## Service Bulletin

F okker 70/100

Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Revision

- - - - - - - - - - - - - - - - -

Page 18 19 20 21 22 23 24 25 26 27

Revision

- - - - - - - - - -

Jun 16 /11 SBF100

- 53

- 115 Page 1

Copyright All righ ts reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its custome rs on a confidential basis subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof, or the use of any information contained therein for purposes other than explicitly allowed by the afores aid agreement, is not permitted except with the prior written permission of Fokker Services B.V. FUSELAGE

Forward Fuselage

- The R epetitive External I nspection and Temporary Repair of the B utt J oint s

at S tringer s 12 and 61 between S ta tions 38 5 0 and 5305.

1. Planning Information

A. Effectivity

(1) F28 Mark 0070/0100 aircraft serial numbers:

11268 thru 11283

, 11286, 11289, 11291, 11293, 11295, 11300, 11303, 11306,
11308, 11310, 11312 thru 11314, 11316, 11318, 11321, 11323 thru 11335, 11337,
11338, 11340, 11345, 11346, 11349, 11352 thru 11361, 11365 thru 11370, 11372,
11373, 11376 thru 11380, 11387, 11388, 11391

, 11392, 11395 thru 11399

, 11403 thru 1140 8

, 11411 thru 11419

, 11425 thru 11428

, 11432

, 11435

, 11436

, 11438

, 11439

, 11444 thru 11450

, 11456 thru 11460

, 11464 thru 11469

, 11475 thru 11479

, 11481 thru 11506

, 11509

, 11511 and 11513 thru 115 85

.

B. Concurrent Re quirements

(1) Not applicable.

C. Reason

(1) A crack was reported at a butt joint on the forward fuselage underneath the passenger door. Investigation revealed that

, depending on the configuration of the

aircraft

, one or two but t joints in the forward fuselage are cr itical and a repetitive inspection is required.

(2) When crack indications are found the applicable butt joint has to be repaired before further flight.

## Service Bulletin

Fokker 70/100

SBF100

- 53

- 115 Jun 16/11 Page 2

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential b asis subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof, o r the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. D. Description

(1) This S ervice B ulletin is divided in 4 P arts as follows:

P art 1 : The M anufacturing of the Cali bration Plate for the I nspection.

This Part tells how to:

- Manufacture the calibration plate for the inspection according P arts 1 and 2.

P art 2 : The R epetitive External I nspection of the B utt J oint at S tringer 1 2 between

S ta tions 3850 and 5305 (Applicable to F28 Mark 0100 Aircraft Serial
Numbers 11268 thru 11283, 11286, 11289, 11291, 11293, 11295, 11300,
11303, 11306, 11308, 11310, 11312 thru 11314, 11316, 11318, 11321,
11323 thru 11335, 11337, 11338, 11340, 11345, 11346, 11349,
11352 thru 11361, 11365 t hru 11370, 11372, 11373, 11376 thru 11380,
11387, 11388, 11391, 11392, 11395 thru 11399, 11403 thru 11408, 11411
thru 11417, 11419, 11425 thru 11428, 11432, 11435, 11436, 11438, 11439,
11444 thru 11450, 11456 thru 11460, 11464 thru 11469, 11475 thru 11479

, 11481 thru 11487, 11490 thru 11495, 11498, 11499, 11501, 11502, 11504, 11506, 11513 thru 11515, 11519, 11520, 11522 and 11523)

.

NOTE : This Part is not applicable to aircraft s erial n umber 11418, because this aircraft has already been permanently repaired /modified (similar to the terminating repair

/modification according SBF100

- 53

- 116).

This Part tells how to:

- Carry out the external inspection of the butt joint at stringer 12, below the forward opening passenger door, using Low Frequency Eddy Current (LF EC).

P art 3 : The R epetitive External I nspection of the B utt J oint at S tringer 61 between

S ta tions 3850 and 5305 (Applicable to all aircraft listed in the paragraph 1.A. Effectivity)

.

This Part tells how to:

- Carry out the external inspection of the butt j oint at stringer 61, below the forward service/emergency door, using Low Frequency Eddy Current (LFEC).

P art 4 : The T emporary R epair of the B utt J oint ( s )

.

This Part tells how to:

- Install a temporary repair when crack indications are found

.

