# BAE Systems Inspection Service Bulletin ISB.21-162: Revision 1 - Rights: © BAE Systems. Filed by the FAA in regulations.gov docket FAA-2012-0332; AD 2012-16-08 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [BAE Systems Inspection Service Bulletin ISB.21-162](https://openairdocs.org/service-documents/bae-systems/isb21-162.md) - Title as filed: U.S. DOT/FAA - Service Information - Pages: 14 - PDF: https://openairdocs.org/files/sha256/f2/89/f28955ee49b287b9bb8f7b43361e3319ed18f6915bfd211b8ac8b966e3da0bd7 - Page: https://openairdocs.org/service-documents/bae-systems/isb21-162/file/f28955ee49b2 ## Text This text is 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 (OCR) BAE SYSTEMS (Operations) Limited/ORW, Scotland. Prestwick International Airport, Ayrshire, INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT TRANSMITTAL FOR INSPECTION SERVICE BULLETIN REVISION SERVICE BULLETIN No.ISB.21-162 DATE: 07-JUN-2010 TITLE: AIR CONDITIONING - INSPECTION FOR CRACKING OF SKIN AT FRONT AND REAR DISCHARGE VALVES. REVISION: 1 DATE: 16-SEP-2010 ACTION: 1. Remove and destroy Service Bulletin complete at initial issue. 2. Insert Service Bulletin complete at Revision 1. OVERVIEW OF CHANGES: Minor technical changes to correct sealant identification/application in this service bulletin. INCORPORATION OF THIS REVISION DOES NOT REQUIRE REWORK OF THE MODIFICATION(S) EMBODIED BY EARLIER REVISIONS OF THIS SERVICE BULLETIN. DETAILS OF CHANGES: (1) Para 2. C. (2) - sealant changed to 'PR1422A-2 or PR1764B-2'. (2) Para 2.G. (3) (c) - text changed to read 'PR1764B-2 conductive sealant'. Reference to aluminium powder deleted. (3) Para 2.G. (3) (e) - check for adequate edge sealing added. (4) Para 2.G. (3) (f) - (original f) deleted; alphanumeric of following subparas revised. (5) Para 3.A. (1) - materials table updated to reflect changes. Date: 07-JUN-2010 REVISION TRANSMITTAL SHEET ISB.21-162 Revision: 1 16-SEP-2010 Page 1 of 2 Printed in England ### Page 2 (OCR) BAE SYSTEMS INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT TRANSMITTAL FOR INSPECTION SERVICE BULLETIN REVISION SERVICE BULLETIN No.ISB.21-162 This Page Is Intentionally Left Blank. Date: 07-JUN-2010 REVISION TRANSMITTAL SHEET ISB.21-162 Revision: 1 16-SEP-2010 Page 2 of 2 Printed in England ### Page 3 (OCR) BAE SYSTEMS (Operations) Limited 2RW, Scotland. Prestwick International Airport, Ayrshire, INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT TITLE: AIR CONDITIONING - INSPECTION FOR CRACKING OF SKIN AT FRONT AND REAR DISCHARGE VALVES. 1. Planning information A.Effectivity (1) Aircraft Aircraft affected by this inspection are defined below :- ALL BAe 146 100, 200, 300 Series pre auto-pressurisation modification HCM50259A ALL AVRO 146-RJ70, RJ85, RJ100 Series pre auto-pressurisation modification HCM50259A Check the aircraft technical records for accomplishment of this inspection. B.Reason Moisture ingress into the aluminium/sealant mixture between the water trap/air drier and the fuselage skin adjacent to the front and rear discharge valves has resulted in corrosion build-up. This build-up of corrosion has resulted in cracking of the fuselage skin. C.Description outlets. The bulletin also details the actions necessary to improve corrosion protection. D. CompLiance The technical content of this inspection service bulletin is subject to EASA AIRWORTHINESS DIRECTIVE consultation. The initial external detailed visual inspection per para 2C(1) and any skin repairs necessary are to be accomplished within 12 months of the issue date of this bulletin. Improved corrosion protection (by means of additional edge sealant) per para 2C(2) is to be accomplished at the next maintenance input or within 2 years of the issue date of this bulletin. Date: 07-JUN-2010 ISB. 21-162 Revision: 1 16-SEP-2010 Page 1 of 12 Printed in England ### Page 4 (OCR) BAE SYSTEMS INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT