For aircraft post-mod JM5218, in the Illustrated Parts Catalogue (IPC), there is an option to install either 12 point double hex head MS21250 bolts or aircraft spline drive head MS21134 bolts to retain the MLG Trunnion Caps. Both types of bolt have a radius under the head to the shank. The IPC identifies that a countersunk washer is to be used under the head of MS21250 bolts. However, the requirement to fit a countersunk washer under the head of MS21134 has been omitted from the Aircraft Maintenance Manual. There will be geometric interference between the bolt underhead radius and trunnion cap hole if a countersunk washer is not installed. This could lead to cracking and failure of the bolt, which could compromise the structural integrity of the other tension bolts holding the main landing gear in place, resulting in collapse of the main landing gear. C. Description The work covered by this Service Bulletin affects the left and right main landing gear. The tasks are as follows: Pre-Mod JM5218 - Make the aircraft safe for servicing. - Gain access to main landing gear Trunnion Cap Ten sion Bolts. - Identify and remove bolt(s). - Inspect bolt(s) using Magnetic Particle Inspectio n (MPI), to confirm cracks are not present. 57-JA120141 ### Page 4 SERVICE BULLETIN 57-JA120141 ORIGINAL ISSUE: Jul 31/12 PAGE 2 REVISION 1: Apr 08/14 - Re-install crack-free or replacement bolts, with countersunk washers under each bolt head. - Close up. - The aircraft records are amended. Post-Mod JM5218 - Make the aircraft safe for servicing. - Gain access to main landing gear Trunnion Cap Ten sion Bolts. - Visually inspect the Trunnion Cap Bolts to determ ine which type of bolt (head) is installed and washer is installed under each bolt head. - If 12 point double-hex head (MS21250) bolts and w ashers are installed, no further action is required at this time. - If any spline head (MS21134) bolts are found inst alled, remove bolts. - If washers are not installed, remove bolts. - If bolts are being re-installed, inspect bolt(s) using Magnetic Particle Inspection (MPI), to confirm cracks are not present. - Re-install crack-free or replacement bolts, with washers under each bolt head. - Close up. - The aircraft records are amended. D. Manpower 2 man-hours for inspection, (Mechanical skills are necessary). 4 man-hours for removal and installation of bolts and washers, (Mechanical and NDT skills are necessary). E. Material - Cost and Availability For the terms and conditions for the supply of material, Operators are to contact: Jetstream Support, Saywell International, Aviation Centre, Downlands Business Park, Worthing, West Sussex, BN14 9LA, UK. Main: +44(0) 1903 704900 Fax: +44(0) 1903 705761 Email : jetstream@saywell.co.uk F. Tooling - Price and Availability Cost and availability is by arrangement between the Operator and BAE SYSTEMS. ### Page 5 SERVICE BULLETIN ORIGINAL ISSUE: Jul 31/12 57-JA120141 REVISION 1: Apr 08/14 PAGE 3 G. Weight and Balance None. H. Aircraft Noise Levels Not affected. I. Electrical Load Data Not affected. J. Software Accomplishment Summary Not applicable. K. References - Aircraft Maintenance Manual. - Illustrated Parts Catalogue. - Non-Destructive Inspection Manual. L. Publications Affected - Aircraft Maintenance Manual. - Illustrated Parts Catalogue. Operators are requested to advise the Business Support Team, Technical Publications, BAE SYSTEMS (Operations) Limited, Prestwick International Airport, Ayrshire, KA9 2RW, SCOTLAND. of the accomplishment of this service bulletin and request the necessary revisions for the affected manuals. M. Family Tree Of Modification Relationships Not applicable. ### Page 6 SERVICE BULLETIN 57-JA120141 ORIGINAL ISSUE: Jul 31/12 PAGE 4 REVISION 1: Apr 08/14 N. Approval This Service Bulletin must be accomplished within 500 landings from the original issue date. Any bolt that is found to be cracked must be replaced before further flight. If a bolt is not available to replace an existing bolt that is too short to be installed with a countersunk washer under the head, then the existing bolt may be re-installed without a washer, subject to a 500 