BAE SYSTEMS (Operations) Limited, Prestwick International Airport, Ayrshire, KA9 2RW, Scotland. 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

TRANSMITTAL FOR INSPECTION SERVICE BULLETIN REVISION 

SERVICE BULLETIN No.ISB. 53-239 

DATE: 13-JUN-2012 

TITLE: FUSELAGE - INSPECTION OF REAR FUSELAGE AFT SKIN LAP JOINTS FOR 

CRACKING. 

REVISION: 3 DATE: 07-MAY-2014 

ACTIONS 

(1) Remove and discard Inspection Service Bulletin complete at 

revision 2. 

(2) Insert Inspection Service Bulletin complete at revision 3. 

REASONS FOR REVISION 

(1) Areas not to be inspected clarified for aircraft with Large freight doors (see para.1.C and para.2.C.(1)). 

(2) EASA Airworthiness Directive reference added (see para.1 .D). 

(3) Editorial. 

INCORPORATION OF THIS REVISION DOES NOT REQUIRE INSPECTIONS 

ADDITIONAL TO THOSE DONE AT PREVIOUS REVISIONS OF THIS 

INSPECTION SERVICE BULLETIN. 

Date: 13-JUN-2012 REVISION TRANSMITTAL SHEET 

ISB. 53-239 

Revision: 3 07-MAY-2014 Page 1 of 2 

Pr inted in England 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

TRANSMITTAL FOR INSPECTION SERVICE BULLETIN REVISION 

SERVICE BULLETIN No.ISB. 53-239 

This Page Is Intentionally Left Blank. 

Date: 13-JUN- 2012 

Revision: 3 07-MAY-2014 

Printed in England 

REVISION TRANSMITTAL SHEET 

ISB. 53-239 

Page2of2 
BAE SYSTEMS (Operations) Limited, Prestwick International Airport, Ayrshire, 

KA9 2RW, Scotland. 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

TITLE: FUSELAGE - INSPECTION OF REAR FUSELAGE AFT SKIN LAP JOINTS FOR 

CRACKING. 

1.Planning information 

A.Effectivity 

(1) Aircraft 

Aircraft affected by this inspection are defined below:-

BAe 146-301 

All BAe 146-100, 200, 300 Series 

All AVRO 146-RJ70, RJ85, RJ100 Series 

Check the aircraft technical records for accomplishment of 

this inspection before actioning this Inspection Service 

Bulletin (ISB). 

B.Reason 

During climb-out, an AVRO 146-RJ100 recently experienced 

pressurization problems. Subsequent investigation identified a 

42.87 in. (1089 mm.) Long crack in the rear fuselage aft Lower 

skin at the Lap joint at stringer 30 Left. In addition to the skin 

crack, cracks were found in Frames 41X and 42. 

Existing fatigue inspections of the fuselage skin may not detect a 

crack growing in this area, which could affect the structural 

integrity of the rear fuselage. 

Consequently, fleet wide inspection of the rear fuselage skin Lap 

joints is required. 

C.Description 

An external eddy current inspection is performed on the rear 

fuselage aft skin Lap joints at stringers 11, 18 and 30 Left and 

right and stringer 2 right, between frame 39Y and frame 44. 

Inspection aft of frame 44 is not required. 

NOTE: There may be external skin repair plates fitted to the 

aircraft which obscure the areas subject to inspection or 

impede the inspection process. These areas are not to be 

inspected but must be reported to BAE SYSTEMS using the 

reporting form provided in Appendix 1 of this ISB. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

ISB. 53-239 

Page1of12 
I 

BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

NOTE: For BAe 146-100, BAe 146-200 and BAe 146-300 aircraft with 

Large freight doors, Lap joints 11 and 18 Left forward of 

frame 43, and Lap joint 2 right forward of frame 42, are 

obscured by the Large freight door surround skin doublers. 

These areas are not to be inspected (see Drawing 2). 

If cracks, corrosion or any other defects are found, contact BAE 

SYSTEMS for an approved repair scheme. 

D.Compliance 

This ISB, at Revision 2, is the subject of EASA Airworthiness 

Directive 2013-0207. Compliance with this ISB, at Revision 3, is 

to be in accordance with the table below:-

Table 1. 