E. Compliance

(1) Fok ker Services recommends the accomplishment of Part 2 and 3 of this Service Bulletin at the following times:

T he first inspection has to be carried out before the aircraft exceeds a total number of

20 000 flight cycles (FC) or within 180 flight cycles (FC) after the date of issue of this

Service Bulletin

, whichever comes later. T he inspections must be repeated at intervals not exceeding 1 000 flight cycles (FC)

.

## Service Bulletin

Fokker 70/100

Jun 16/11 SBF100

- 53

- 115 Page 3

Copyr ight All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basis subject to the provisions of an agreement. Reproduction or disclosure to third parties of t his document or any part thereof, or the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V.

NOTE 1 : An alternative inspection method is a visual Detailed I nspection of the butt

joint(s) f rom the inside. Only note that to gain access to the inspection area from the inside several components must be removed and after the inspection has been performed all components that are removed must be

reinstalled and tested , all in accordance with the a pplicable AMM procedures.

NOTE 2 : It is expected that EASA will issue an Airworthiness Directive (AD) with

respect to this subject with the same compliance terms. Refer to the EASA website for the publication of the Airworthiness Directive.

NOTE 3 : As a p recautionary measure the temporary repair can be performed on

each frame bay

, even without crack findings. The se temporary repair s will

in the end ha ve to be replaced by a terminating repair /modification (SBF100

- 53

- 116)

. The c urrent expectation is that the temporary repair s
ha ve to be replaced within 10 000 flight cycles (FC)

. However final actions

as mentioned in NOTE 4 may require an earlier replacement. When the temporary repair has been performed on one or more frame bays

, these frame bays no longer req uire the repetitive inspection.

NOTE 4 : This Service Bulletin covers the interim actions required to assure

continued airworthiness. Final action (superseding and cancelling this SB)

will likely be covered by a task in the ALI

- section (report SE

- 623) of th e Maintenance Review Board ( MRB ) document and a terminating repair/ modifica tion as mentioned under NOTE 3

.

F. Approval

(1) The technical content of this document is approved under the authority of DOA nr.

EASA.21J.059.

G. Manpower

(1) Approximately 2 ma n

- hours are neces sary to manufacture the special inspection

calibration tool according P art 1 of this Service Bulletin.

This table of manpower will help you to schedule and do this Part :

Instructions Men Man

- hours Elapsed time (hours) Manufacturing 1 2,0 2,0

Total 2,0 2,0

NOTE : This estimate does not include the time necessary for the sealant to cure.

## Service Bulletin

Fokker 70/100

SBF100

- 53

- 115 Jun 16/11 Page 4

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential b asis subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof, o r the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. (2) Approximately 1 man

- hour i s necessary to do Part 2 of this Service Bulletin on one

aircraft.

This table of manpower will help you to schedule and do this Part :

Instr uctions Men Man

- hours Elapsed time (hours)

Removal

- - - Modification Inspection 1 1,0 1,0

Installation

- - - Testing

- - - Total 1,0 1,0

(3) Approximately 1 man

- hour is necessary to do Part 3 of this Service Bulletin on one

aircraft.

This table of ma npower will help you to schedule and do this Part :

Instructions Men Man

- hours Elapsed time (hours)

Removal

- - - Modification Inspection 1 1,0 1,0

Installation

- - - Testing

- - - Total 1,0 1,0

(4) Approximately 40 man

- hours are necessary to do Part 4 of this Service Bulletin on

one aircraft.

This table of manpower will help you to schedule and do this Part :

Instructions Men Man

- hours Elapsed time (hours)

Removal

- - - Modification Inspection 2 40 ,0 20 ,0

Installation

- - - Testing

- - - Total 40 ,0 20 ,0

NOTE 1 : This estimate is based on the temporary repair of all eight frame bay s . If only

one frame bay is repaired approximately 4

- 6 man

- hours are necessary.

NOTE 2 : This estimate does not include the time necessary for the paint to dry and/or

th e sealant to cure.

(5) The estimated hours are for direct labor done by experienced personnel. They are calculated based on the conditions given in SBF100

- 00

- 001 (Service Bulletin Introduction, section 2.C., "Manpower").

## Service Bulletin

Fokker 70/100

Jun 16/11 SBF100

- 53

- 115 Page 5

Copyr ight All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basis subject to the provisions of an agreement. Reproduction or disclosure to third parties of t his document or any part thereof, or the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. H. Weight and Balance

(1) Part 4 :

(a) Repair acco mplished on one side between sta 3850

- 417 5 :

1 Weight change: + 0

, 08 kg ( 0

. 177 lb) Index change: Mark 0100:

- 0

. 011

Mark 0070:

- 0.009

.