landing repeat MPI for up to 2000 landings, after which it must be replaced with a longer bolt and countersunk washer. The technical content of this Service Bulletin is be the subject of EASA Airworthiness Directive consultation. The technical content of this Service Bulletin is approved under the authority of EASA PART 21 Approval No. EASA.21J.047. ### Page 7 SERVICE BULLETIN ORIGINAL ISSUE: Jul 31/12 57-JA120141 REVISION 1: Apr 08/14 PAGE 5 2. ACCOMPLISHMENT INSTRUCTIONS WARNING: MAKE SURE THE AIRCRAFT AND THE AIRCRAFT SY STEMS ARE MADE SAFE AS DETAILED IN THE APPLICABLE CHAPTERS OF THE AIRCRAFT MAINTENANCE MANUAL. NOTE: Abbreviations used in the accomplishment inst ructions of this service bulletin are: AMM - Aircraft Maintenance Manual. NDI - Non-Destructive Inspection Manual. A. Preparation (1) Refer to AMM Chapter 24. Remove electrical pow er from the aircraft and display “POWER OFF” notices. (2) Place a warning placard in the flight compartme nt to prevent operation of the landing gear. (3) If the need to replace any bolt is identified r aise aircraft on jacks as detailed in AMM Chapter 7. B. Accomplishment For aircraft Pre-Mod JM5218 (1) Refer to Figures 1 and 2, identify the Trunnion Cap Tension Bolts. (2) Remove bolts MS21250 i.a.w. AMM 32-10-11 – only one bolt per side affected. (3) Inspect bolts using Magnetic Particle Inspectio n i.a.w. NDI Part 5, 20-05-01, to confirm cracks are not present. (4) Re-install crack-free or replacement bolts toge ther with countersunk washers i.a.w. AMM 32-10-11. For 3/8 in. dia. bolts washer PKS1000-6-2-S are to be used. For 7/16 in. dia. Bolts, washer PKS1000-7-2-S are to be used. For aircraft Post-Mod JM5218 (1) Refer to Figures 1 and 2, visually inspect the Trunnion Cap Tension Bolts to determine which type of bolt is installed. (2) If 12 point double-hex head MS21250 bolts are i nstalled and countersunk washers are evident under each bolt head, no further action is required at this time. (3) If any bolts are to be removed, then they shoul d be removed and replaced one at a time, (i.e. at least 3 bolts should be installed at all times). (4) If any spline head MS21134 bolts are found inst alled, or MS21250 bolts are installed without countersunk washers, remove bolts i.a.w. AMM 32-10-11. (a) Refer to Figure 1 and paragraph 3.B. If the exi sting bolts are spline head MS21134, these must be removed and discarded. The existing MS21134 parts are not long enough to allow countersunk washers to be fitted. As replacements ### Page 8 SERVICE BULLETIN 57-JA120141 ORIGINAL ISSUE: Jul 31/12 PAGE 6 REVISION 1: Apr 08/14 to be installed, MS21250 or (longer) MS21134 are new bolts, Magnetic Particle Inspection is not required. NOTE: If a bolt is not available to replace an exis ting bolt that is too short to be installed with a countersunk washer under the head, then the existing bolt me be re-installed without a washer, subject to a 500 landing repeat MPI for up to 2000 landings, after which it must be replaced with a longer bolt and countersunk washer. (b) If the existing bolts are 12 point double-hex h ead MS21250 and these bolts are to be re-installed, inspect bolt(s) using Magnetic Particle Inspection i.a.w. NDI Part 5, 20-05-01, to confirm cracks are not present. (5) Re-install crack-free or replacement bolts and countersunk washers iaw AMM 32- 10-11. C. Recovery (1) Remove the warning placard placed in the flight compartment to prevent operation of the landing gear while the inspections were done. (2) Refer to AMM Chapter 24. Restore electrical po wer to the aircraft and remove “POWER OFF” notices. (3) Refer to AMM Chapter 7. Lower the aircraft off the jacks if required. (4) Add Service Bulletin number ‘32-JA120141’ to th e aircraft records. NOTE: Operators are reminded of the necessity to in form the Business Support Team, Technical Publications, BAE SYSTEMS (Operations) Limited, Prestwick International Airport, Ayrshire, KA9 2RW, SCOTLAND. of the accomplishment of this service bulletin in order to obtain the necessary revisions for the affected manuals, see paragraph 1.L. Publications Affected, of this bulletin. ### Page 9 (OCR) BRITISH