Skin Land Initial Inspection, Repeat Interval, Repeat Interval, 

All Aircraft RJ Delta P Aircraft 146 and RJ Pre Delta 

(Mod HCM50070E or F P Aircraft (Pre-Mod 

or HCM50259A) HCM50070E or F or 

Pre-Mod HCM50259A) 

Stringer 30, Left 10,000 FC 4,000 FC 7,500 FC 

and Right 

Stringer 2, Right 10,000 FC 4,000 FC 7,500 FC 

Stringer 11, Left 10,000 FC 4,000 FC 7,500 FC 

and Right 

Stringer 18, Left 10,000 FC 4,000 FC 7,500 FC 

and Right 

NOTE: FC is defined as Flight Cycles. 

For aircraft that have accumulated more than 9000 Flight Cycles 

since entry into service, initial inspection is to be within 1000 

Flight Cycles or 6 months, whichever is earlier. 

Inspections previously performed in accordance with this ISB at 

initial issue or EASA AMOC 10041592 may be claimed, but only as 

the initial inspections for the skin Lands at Stringer 30 Left and 

Stringer 30 Right. 

Thereafter, all Stringers are to be inspected at the repeat 

intervals specified in the table. 

E.Approval 

The technical information contained in this document has been 

approved under the authority of EASA Part 21 Approval No. 

EASA.21J.047. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

ISB. 53-239 

Page2of12 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

F.Manpower 

To inspect as defined in para. 2 - 8.0 man-hours per aircraft. 

This man-hour estimate does not include time for gaining access to 

the inspection area. 

G.Materials- cost and availability 

Not applicable. 

H.Tooling- cost and availability 

Appropriate staging/access platforms are required to allow close 

inspection of all the rear fuselage aft skin Lap joints. 

Refer to Appendix 2, EQUIPMENT AND MATERIALS. 

!.Weight and balance 

Not applicable. 

J .References 

Aircraft Maintenance Manual AMM 12-10-24. 

K.Publications affected 

Not applicable. 

L.Electrical Load data 

Not applicable. 

M.Software accomplishment summary 

Not applicable. 

N.Aircraft noise Levels 

Not applicable. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Prin t ed in Eng l and 

ISB. 53-239 

Page3of12 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

This Page Is Intentionally Left Blank. 

Date: 13-JUN-2012 ISB. 53-239 

Revision: 3 07-MAY-2014 Page 4 of 12 

Printed in England 
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 

(2) Observe all WARNINGS and CAUTIONS appearing in the AMM 

referred to in this Service Bulletin. 

B.Preparation 

(1) Refer to AMM 12-10-24 and remove all aircraft electrical 

power. 

(2) Arrange appropriate staging/access platforms to allow safe 

inspection of all the rear fuselage aft skin Lap joints. 

(3) Remove dorsal panels 273CT, 275AT, 275BR and 275CR to reveal 

lap joint at stringer 2 right. 

C.Inspection 

(1) Refer to Drawing 1 or Drawing 2, as appropriate, and Appendix 

2. Perform an external eddy current inspection on the rear 

fuselage aft skin lap joints at stringer 11, 18 and 30 left 

and right and stringer 2 right, between frame 39Y and frame 

44. 

NOTE: Inspection aft of frame 44 is not required. 

NOTE: There may be external skin repair plates fitted to the 

aircraft which obscure the areas subject to inspection 

or impede the inspection process. These areas are not to 

be inspected but must be reported to BAE SYSTEMS using the reporting form provided in Appendix 1 of this ISB. 

NOTE: For BAe 146-100, BAe 146-200 and BAe 146-300 aircraft 

with large freight doors, lap joints 11 and 18 left 

forward of frame 43, and lap joint 2 right forward of 

frame 42, are obscured by the Large freight door 

surround skin doublers. These areas are not to be 

inspected (see Drawing 2). 

(2) If cracks, corrosion or any other defects are found, contact 

BAE SYSTEMS for an appropriate repair scheme. 

D.Test 

Not applicable. 