(b) Repair accomplished on one side between sta 417 5

- 4610:

1 Weight change: + 0

, 15 kg ( 0

. 324 lb) Index change: Mark 0100:

- 0.0 19

Mark 0070:

- 0.015.

(c) Repair accomplished on one side between sta 4610

- 4850:

1 Weight change: + 0

, 07 kg ( 0

. 149 lb) Index change: Mark 0100:

- 0.008

Mark 0070:

- 0.007.

(d) Repair accomplished on one side between sta 4850

- 5305:

1 Weight change: + 0

, 14 kg ( 0

. 305 lb) Index change: Mark 0100:

- 0.017

Mark 0070:

- 0.014.

I. Electrical Load Data

(1) Not changed.

J. Software Accomplishment Summ a ry

(1) Not applicable.

K. References

(1) Fokker 70/100 Structural Repair Manual (SRM)

Fokker 70/100 Aircraft Maintenance Manual ( AMM )

Fokker 70/1 00 Maintenance Review Board (MRB) document Fokker 70/100 Maintenance Planning Document (MPD)

Fokker 70/100 Service Bulletin:

- SBF100

- 53

- 116

Fokker Consumable Material List (CML)

Fokker int ernal reference(s):

- ECR015780

.

## Service Bulletin

Fokker 70/100

SBF100

- 53

- 115 Jun 16/11 Page 6

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential b asis subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof, o r the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. L. Publications Affected

(1) This SB affects the publications listed below:

(a) Maintenance Documentation

Not affected.

(b) Maintenance Programs

- Fokker 70/100 Maintenance Review Board (MRB)

- Fokker 70/100 Maintenance Planning Document (MPD)

(c) Special Instructions for Continued Airworthiness (IC A)

The effect of this Service Bulletin on the special ICA is as follows:

YES NO

- Electrical Wiring Interconnection System (EWIS)

- X

- Fuel Tank Safety (FTS)

- X

- Damage Tolerance of Fatigue Critical Structure X

-

NOTE : If “YES”, when not already incorporated, the changed ICA will be incorporated in the MRB document within one calendar year from the date of issue of this Service Bulletin. Until then, no actions are required.

(d) Operational Documentation

Not affect ed.

(2) Report to Fokker Services that t his SB has been carried out on the applicable aircraft. Send to Fokker Services the “Reporting Quality Form” of this S B. Refer to the last page of this SB

.

(3) For incorporation of this Service Bulletin in your documentation refer to

SBF100

- 00

- 001 (Service Bul letin Introduction, section 4 "Incorporation of Service Bulletins in Documentation of Fokker Services").

M. Interchangeability or Intermixability of Parts

(1) Not applicable.

## Service Bulletin

Fokker 70/100

Jun 16/11 SBF100

- 53

- 115 Page 7

Copyr ight All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basis subject to the provisions of an agreement. Reproduction or disclosure to third parties of t his document or any part thereof, or the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. 2. Material Information

A. Material

– Price and Availability

(1) The materials are local source items.

B. Material Required

(1) These parts, which are necessary to complete P art 1 and/or P art 4 of this Service Bulletin on 1 aircraft, are not part of the mod kit.

New Part Number Qty Keyword Info Old Part Instructions/

* 1 * 2 Number Disposition

Alodine 1 201

- AR* Coating Fk13

- 003D **

- Local source

F0N1

- 4311

- 1 AP

- * 3 AR* AR* Sheet, aluminum 2024T3 Alclad

- Local source

F0N1

- 4311

- 2 AD

- * 4 AR*

- Sheet, aluminum 2024T3 Alclad

- Local source

F0N2

- 6395B 5 xx

- AR* CSK blind rivet CR3222

- 5

- x x

- Local source

F0N2

- 639 7 B 6 xx

- AR* CSK blind rivet CR322 4

- 6

- x x

- Local source

F0N18

- 9151S0 5

- AR* CSK repair washer

- - Local source

F0N18

- 9151S06

- AR* CSK repair washer

- - Local source

PR1436GA1

- 2 AR* AR* Sealant Fk09

- 01 6 **

- Local source

PR1436G B1

- 2

- AR* Sealant Fk0 9

- 01 7 **

- Local source

S15

- 60CRME52700

- AR* Aerodur Primer Fk07

- 008**

- Local source

NOTES : * Use as much as necessary

** Refer to the CML for material numbers

* 1 Applicable to Part 1

* 2 Applicable to Part 4

* 3 1,6 mm (0.063 inch) 2024T3 Alclad aluminum sheet

* 4 2,0 mm (0.080 inch) 2024T3 Alclad aluminum sheet

.