Thereafter repeat external detailed visual inspection will be required every 2 years. If terminating action defined in para 2G is performed then the requirement for repeat inspections is terminated. However, removing the water trap/air drier may damage the fuselage skin, therefore it is recommended that the terminating action should only be carried out if a BAE SYSTEMS approved repair to the skin under the water trap/air drier is required. E. Approval The technical information contained in this document has been approved under the authority of EASA Part 21 Approval No. EASA. 21J.047. F. Manpower 8 hours. This does not include time for sealant curing. G.Materials - cost and availability Cost and Availability is by arrangement between the Operator and BAE SYSTEMS. H.Tooling - cost and availability Cost and Availability is by arrangement between the Operator and BAE SYSTEMS. I.Weight and balance No Effect. J. References Aircraft Maintenance Manual Structural Repair Manual K.Publications affected AMM 21-30-31, 20-10-01 SRM 53-00-00, 53-00-12 L.Electrical load data Not applicable. Date: 07-JUN-2010 ISB. 21-162 Revision: 1 16-SEP-2010 Page 2 of 12 Printed in England ### Page 5 (OCR) BAE SYSTEMS INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT M.Software Accomplishment Summary Not applicable N.Aircraft noise levels Not applicable Date: 07-JUN-2010 ISB. 21-162 Revision: 1 16-SEP-2010 Page 3 of 12 Printed in England ### Page 6 (OCR) BAE SYSTEMS INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT This Page Is Intentionally Left Blank. Date: 07-JUN-2010 ISB.21-162 Revision: 1 16-SEP-2010 Page 4 of 12 Printed in England ### Page 7 (OCR) BAE SYSTEMS INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 2.Accomplishment instructions A. GeneraL (1) The following abbreviations are used within this document :- AMM - Aircraft Maintenance Manual SRM - Structural Repair Manual Observe all WARNINGS and CAUTIONS appearing in the Aircraft Maintenance Manual (AMM) referred to in this Service Bulletin. B.Preparation (1) Open, safety and tag the following circuit breaker (s) :- Table 1. PANEL LABEL/SERVICE GRID REFI IDENT 211-50-30 Dump Ditch Motors F32 211-50-30 Man Pressn Ctrl C32 Refer to AMM 21-30-31 page block 401 and Drawing 1 and locate front and rear discharge valve outlets and water trap/air driers. C.Inspection (1) Perform an external Detailed Visual Inspection (DVI) of the fuselage skin adjacent to the discharge valve outlets (one frame bay check for bulg and surface anomalies and cracking. one stringer above and below to If damage is found, go to para.2.G and perform the Terminating Action. Apply additional PR1422A-2 or PR1764B-2 edge sealant between the water trap/air drier and the fuselage skin to stop any moisture ingress between the water trap/air drier and the skin panel. NOTE: The edge sealant must not contain aluminium. D .Test None. Date: 07-JUN-2010 ISB.21-162 Revision: 1 16-SEP-2010 Page 5 of 12 Printed in England ### Page 8 (OCR) BAE SYSTEMS INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT E.Close up (1) Remove tags and close the following circuit breaker(s) :- Table 2. PANEL LABEL/SERVICE GRID REF/ IDENT 211-50-30 Dump Ditch Motors F32 211-50-30 Man Pressn Ctrl C32 (2) Make certain work area is clean, and clear of tools and miscellaneous equipment. F. Documentation (1) Complete a copy of Inspection Report attached to this Inspection Service Bulletin and return by fax or mail. OR Return all required Inspection Report details via e-mail. G.Terminating Action (1) Remove Water Trap/Air Drier NOTE: Removing the water trap/air drier should only be carried out as part of a BAE SYSTEMS approved repair. (a) Loosen the hose clamp securing the hose to the water trap/air drier and disconnect the hose from the water trap/air drier. (b) Using a non-metallic spatula-type tool and taking care not the aircraft skin, break the adhesion between