AEROSPACE JETSTREAM SERIES 3100 & 3200 SERVICE BULLETIN FWD REAR SPAR DATUM LEFT HAND SHOWN RIGHT HAND OPPOSITE ONLY THIS BOLT AFFECTED SECTION 'C-C' SECTION 'B-B' WASHER PRE MOD JM5218 PRE MOD JM5218 PKS1000-7-2-S (4 POSITIONS) BARREL NUT (4 POSITIONS) SPECIAL BOLT (4 POSITIONS) BOLT (MS21250) BOLT (MS21134) BEARING JOURNAL FORWARD SECTION 'C-C' BEARING JOURNAL REAR SECTION 'B-B' (REF) POST MOD JM5218 (REF) POST MOD JM5218 J3210018 MAIN LANDING GEAR TRUNNION CAP BOLTS FIGURE 1 ORIGINAL ISSUE: Jul 31/12 57-JA120141 REVISION 1: Apr 08/14 PAGE 7 ### Page 10 (OCR) BRITISH AEROSPACE JESTREAM SERIES 2100 & 7200 SERVICE BULLETIN CHECK AIRCRAFT MOD STATE FROM RECORDS OR BY VISUAL INSPECTION PER FIGURE 1 REMOVE 1 OFF BOLT PER WING NO A/C IS POST YES CHECK BOLT TYPE PER FIGURE 1 MOD JM5218 PER FIGURE 1 SECTION B-B VIEW D PRE-MOD JM5218 YES BOLT TYPE IS MS21134 INSPECT BOLT (MPI) NO CHECK EACH WING MEASURE BOLT FOR WASHERS DIAMETER UNDER BOLT HEADS PER FIGURE 1 SECTIONS B-B DISCARD BOLTS REMOVE AND POST-MOD JM5218 AND C-C - ONE AT A TIME INSTALL SERVICEABLE BOLT OF THE SAME WASHER DIAMETER WITH CSK FITTED YES WASHER PER 3.B. UNDER HEAD PRE-MOD JM5218 OF ALL 4 PARTS LIST BOLTS NO REMOVE BOLTS WITHOUT WASHERS - ONE AT A TIME INSTALL SERVICEABLE WASHER PER 3.B. BOLT WITH CSK INSPECT BOLT (MPI) POST-MOD JM5218 PARTS LIST END J5700056 ACCOMPLISHMENT FLOW CHART FIGURE 2 57-JA120141 ORIGINAL ISSUE: Jul 31/12 PAGE 8 REVISION 1: Apr 08/14 ### Page 11 SERVICE BULLETIN ORIGINAL ISSUE: Jul 31/12 57-JA120141 REVISION 1: Apr 08/14 PAGE 9 3. MATERIAL INFORMATION A. New parts supplied as a material kit None. B. Replacement Parts - Operators Supply Old Part No. New Part No. QTY Keyword Post-mod JM5218 MS21134H07045 or MS21250H07046 MS21250H07046 or MS21134H07046 A/R MLG Trunion Cap Tension Bolt MS21134H07059 or MS21250H07060 MS21250H07060 or MS21134H07060 A/R MLG Trunion Cap Tension Bolt PKS1000-7-2-S A/R Countersunk Washer for 7/16 in. d ia. Bolts For Pre-mod JM5218 MS21250H06040 MS21250H06040 A/R MLG Trunion Cap Ten sion Bolt PKS1000-6-2-S 2 Countersunk Washer for 3/8 in. dia. Bolts or MS21250H07040 MS21250H07040 A/R MLG Trunion Cap Ten sion Bolt PKS1000-7-2-S 2 Countersunk Washer for 7/16 in. dia . Bolts C. Instruction Dispositions Notes None. ### Page 12 SERVICE BULLETIN 57-JA120141 ORIGINAL ISSUE: Jul 31/12 PAGE 10 REVISION 1: Apr 08/14 BLANK PAGE ### Page 13 SERVICE BULLETIN ORIGINAL ISSUE: Jul 31/12 57-JA120141 REVISION 1: Apr 08/14 PAGE 11 4. CONTINUED AIRWORTHINESS A. Continued Airworthiness Instructions There are no continued airworthiness instructions applicable to this service bulletin. B. Scheduled Maintenance (1) Not applicable. C. Removal Procedures (1) Not applicable. D. Installation Procedures (1) Not applicable. E. Test Procedures (1) Not applicable. F. Trouble Shooting (1) Not applicable. ### Page 14 SERVICE BULLETIN 57-JA120141 ORIGINAL ISSUE: Jul 31/12 PAGE 12 REVISION 1: Apr 08/14 BLANK PAGE ### Page 15 ACCOMPLISHMENT REPORT SERVICE BULLETIN NUMBER 57-JA120141 TITLE: INSPECTION OF MAIN LANDING GEAR TRUNNION CAP TENSION BOLTS TO: BUSINESS SUPPORT TEAM, TECHNICAL PUBLICATIONS, BAE SYSTEMS (OPERATIONS) LIMITED, PRESTWICK INTERNATIONAL AIRPORT, AYRSHIRE, KA9 2RW, SCOTLAND. Telephone: (01292) 675207 Fax: (01292) 675704 E-mail: RAPublications@baesystems.com PLEASE BE ADVISED THAT THE ABOVE SERVICE BULLETIN HAS BEEN EMBODIED ON AIRCRAFT CONSTRUCTORS NUMBER(S): WE REQUEST THE APPROPRIATE REVISIONS TO APPLICABLE MANUALS. NAME: ...........….................................................................... SIGNED: ............................................................................... COMPANY: ...............…........................................................ DATE: ..................................................…............................. SERVICE BULLETIN COMMENTS/FEEDBACK Please report any non-technical comments or inaccuracies regarding this service bulletin to the above address. ### Page 16 (No text on this page.) --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain, except the copies of manufacturers’ service documents, which belong to their rights holders.