(2) These mod kit parts are necessary to do this Service Bulletin on 1 aircraft.

(a) Not applicable.

## Service Bulletin

Fokker 70/100

SBF100

- 53

- 115 Jun 16/11 Page 8

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential b asis subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof, o r the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. C. Tooling

– Price and Availability

(1) The following special tools are required to accomplish Part 2 and 3 of this Service

Bulletin:

Part Number Specification Reference Supplier

ELOTEST

- B1SB Phase analysis EC tester S0137* Rohmann

SPT4039 Sliding probe, reflection
type, 1

- 100 kHz - Servicing Europe

NDT

CR

- RE

- TF180 Interconnecting cable

- Servicing Europe

N DT

SB10053115PLATE Calibration plate

- Local source**

NOTE S : * Reference number when ordering at Fokker services BV.

** Calibration plate pn SB10053115 PLATE has to be manufactured in

accordance with Part 1 of this Service Bulletin.

D. Drawings Required

(1) Not applicable.

## Service Bulletin

Fokker 70/100

Jun 16/11 SBF100

- 53

- 115 Page 9

Copyr ight All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basis subject to the provisions of an agreement. Reproduction or disclosure to third parties of t his document or any part thereof, or the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. 3. Accomplishment Instructions

General :

- For CML material number references, refer to “Myfokkerfleet.com/Documentation/CML” or
AMM task 20

- 30

- 00

- 910

- xxx

- A (Consumable Material List)

.

- For Standards and Process Manual (SPM) references, refer to

“ Myfokkerfleet.com/Documentation/SPM”.

- For the application of Alodine 1201 (Fk13

- 003D), refer to the AMM, chapter 51

- 22

- 00.

- For the application of primer and paint, refer to the AMM, chapter 51

- 21

- 00.

- For the applicati on of s eal ant PR1436G A1

- 2 (Fk09

- 0 1 6 ) and PR1436G

- B 1

- 2 (Fk09

- 017) refer to the AMM, chapter 51

- 23

- 00.

- For the removal/installation of solid rivets, refer to the SRM, chapter 51

- 40

- 02.

- For the installation of blind rivets, refer to the SRM chapters 51

- 40

- 03, 51

- 40

- 04

and 51

- 40

- 05.

- For drilling and dimpling procedures, refer to the SRM, chapter 51

- 21

- 02.

- For drilling and countersinking procedures, refer to the SRM, chapter 51

- 22

- 01.

WARNING : BE CAREFUL WHEN YOU USE THE CONSUMABLE MATERIALS. OBEY

THE INSTRUCTIONS AND MANUFACTURER'S HEA LTH AND SAFETY

INSTRUCTIONS.

Part 1 : The M anufacturing of the Calibration Plate for the Inspection

Refer to figure 1.

A. Manufacturing of the calibration plate

.

(1) Manufacture 2 plate s A in accordance with figure 1 “Plate A”. Use:

- AR Sheet, aluminum pn F0N1

- 4311

- 2AD

- *

NOTE : * 2,0 mm (0.080 inch) thick 2024T3 Alclad aluminium sheet.

(2) Manufacture 1 x plate B in accordance with figure 1 “Plate B”. Use:

- AR Sheet, aluminum pn F0N1

- 4311

- 1AP

- *

NOTE : * 1,6 mm (0.063 inch) thick 2024T3 Alclad aluminium sheet.

(a) Make a small hole with a Ø 1

, 0 mm drill in plate B on the indicated position.

(b) Make a 10 mm long saw cut of 0,2 (± 0,1) mm wide with a jigsaw.

B. Assembly of the special tool.

(1) Assemble the special tool in accordance with figure 1 and use the plates

manufacture d in step A.(1) and A.(2). Use:

- AR S ealant , interfaying PR1436G A1

- 2 * Fk09

- 016

NOTE : * Or equivalent

## Service Bulletin

Fokker 70/100

SBF100

- 53

- 115 Jun 16/11 Page 10

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential b asis subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof, o r the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. C. Identification.