Date: 13-JUN-2012 

Revision: 3 07-MA Y-2014 

Printed in England 

ISB. 53-239 

Page5of12 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

E.Close up 

(1) Make certain work area is clean, and clear of tools and 

miscellaneous equipment. 

(2) Install dorsal panels previously removed for access. 

(3) Remove staging/access platforms previously arranged for 

access. 

F.Documentation 

(1) Complete a copy of the Inspection Report (Appendix 1) 

attached to this ISB and return by fax or mail. 

OR 

Return all required Inspection Report details via e-mail. 

G.Terminating action 

(1) None. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

ISB. 53-239 

Page6of12 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

FRAME 

43 

FRAME I FRAME 

44 39Y 

I I STR2 b-~----~~==========~ 

STR 11 RH -

FRAME 0000 

DODO 

FRAME 

39Y 

I 

~ VIEW LOOKING INBOARD 

LEFT SIDE 

STR 11 RH 

43

1 FRAME 44 

I 

STR 18 RH -

STR 30 RH-

- STR 11 LH 

- STR 18 LH 

- STR30LH 

STR2 

VIEW LOOKING AFT 

0 

VIEW LOOKING INBOARD 

RIGHT SIDE 

--- LAP JOINTS TO BE INSPECTED 

¢Jc 

N5323902 

AREAS OF INSPECTION, LEFT AND RIGHT - PASSENGER AIRCRAFT 

DRAWING 1. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

ISB. 53-239 

Page7of12 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

FRAME FRAME 

43 39Y 

44 42 FRAME I FRAME I 

I STR2RH ~~~P===9=============~ 

FRAME FRAME 

39Y 

I 

431 FRAME 

44 

I ,--------

I--

1--

D '--------' 

0 ~ 

[!] 

VIEW LOOKING INBOARD 

LEFT SIDE 

t--

1--

~ 

--- LAP JOINTS TO BE INSPECTED 

- STR 11 LH 

- STR 18 LH 

0 

VIEW LOOKING INBOARD 

RIGHT SIDE 

STR 2 RH 

VIEW LOOKING AFT 

Qc 

N5323907 

AREAS OF INSPECTION, LEFT AND RIGHT - AIRCRAFT WITH LARGE FREIGHT DOOR 

DRAWING 2. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

ISB. 53-239 

Page8of12 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

3.Material information 

None. 

Date: 13-JUN-2012 ISB. 53-239 Revision: 3 07-MAY-2014 Page9of 12 

Printed in England 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

This Page Is Intentionally Left Blank. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

ISB. 53-239 

Page 10of 12 
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 (Q) 1292 675432 

e-mail raengliaison@baesystems.com 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

ISB. 53-239 

Page 11 of 12 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

This Page Is Intentionally Left Blank. 

Date: 13-JUN-2012 ISB. 53-239 

Revision: 3 07-MAY-2014 Page 12 of 12 

Printed in England 
BAE SYSTEMS (Operations) Limited, Prestwick International Airport, Ayrshire, KA9 2RW, Scotland. 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

TRANSMITTAL FOR INSPECTION SERVICE BULLETIN REVISION 

SERVICE BULLETIN No.ISB. 53-239 APPENDIX 2 

DATE: 13-JUN-2012 

TITLE: EXTERNAL EDDY CURRENT INSPECTION INSTRUCTION FOR THE 

EXAMINATION OF THE REAR FUSELAGE AFT SKIN LAP JOINTS. 

REVISION: 3 DATE: 07-MAY-2014 

ACTIONS 

(1) Remove and discard appendix complete at revision 2. 

(2) Insert appendix complete at revision 3. 

REASON FOR REVISION 

(1) There are no changes to this Inspection Instruction as a 

result of ISB 53-239 revision 3. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

REVISION TRANSMITTAL SHEET 

ISB. 53-239 

Page1of2 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

TRANSMITTAL FOR INSPECTION SERVICE BULLETIN REVISION 

SERVICE BULLETIN No.ISB. 53-239 

This Page Is Intentionally Left Blank. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Pri nted i n England 

REVISION TRANSMITTAL SHEET 

ISB. 53-239 

Page2of2 
BAE SYSTEMS (Operations) Limited, Prestwick International Airport, Ayrshire, 

KA9 2RW, Scotland. 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

APPENDIX 2 

TITLE: EXTERNAL EDDY CURRENT INSPECTION INSTRUCTION FOR THE 

EXAMINATION OF THE REAR FUSELAGE AFT SKIN LAP JOINTS. 