the trap/air drier and the aircraft skin and remove the water trap/air drier. (2) Repair Aircraft Skin Refer to SRM 53-00-00 for allowable damage. (a) If damage is allowable, repair as detailed in SRM 53-00-12 fig.. 202. NOTE: Make sure the pitching of the repair fasteners does not interfere with the separator re-installation. Date: 07-JUN-2010 ISB.21-162 Revision: 1 16-SEP-2010 Page 6 of 12 Printed in England ### Page 9 (OCR) BAE SYSTEMS INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT (b) If damage is not allowable, contact BAE Systems for a suitable repair. (3) Re-install Water Trap/Air Drier (a) Taking care not to damage the aircraft skin, clean off all traces of old sealant from the water trap/air drier and aircraft skin using a suitable cleaning agent. (b) Ensure the skin in the area beneath the water trap/air drier is free from protective treatment to allow for electrical conductivity. (c) Bond water trap/air drier to aircraft skin using PR1764B-2 conductive sealant. (d) Re-install water trap/air drier so that the angle is as large as possible to allow water to fall to drain. (e) Check for adequate edge sealing once the drier is re-installed. Apply additional PR1422A-2 or PR1764B-2 edge sealant between the water trap/air drier and the fuselage skin to stop any moisture ingress between the water trap/air drier and the skin panel as required. NOTE: The edge sealant must not contain aluminium. (f) Refer to AMM 20-10-01 page block 1 and do an electrical bonding check. (g) Attach the hose to the water trap/air drier and secure using hose clamp. (h) Remove safety clips and tags and close the following circuit breakers Table 3. PANEL LABEL/SERVICE GRID REF/IDENT 211-50-30 DUMP DITCH MOTORS F32 211-50-30 MAN PRESSN CTRL C32 (i) Make certain work area is clean, and clear of tools and miscellaneous equipment. (j) Record accomplishment of terminating action in aircraft records. Date: 07-JUN-2010 ISB.21-162 Revision: 1 16-SEP-2010 Page 7 of 12 Printed in England ### Page 10 (OCR) BAE SYSTEMS INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT FRAME 34 FRAME 23 DA DISCHARGE VALVE (REF) WATER TRAP TYPICAL B SIMILAR HOSE CLAMP AIR DRIER EDGE SEALANT (FREE OF ALUMINIUM POWDER) SHOULD BE APPLIED TO COMPLETE THE SEAL BETWEEN THE AIR DRIERATER TRAP AND THE FUSELAGE SKIN. B2116201 TYPICAL LOCATION OF WATER TRAP/AIR DRIERS DRAWING 1. Date: 07-JUN-2010 ISB.21-162 Revision: 1 16-SEP-2010 Page 8 of 12 Printed in England ### Page 11 (OCR) BAE SYSTEMS INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 3. Material information A. Materials (1) Materials required (Operator supplied). DESCRIPTION MATERIAL NUMBER QTY (REF. AMM 20-20-00 ) PR1422A-2 Sealant 09-002A AR or PR1764B-2 Sealant 09-582 AR NOTE: AR denotes as required. Date: 07-JUN-2010 ISB.21-162 Revision: 1 16-SEP-2010 Page 9 of 12 Printed in England ### Page 12 (OCR) BAE SYSTEMS INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT This Page Is Intentionally Left Blank. Date: 07-JUN-2010 ISB.21-162 Revision: 1 16-SEP-2010 Page 10 of 12 Printed in England ### Page 13 (OCR) BAE SYSTEMS INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT APPENDIX 1 1.INSPECTION REPORT A.Complete and return this form as detailed OPERATOR: AIRCRAFT REGISTRATION: CONSTRUCTORS NUMBER: FLIGHT HOURS: LANDINGS: DATE INSPECTION PERFORMED: FINDINGS: To: Customer Technical Support (Building 37), BAE SYSTEMS (Operations) Limited, Prestwick International Airport, Ayrshire, KA9 2RW, Scotland. Fax + 44 (0) 1292 675432 e-mail raengliaison@baesystems.com Date: 07-JUN-2010 ISB.21-162 Revision: 1 16-SEP-2010 Page 11 of 12 Printed in England ### Page 14 (OCR) BAE SYSTEMS INSPECTION SERVICE BULLETIN BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT This Page Is Intentionally Left Blank. Date: 07-JUN-2010 ISB.21-162 Revision: 1 16-SEP-2010 Page 12 of 12 Printed in England --- 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.