(1) Identify the special tool with pn SB1005 3115 PLATE . E ngrave the part number or use a permanent marker.

## Service Bulletin

Fokker 70/100

Jun 16/11 SBF100

- 53

- 115 Page 11

Copyr ight All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basis subject to the provisions of an agreement. Reproduction or disclosure to third parties of t his document or any part thereof, or the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. Part 2 : The R epetitive Extern al I nspection of the B utt J oint at S tringer 12 between S tation s

385 0 and 5305 (a pplicable to F28 Mk 0100 Aircraft Serial Numbers 11268 thru

1128 3 , 11286, 11289, 11291, 11293, 11295, 11300, 11303, 11306, 11308, 11310,

11312 thru 11314, 11316, 11318, 11321, 11323 thru 11335, 11337, 11338, 11340,
11345, 11346, 11349, 11352 thru 11361, 11365 thru 11370, 11372, 11373, 11376
thru 11380, 11387, 11388, 11391, 11392, 11395 thru 11399, 11403 thru 1140 8

, 11411 thru 1141 7, 11419 , 11425 thru 11428, 11432, 11435, 11436, 11438, 11439,
11444 thru 11450, 11456 thru 11460, 11464 thru 11469, 11475 thru 11479, 11481
thru 11487, 11490 thru 11495, 11498, 11499, 11501, 11502, 11504, 11506, 11513
thru 11515, 11519, 11520, 11522 and 11523 )

.

NOTE 1: This part is not applicable to a ircraft serial number 11418, because this aircraft has

already been permanently repaired /modified (similar to the terminating repair /modification according SBF100

- 53

- 116 ).

NOTE 2 : This procedure describes the external L ow F requency E ddy C urrent (LFE C) sliding

probe inspection of the longitudinal butt joint at stringer 12 between frames 3850

and 5305 below the forward opening passenger door

.

A. Preparation of the of the inspection area.

Refer to figure 5

.

(1) Clean the area to be inspected from any dirt with a lint

- free cloth moistened with cleaning agent.

(2) Remove chipped and/or excessive paint

. R efer to NDT M, P art 1 , chapter 51

- 00

- 06.

B. The following special tools are required for the LFEC sliding probe inspection :

Part Number Specification Reference Supplier

ELOTEST

- B1SB Phase analysis EC tester S0137* Rohmann

SPT4039 Sliding probe, reflection
type, 1

- 100 kHz - Servicing Europe NDT

CR

- RE

- TF180 Interconnecting cable

- Servicing Europe NDT

SB10053115PLATE Calibration plate

- Local source**

NOTES : * Referen ce number when ordering at Fokker services BV.

** Calibration plate pn SB10053115PLATE has to be manufactured in

accordance with Part 1 of this Service Bulletin.

## Service Bulletin

Fokker 70/100

SBF100

- 53

- 115 Jun 16/11 Page 12

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential b asis subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof, o r the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. C. Calibration of the measuring equipment.

Refer to figure s 2 and 4

.

INSTRUMENT SETTINGS

(a) Y

/X or Y/time base Y/X

(b) Frequency (kHz) 3.0

(c) Axis spread Y/X (dB) 0/0

(d) Bandwidth MF

(e) Preamplifier (dB) 6

(f) Gain (dB) As required

(g) Phase (degrees) As required

(h) Filter (Hz) LP: 50

(i) Gate ON

(j) Alarm OFF

Initial instrument sett ings

Table 1

(1) Adjust the instrument according to table 1 . S et the balance point at 25% Full Screen Height (FSH) and set the gate to 50 % FSH as indicated in figure 4A.

(2) Position a non

- conductive ruler in such a way that a straight scan can be made with

the ce nter mark of the probe along one skin edge of the butt joint

. R efer figure 2.

NOTE : Centering halfway the splice may cause a non

- relevant lift

- off signal.

(3) Balance the instrument and adjust Phase to get a horizontal lift

- off signature as shown in figure 4B

.

(4) Scan from position I to position II until the maximum crack signal is obtained. Adjust Gain until the crack signal is 75 % FSH . R efer figure 4B.

NOTE : Scan from position I to position II to familiarize with the signature from the

saw

- cut. A real crack ma y increase gradually and exceed 75 % FSH.