1 .PROCEDURE 

A.GENERAL 

(1) This Low frequency, phase analysis, external eddy current 

inspection instruction has been produced to detect cracks in 

the rear fuselage aft skin Lap joints. 

B.COMPONENT OR AREA TO BE INSPECTED 

(1) The components to be inspected are the rear fuselage aft skin 

Lap joints at stringers 11, 18 and 30 Left and right and 

stringer 2 right, between frame 39Y and frame 44 (see Drawing 1 or Drawing 2, as appropriate). 

C.DESCRIPTION OF POSSIBLE DAMAGE 

(1) Cracks 0.5 in. (12.7 mm.) or greater in Length that Lie 0.016 

in. (0.41 mm.) or Less below the surface of the skin panels 

at the skin Lands. It is anticipated that cracks will 

originate in, and propagate along, the rebate which forms the 

skin Land. 

D.RELATED DOCUMENTS 

(1) NTM Part 1, Chapter 20-00-00, Section 3, Safety Precautions. 

(2) NTM Part 6, Chapter 20-00-00, Eddy Current Testing - General. 

(3) Aircraft Maintenance Manual (AMM). 

(4) Test Instrument Manufacturer's Handbook. 

E.EQUIPMENT AND MATERIALS 

(1) The following equipment was used during the development of 

this inspection instruction and was found acceptable. 

( 1 ) Instrument 

(2) Probe 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Table 1. 

Elotest B1v4 phase analysis eddy current 

instrument, with 81-RS adapter, from Rohmann 

(UK) Ltd. 

Absolute shielded probe with ferrite core, 

300 Hz. - 100 kHz. Part number PKA 42-9E, 

from Rohmann (UK) Ltd (Ref. Drawing 4). 

Printed in England 

ISB. 53-239 

Page1of14 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

(3) 

(4) 

( 5) 

Lead 

Reference Standard 

Straight edge 

APPENDIX 2 

Part number EK-2-HF/1, from Rohmann (UK) Ltd. 

Locally manufactured. 

Part number SORFIT 146/166/1 (Ref. Drawing 

and Drawing 6). 

Locally manufacture from suitable 

non-conductive material such as plastic or 

nylon. 

NOTE: Reference Standard SORFIT, 146/166 may be used for this 

inspection provided SLOT A2 ONLY is used when setting 

sensitivity. Slots A1, B1 and B2 were included for 

development purposes and should not be used for this 

inspection. 

NOTE: Any comparable eddy current equipment may be used 

provided it satisfies the requirements of this 

instruction and is capable of resolving the slot in the 

reference standard at the required Level of sensitivity. 

F.PREPARATION FOR INSPECTION 

(1) Aircraft. 

(a) Ensure adequate staging/access platforms are in place to 

provide safe access to the inspection areas. 

(b) Remove dorsal panels 273CT, 275AT, 275BR and 275CR to 

uncover Lap joint at stringer 2. 

<2> Component. 

(a) Ensure scan surfaces are clean, smooth (flatten sealant if 

protruding) and free from flaking paint. 

(b) Check the inspection areas for any visible damage prior to 

inspection. 

G.INSTRUMENT CALIBRATION 

(1) Instrument settings. 

Initial settings 

Alarm 

Frequency 

Date: 13-JUN-2012 

Revision: 3 07-MA Y-2014 

Table 2. 

Refer to manufacturers instructions. 

Optional - refer to manufacturers instructions. 

Inspection Frequency Set to 10 kHz. 

Printed in England 

ISB. 53-239 

Page2of14 
Gain 

BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

Set to produce required sensitivity. 

Pre-amp 

Y spread 

X spread 

0 dB. 

20 dB. 

0 dB. 

APPENDIX 2 

F i l t e r: Band Set to Static. 

Bandwidth limiter 

Timebase/Display 

Dot position 

High pass 

Low pass 

Set to Off. 

Y/X. 

Reference Drawing 4. 

(2) Sensitivity setting (Ref. Drawing 4). 

