# BAE Systems Service Bulletin J41-52-064: No revision named, from page 13 - Rights: © BAE Systems. Filed by the FAA in regulations.gov docket FAA-2011-0911; AD 2011-25-07 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [BAE Systems Service Bulletin J41-52-064](https://openairdocs.org/service-documents/bae-systems/j41-52-064.md) - Title as filed: U.S. DOT/FAA - Service Bulletin J41-52-064 - Pages: 20 - PDF: https://openairdocs.org/files/sha256/88/0d/880d60c1908ffb639b3db209d88e8ed2548ba2754d6dd03b71b9f128efe2fc32 - Page: https://openairdocs.org/service-documents/bae-systems/j41-52-064/file/880d60c1908f ## 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 13 (OCR) BAe JETSTREAM Series 4100 SERVICE BULLETIN (3) Inspection Procedure (a) Place the probe on the surface of the component within the area of inspection and scan the hatched area shown in figure 2. (b) Monitor the amplitude of the backwall echo at 8 on the timebase, and also look for possible fault indications at approximately 6 on the timebase. (c) Ensure that the upper and lower guide plates on the forward and aft door frames are inspected. NOTE: As the probe is scanned across the cross drilled holes the backwall echo will reduce below the alarm trigger threshold. This is not a fault indication. G. Interpretation (1) A split in the component caused by exfoliation corrosion is likely to occur flush with the upper surface of its base. This will cause a decrease in the backwall echo. It may also produce a fauit signal at approximately 6 on the timebase. H. Accept / Reject Criteria (Ref. Fig. 3) (1) The following shall be considered as evidence of exfoliation corrosion: (a) Any decrease in the backwall echo below 60 per cent full screen height. (b) Any fault signal above 10 per cent full screen height. (c) If evidence of exfoliation corrosion is found in steps (a) or (b). Then the component being inspected is to be replaced with a serviceable component before next flight. Examination Standard (1) All corrosion and discontinuity indications are to be recorded in the relevant aircraft documentation and the appropriate BAE SYSTEMS approved repair / rectification taken. NOTE: The word discontinuity is a generic term for faults such as cracks, corrosion and mechanical damage. Reporting Procedure (1) Report all cracks / discontinuities to: Fleet Data Department (Building 37) BAE SYSTEMS Regional Aircraft Prestwick International Airport Ayrshire Scotland KA9 2RW. ORIGINAL ISSUE: SEP 15/09 J41-52-064 PAGE 11 Printed in the U.K. ### Page 14 (OCR) BAe JETSTREAM Series 4100 SERVICE BULLETIN (2) Also send the following information: (a) Aircraft construction number (D) Aircraft registration (c) Flying hours and number of landings (d) SB number (e) Location / area or length of the crack or discontinuity / per cent FSH. K. Additional Information (1) Ensure all test equipment is removed from the aircraft on completion of work. J41-52-064 ORIGINAL ISSUE: SEP 15/09 PAGE 12 Printed in the U.K. ### Page 15 (OCR) BAe JETSTREAM Series 4100 SERVICE BULLETIN REMOVE STAINLESS STEEL GUIDE UPPER GUIDE PLATE REMOVE STAINLESS STEEL GUIDE LOWER GUIDE PLATE FLOOR LEVEL GUIDE PLATES FITTED TO AFT DOOR FRAME SHOWN GUIDE PLATES FITTED TO FORWARD DOOR FRAME ARE SIMILAR Location of Passenger Door Upper and Lower Guide Plates Figure 1 ORIGINAL ISSUE: SEP 15/09 J41-52-064 PAGE 13 Printed in the U.K. ### Page 16 (OCR) BAe JETSTREAM Series 4100 SERVICE BULLETIN POSITION PROBE AT THIS POINT TO SET BACKWALL ECHO CROSS DRILLED HOLES UPPER GUIDE PLATE CROSS DRILLED HOLES POSITION PROBE AT THIS POINT TO SET BACKWALL ECHO CROSS DRILLED HOLES - CROSS DRILLED HOLES LOWER GUIDE PLATE SCAN HATCHED AREA GUIDE PLATES FITTED TO AFT DOOR FRAME SHOWN GUIDE PLATES FITTED TO FORWARD DOOR FRAME ARE SIMILAR Scan Areas - Upper and Lower Guide Plates Figure 2 J41-52-064 ORIGINAL ISSUE: SEP 15/09 PAGE 14 Printed in the U.K. ### Page 17 (OCR) BAe JETSTREAM Series 4100 SERVICE BULLETIN TYPICAL EXFOLIATION BACKWALL ECHO CORROSION ECHO 100 60 GATE 2 THRESHOLD SET AT 60 PER CENT FULL SCREEN HEIGHT GATE 1 THRESHOLD SET AT 10 PER CENT FULL SCREEN HEIGHT 0.43" (11 mm) 0.31" (8mm) 0.35" (9mm) Krautkramer 5MHz, 0 degree contact probe 0.39" (10mm) Part number K5K from GE Inspection Typical Screen Display and Ultrasonic Probe Figure 3 ORIGINAL ISSUE: SEP 15/09 J41-52-064 PAGE 15 Printed in the U.K. ### Page 18 (No text on this page.) ### Page 19 (OCR) BAE SYSTEMS ACCOMPLISHMENT REPORT SERVICE BULLETIN NUMBER J41-52-064 TITLE: DOORS - INTRODUCTION OF ULTRASONIC INSPECTION OF THE UPPER AND LOWER PASSENGER/CREW DOOR PIN GUIDES TO: THE PUBLICATIONS CONTROL TEAM, AIRCRAFT MAINTENANCE & PUBLICATION SERVICES, BAE SYSTEMS, 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. BAE SYSTEMS (Operations) Limited. Printed in the U.K ### Page 20 (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.