D. Inspection of the butt joint.

Refer to figures 3 , 4 and 5

.

(1) Switch the alarm to ON. I nspect the area between the frames using a non

- conductive

ruler . F or the inspection area r efer to figure 5

.

(2) Position the probe at a skin corner along one skin edge of the butt joint and balance

the instrument . R efer figure 3.

(3) Perform a scan along each skin edge ( r efer figure 3 ) and monitor the signal.

## Service Bulletin

Fokker 70/100

Jun 16/11 SBF100

- 53

- 115 Page 13

Copyr ight All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basis subject to the provisions of an agreement. Reproduction or disclosure to third parties of t his document or any part thereof, or the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V.

NOTE : A misalignment of the ruler will decrease the detect ability of cracks and

ca use deviating signatures

.

(4) Mark every position where the signal passes the 50% FSH gate and looks like the slot signals given in figure 4B

.

(5) If no indications above 50% FSH are measured continue with step F.

E. Verification of i nspection results

.

(1) Check the sens itivity setting on the calibration plate. Balance the probe on the aircraft at an opposite skin corner or at a frame position without rivets in the inspection area

and rescan the marked area(s).

NOTE : Adjacent to a through crack an indication may increase gradually and exceed 75% FSH, unlike the saw

- cut in the calibration plate.

(2) If a crack indication of 50 % FSH or more is found, write down the location, orientation and the length of the crack.

F. After inspection procedure

.

(1) If a n indication of 50 % FSH or more is found repair the applicable frame bay(s) in

accordance with P art 4 of this Service B ulletin. If a crack indication of less than 50 %

FSH has been found continue with step F.

Refer to figure 10

.

(2) Fill out the enclosed Reporting Form of figure 10 . Send the filled out reporting form

back to Fokker Services BV. For the address refer to SBF100

- 00

- 001 (Service Bulletin Introduction).

NOTE : This feed

- back is essential for further determination of subsequent actions.

G. Job close up

(1) If necessary restore the aircraft paint scheme. Refer to the Aircraft Maintenance Manual (AMM), chapter 51

- 21

- 00.

(2) Remove all tools and materials from the work area and make sure the area is clean.

## Service Bulletin

Fokker 70/100

SBF100

- 53

- 115 Jun 16/11 Page 14

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential b asis subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof, o r the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. Part 3 : The R epetitive External I nspection of the B utt J oint at S tringer 61 between S tatio n s
3850 and 5305 (Applicable to all aircraft listed in the paragraph 1.A. Effectivity)

.

NOTE : This procedure describes the external Low Frequency Eddy Current (LFEC) sliding probe inspection of the longitudinal butt joint at stringer 61 between frames 385 0 and

5305 below the forward service/emergency door

.

A. Preparation of the of the inspection area.

Refer to figure 6

.

(1) Clean the area to be inspected from any dirt with a lint

- free cloth moistened with cleaning agent.

(2) Remove chipped and/or excessive paint. R ef er to NDT M, P art 1

, chapter 51

- 00

- 06.

B. The following special tools are required for the LFEC sliding probe inspection :

Part Number Specification Reference Supplier

ELOTEST

- B1SB Phase analysis EC tester S0137* Rohmann

SPT4039 Sliding probe, reflection
ty pe, 1

- 100 kHz - Servicing Europe NDT

CR

- RE

- TF180 Interconnecting cable

- Servicing Europe NDT

SB10053115PLATE Calibration plate

- Local source**

NOTES : * Reference number when ordering at Fokker services BV.

** Calibration plate pn SB10053115PLATE has to be manufactured in

accordance with Part 1 of this Service Bulletin.

C. Calibration of the measuring equipment.

Refer to figures 2 and 4.

INSTRUMENT SETTINGS

(a) Y/X or Y/time base Y/X

(b) Frequency (kHz) 3.0

(c) Axis spread Y/X (dB) 0/0

(d) Bandwidth M F

(e) Preamplifier (dB) 6

(f) Gain (dB) As required

(g) Phase (degrees) As required

(h) Filter (Hz) LP: 50

(i) Gate ON

(j) Alarm OFF

Initial instrument settings

Table 1

## Service Bulletin

Fokker 70/100

Jun 16/11 SBF100

- 53

- 115 Page 15

Copyr ight All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basis subject to the provisions of an agreement. Reproduction or disclosure to third parties of t his document or any part thereof, or the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. (1) Adjust the instrument according to table 1. Set the balance point at 25% Full Sc reen Height (FSH) and set the gate to 50% FSH as indicated in figure 4A.