Set to Of f. 

Set to 10 Hz. 

(a) Place the probe on the reference standard away from the 

sub-surface slot and balance the instrument. 

(b) Set Lift-off effect to horizontal and to the Left. 

(c) Slide the probe over the sub-surface slot and note the 

response. Adjust the instrument settings to obtain a 

display similar to that shown in Drawing 4. Ensure that the 

slot produces a positive vertical spot displacement of 50 

percent of FSH. 

H.INSPECTION PROCEDURE 

(Ref. Drawing 1 or Drawing 2, as appropriate, and Drawing 3). 

(1) Inspection method. 

(a) Place the probe on the fuselage outer skin centrally over 

the skin Land gap and balance the instrument. 

NOTE: Care should be taken when balancing the instrument. 

The effect of balancing on a defect will cause the 

slot to move more rapidly downwards when the end of 

the crack has been reached. If in doubt, the balance 

can be checked on a different skin Land. 

(b) Adjust Lift-off as required. 

(c) Scan along the skin land gap, using the straight edge to 

keep the probe central and observe all signal responses. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

I SB. 53-239 

Page3of14 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

APPENDIX 2 

(d) Scan the skin along the Lands at the rear fuselage aft skin 

Lap joints at stringers 11, 18 and 30 Left and right and 

stringer 2 right. 

I.ACCEPTANCE CRITERIA 

(1) Interpretation. 

(a) Cracks are indicated by a rapid vertical spot displacement 

away from the balanced position (Ref. Drawing 3). 

NOTE: Cracks and other discrete surface damage are usually 

identified by a rapid positive vertical spot 

displacement away from the balanced position. 

However, once the crack or damage is passed the spot 

returns to the balanced position. 

NOTE: Smooth, gradual spot movement is a common 

occurrence, which happens for a variety of reasons 

such as paint thickness variation (Lift-off), edge 

effect and conductivity changes. 

(2) Accept/Reject criteria. 

(a) Any indication with a rapid vertical spot displacement 

equal to or greater than 20 percent of FSH height that 

cannot be attributed to probe handling, fasteners or 

component geometry shall be considered as a crack. 

(3) Reporting/repair/rectification. 

(a) ALL crack and discontinuity indications are to be recorded 

in the relevant aircraft documentation and the appropriate 

BAE SYSTEMS approved repair/rectification action taken. 

NOTE: The word discontinuity is a generic term for faults 

such as cracks, corrosion and mechanical damage. 

J.REPORTING PROCEDURE 

(1) Report all cracks/discontinuities to:-

Fleet Data Department (Building 37), 

BAE SYSTEMS (Operations) Limited, 

Prestwick International Airport, 

Ayrshire, 

Scotland, 

KA9 2RW. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

ISB. 53-239 

Page4of14 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

APPENDIX 2 

(2) Also send the following information:-

(a) Aircraft constructor's number. 

(b) Aircraft registration. 

(c) Flying hours and number of Landings. 

(d) SSID 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. 

Date: 13-JUN-2012 

Revision: 3 07-MA Y-2014 

Printed i n England 

ISB. 53-239 

Page5of14 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

FRAME 

43 

FRAME FRAME 

44 39Y 

I I 

STR ~-*'==-f======~ 

STR 11 RH -

APPENDIX 2 

FRAME DODD Qc 

DODD 

FRAME 

39Y 

I 

~ VIEW LOOKING INBOARD 

LEFT SIDE 

STR 11 RH 

43

1 FRAME 44 

I 

- STR 11 LH 

- STR 18 LH 

- STR 30 LH 

[f) 

VIEW LOOKING AFT 

0 

VIEW LOOKING INBOARD 

RIGHT SIDE 

--- LAP JOINTS TO BE INSPECTED 

N5323902 

LOCATION OF INSPECTION AREAS, LEFT AND RIGHT - PASSENGER AIRCRAFT 

DRAWING 1. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

ISB. 53-239 

Page6of14 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

APPENDIX 2 

FRAME FRAME 

43 39Y 

44 42 FRAME I FRAME I 

I STR2RH b-~~====~============~ 

FRAME FRAME 

39Y 

I 

43

1 FRAME 44 

I ,-----. 

r---

~ 

0 '----' 

f) 

....... 