(2) Position a non

- conductive ruler in such a way that a straight scan can be made with the center mark of the probe along one skin edge of the butt joint. Refer figure 2.

NOTE : Centerin g halfway the splice may cause a non

- relevant lift

- off signal.

(3) Balance the instrument and adjust Phase to get a horizontal lift

- off signature as shown in figure 4B.

(4) Scan from position I to position II until the maximum crack signal is obtained. Adjust

Gain until the crack signal is 75% FSH. Refer figure 4B.

NOTE : Scan from position I to position II to familiarize with the signature from the

saw

- cut. A real crack may increase gradually and exceed 75% FSH.

D. Inspection of the butt joint.

Refer to figures 3, 4 and 6

.

(1) Switch the alarm to ON. Inspect the area between the frames using a non

- conductive ruler. For the inspection area r efer to figure 6

.

(2) Position the probe at a skin corner along one skin edge of the butt joint and balance the instrument. Refer figure 3

.

(3) Perform a scan along each skin edge (refer figure 3) and monitor the signal.

NOTE : A misalignment of the ruler will decrease the detectability of cracks and cause deviating signatures.

(4) Mark every position where the signal passes the 50% FSH gate and lo oks like the slot signals given in figure 4B.

(5) If no indications above 50% FSH are measured continue with step F.

E. Verification of inspection results.

(1) Check the sensitivity setting on the calibration plate. Balance the probe on the aircraft at an opposite sk in corner or at a frame position without rivets in the inspection area and rescan the marked area(s).

NOTE : Adjacent to a through crack an indication may increase gradually and exceed 75% FSH, unlike the saw

- cut in the calibration plate.

(2) If a crack indica tion of 50% FSH or more is found, write down the location, orientation and the length of the crack.

## Service Bulletin

Fokker 70/100

SBF100

- 53

- 115 Jun 16/11 Page 16

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential b asis subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof, o r the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. F. After inspection procedure

.

(1) If a n indication of 50% FSH or more is found repair the applicable frame bay(s) in

accordance with Part 4 of this Service Bull etin. If a crack indication of less than 50% FSH has been found continue with step F.

Refer to figure 10

.

(2) Fill out the enclosed Reporting Form of figure 10 . Send the filled out reporting form

back to Fokker Services BV. For the address refer to SBF100

- 00

- 0 01 (Service Bulletin Introduction).

NOTE : This feed

- back is essential for further determination of subsequent actions.

G. Job close up

(1) If necessary restore the aircraft paint scheme. Refer to the Aircraft Maintenance Manual (AMM), chapter 51

- 21

- 00.

(2) Remove all tools and materials from the work area and make sure the area is clean.

## Service Bulletin

Fokker 70/100

Jun 16/11 SBF100

- 53

- 115 Page 17

Copyr ight All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basis subject to the provisions of an agreement. Reproduction or disclosure to third parties of t his document or any part thereof, or the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. Part 4 : The T emporary R epair of the B utt J oint(s )

Refer to figure s 7 , 8 and 9

.

A. Repair the frame bays w here the cracks are found or all frame bays as a precautionary

measure as foll ows:

(1) Remove the fasteners in the applicable frame bay. Leave the fasteners at the frames

installed.

NOTE : When cracks are found on each side of a frame

, repair the frame bay forward

and aft of the frame . D o not install the repair patch over the frame.

B. Man ufacture a repair p atches

.

(1) Manufacture repair p atches that extend from frame to frame in accordance with figure s 7 and 8 . Use :

- AR Sheet, aluminum pn F0N1

- 4311

- 1 AP

- *

NOTE : * 1,6 mm (0.063 inch) thick 2024T3 Alclad aluminum sheet.

(2) Temporary install the repair p atches and copy drill the existing attachment in holes into the repair p atches

.

(3) Deburr all holes and protect all bare aluminum with Alodine and primer. Use:

- AR Coating pn Alodine 1201 Fk13

- 003D

- AR Primer pn S15

- 60CRME52700 Fk07

- 008

C. Install at ion of the repair plate(s)

.