~ VIEW LOOKING INBOARD 

LEFT SIDE 

r--

-

~ 

--- LAP JOINTS TO BE INSPECTED 

- STR 11 LH 

- STR 18 LH 

- STR 30 LH 

STR 11 RH ~ 

0 

VIEW LOOKING INBOARD 

RIGHT SIDE 

STR 2 RH 

@] 

VIEW LOOKING AFT 

Qc 

N5323907 

LOCATION OF INSPECTION AREAS, LEFT AND RIGHT - AIRCRAFT WITH LARGE 

FREIGHT DOOR 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

DRAWING 2. 

Printed in England 

ISB. 53-239 

Page7of14 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

EXPECT A SMALL INDICATION DUE TO FASTENERS 

FALLING CLOSE TO THE SKIN LAND GAP 

(THIS IS LIKELY AT CERTAIN FRAME POSITIONS) 

-----------r------------ E~ ------~ STRAIGHT EDGE 

SCAN ALONG THE SKIN 

LAND GAP USING THE 

STRAIGHT EDGE AS A 

PROBE GUIDE 

FUSELAGE 

OUTER SKIN 

TYPICAL 

STRINGER 30 SHOWN 

PROBE POSITIONING AND SCAN DETAILS 

DRAWING 3. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

LAP 

JOINT 

APPENDIX 2 

ETCHED 

REBATE 

SECTION 'E-E' 

N5323903 

ISB. 53-239 

Page8of14 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

APPENDIX 2 

SIGNAL FROM SUB-SURFACE 

SLOT- 50% F.S.H. 

75%FSH r-~~-,---.---.---.---,---,---,--,r/ __ _, 

_____ j _____ _l_ ____ j___ __ _L __________ l_ ___ _l ____ .~_l_ . __ j _____ _ 

50% FSH 

25% FSH 

I I I I I I 1 I I I I I I I I I I I I I I I I I I I I 1 1 I I I I I I I I 

-----+-----t-- ----~-----~ ------ ------:---- --~- --- ~------+--- --- 1 I I I I I t I I I I I I I I I I I I I I I I I 

I I I I I I I I ------:------r -----~ ---- --r----- ----- -~--- --t----- ------t ------ , I I I I I I 

I I I I I I I I I I I I I I I I I I I 1 I 

' ' ' ' ' ' ------:--- ---~---- -- ~---- -~------ ----- ~------~----- --- --~-- ---- 1 I I I I I I I I I I I I 1 1 I I I I I I 1 I 

-----+-----~-- 1 I 

---+-----~----- I 

------~-=H---1-----I-----~------ I I I I I I I I I I I 

' ' ' 

/

t·----+-----t------r-----1----- -----i------r-----1------r------ , I I I I 1 I I 

I I I I I t I I I I I I I 1 I I 

LIFT OFF 1 t 1 t 1 r t t 

PROBE IN 

SUB-SURFACE 

SLOT POSITION 

TYPICAL ELOTEST B1 v4 SCREEN DISPLAY FOR 

SUB-SURFACE SLOT IN REFERENCE STANDARD 

'X' INDICATES 

BALANCE POSITION 

BALANCE POSITION 

I PROBE IN 

~ 

0 

SORFIT 146/166/1 

0.79in (20mm) 1· ·1 

0 

E' 

E 

~ 

~ 

c: 

iij 

<Xl 

0 

-.-----------,----/ ' ' 

SUB-SURFACE 

SLOT 

0 

PKA 

42-9E 

~fl 0.4in (10mm) DIA. 

PROBE FACE 

MANUFACTURER: ROHMANN (UK) LTD 

TYPE: ABSOLUTE FERRITE CORE (SHIELDED) 

PART NUMBER: PKA 42-9E 

FREQUENCY RANGE: 300Hz-100kHz 

CONNECTOR: FISCHER 4 PIN 

INSTRUMENT CALIBRATION AND PROBE DETAILS 

DRAWING 4. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

N5323904 

ISB. 53-239 

Page9of14 
' BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

4.0in CF I (1 01 .6mm) 1 

---------

- I 

0.068in 

(2

1

5

.

.

00in 

4mm) J-------------t---------~ G I 

'==========l I 

(1.7.mm) 

0.432in 

G 

(10.97mm) ' 

. -f----~-I------~·.~-!-----8

(12.7mm) 

0.50on 

1 I 1 

1 -f-----1---- G)- --~- -@ I 

0.50in 1 1 1 I o 

(

12

.?mm) SORFIT 1146/166/1 I I b I 

1.. ..1.. ..\.. .. j.. !\.. .. \.. ..1 

0.50in 0.75in " 0 .50in 

(12.7mm) (19 .05mm) (12.7mm) 

PITCH 

f -----]---{------- j--- {- -------}--{-------}---t-------j---{-----j 

SECTION 'G-G' 

1. 1NNERSKIN 2. OUTER SKIN 3. FASTENERS 

BS L 166 BS L 166 

0.126in (3.2mm) 0.058in (1 .47mm) 

MACHINED 

RIVET 

EQUIVALENT MATERIAL SPECIFICATION 4070-40-10 

INTERNATIONAL DESIGNATION 5 POSITIONS 

2014A-T4 

I 

2014A-T4 

ALCLAD ALCLAD 

2.50in 

(63.5mm) 

APPENDIX 2 

2 

SECTION 'F-F' 

FOR FASTENER INFORMATION AND IDENTIFICATION REFER TO STRUCTURAL REPAIR MANUAL 51-41-00. 

FOR DRILLING AND COUNTERSINKING INFORMATION REFER TO STRUCTURAL REPAIR MANUAL 51-42-00. 

UNLESS STATED OTHERWISE DIMENSIONAL TOLERANCE IS +/- 0.010in . (0.25mm). 

THE APPLICATION OF SURFACE PROTECTION IS OPTIONAL. 

THE REFERENCE STANDARD DOES NOT REQUIRE ANY JOINTING COMPOUNDS. 

MARK REFERENCE NUMBER ON TOP SURFACE IN A PERMANENT MANNER. 

N5323905 

CALIBRATION STANDARD PART NUMBER SORFIT 146/166/1 - MATERIAL DETAILS 

DRAWING 5. 

Date: 13-JUN-2012 

Revision: 3 07-MA Y-2014 

Printed in England 

ISB. 53-239 

Page 10of 14 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

1 .. 

1.75in 

(44.45mm) 

0.50in 

(12 .7mm) 

... 1.. ...1 .. 

I I I I 

I I I I 

1.75in 

(44.45mm) 

H¢ 1------J -'~;;;;;;..t~::.=------------1 

0 0 0 

0 0 

_l 0.068in 

0.058in 0.068in 

--t (1.73mm) 

(1.47mm) (1.73mm) 

RAD SLOT 

[BJ QJ 

APPENDIX 2 

SLOT 

/2 

0 0 0 

0 0 

SORFIT 146/166/1 

ONE SLOT IN ITEM 1 = 0.5in (12.7mm) LONG 

SLOT IS SUB-SURFACE 

MAXIMUM SLOT WIDTH 0.010in (0.25mm) 

NO SLOTS IN ITEM 2 

DIMENSIONAL TOLERANCE +/-0.010in (0.25mm) 

N5323906 

CALIBRATION STANDARD PART NUMBER SORFIT 146/166/1 - SLOT DETAILS 

DRAWING 6. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

ISB. 53-239 

Page 11 of 14 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

2.ACCOMPLISHMENT INSTRUCTIONS 

Not applicable. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

APPENDIX 2 

ISB. 53-239 

Page 12 of 14 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

3.MATERIAL INFORMATION 

Not applicable. 

Date: 13-JUN-2012 

Revision: 3 07-MAY-2014 

Printed in England 

APPENDIX 2 

ISB. 53-239 

Page13of14 
BAE SYSTEMS 

INSPECTION SERVICE BULLETIN 

BAe 146 SERIES/AVRO 146-RJ SERIES AIRCRAFT 

This Page Is Intentionally Left Blank. 

Date: 13-JUN-2012 ISB. 53-239 

Revision: 3 07-MAY-2014 Page 14 of 14 

Printed in England