(1) Install all repair parts with blind rivets , repair washers (refer to SRM 51

- 43

- 04) and interfaying sealant and aerodynamically seal the edges of the repair patches . Use :

- AR S ealant pn PR1436GA1

- 2 Fk09

- 016

- AR S ealant pn PR1 436GB1

- 2 Fk09

- 01 7

- AR CSK blind rivets pn F0N2

- 6395B 5xx

- AR CSK blind rivets pn F0N2

- 639 7 B 6 xx *

- AR CSK repair washers pn F0N18

- 9151S0 5

- AR CSK repair washers pn F0N18

- 9151S0 6 *

NOTE : * In the stringer connection angles at stations 3850 and 5 305 in

- 6 rivets are installed. These rivets have to be replaced by reduced countersunk head

blind rivets with pn F0N2

- 6397B6xx (CR3224

- 6

- xx).

(2) Restore the original paint scheme according to AMM 51

- 21

- 00.

D. Job clos e up.

(1) Remove all tools, materials and equipm ent from the working area. Make sure that the working area is clean.

NOTE : If the temporary repair has been performed record in the aircraft documentation the ECR (ECR015780) as well as when and which frame bay(s) have been repaired, for easy determination of applicability of future actions.

## Service Bulletin

Fokker 70/100

SBF100

- 53

- 115 Jun 16/11 Page 18

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential b asis subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof, o r the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. Pos. Descr iption t Dimensions Material Remarks

A Sheet 2,0 200 x 49 2024T3 Alclad 2x

B Sheet 1,6 200 x 80 2024T3 Alclad

- C Sealant 0,2

- PR1436 GA1

- 2 or equivalent

D Crack

- 10,0 x 0

, 2 ±0,1 Saw cut Pre drill Ø 1

, 0 mm

E Tool n o

. - - Engrave /mark SB10053115 PLATE

All dimensions in mm

T he Manufacturing of the Calibration Plate (Part 1).

Figure 1 A

B

A C 4 4

10

200 49

2

, 0 100 80 E

Ø 1 ,0 S B10053115PLATE

D

## Service Bulletin

Fokker 70/100

Jun 16/11 SBF100

- 53

- 115 Page 19

Copyr ight All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basis subject to the provisions of an agreement. Reproduction or disclosure to third parties of t his document or any part thereof, or the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. Slot pos i tion on Calibration Plate

. Figure 2

Typical Scan Pattern on the Butt Joint (Parts 2 and 3)

. Figure 3 I II I SB10053115PLATE

PROBE

S can pattern T ypical crack in butt strap P robe starting point F rame

Non

- conductive

ruler

## Service Bulletin

Fokker 70/100

SBF100

- 53

- 115 Jun 16/11 Page 20

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential b asis subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof, o r the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. Screen Indications (Parts 1, 2 and 3)

. Figure 4 

## B

A

Crack indication

Lift

- off indication

## Service Bulletin

Fokker 70/100

Jun 16/11 SBF100

- 53

- 115 Page 21

Copyr ight All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basis subject to the provisions of an agreement. Reproduction or disclosure to third parties of t his document or any part thereof, or the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. The Inspection Area of the Butt Joint at Stringer 12 between Station s 3850 and 5305

below the Forward Opening Passenger Door (Part 2). Figure 5 Inspection area Forwar d opening

passenger
door

Stgr 12

## Service Bulletin

Fokker 70/100

SBF100

- 53

- 115 Jun 16/11 Page 22

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential b asis subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof, o r the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. The Inspection Area of the Butt Joint at Stringer 61 between Station s 3870 and 5305

below the Forward Service/Emergency Door (Part 3).

Figure 6 Inspection area Forward

S/E d oor

Stgr 61

## Service Bulletin

Fokker 70/100

Jun 16/11 SBF100

- 53

- 115 Page 23

Copyr ight All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basis subject to the provisions of an agreement. Reproduction or disclosure to third parties of t his document or any part thereof, or the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. Round of the E dges of the R epair P atch and A erodynamically S eal the E dges (Part 4). Figure 7 Aerodynamically seal

all the edges Aerodynamically seal

all the edges 

## A A

Section 

## A

- 

## A

( before application of sealant )

Section 

## A

- 

## A

( after appl ication of sealant ) Round

- off edges ( R = t ) R t External repair patch

External repair patch

## Service Bulletin

Fokker 70/100

SBF100

- 53

- 115 Jun 16/11 Page 24

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basi s subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof , or the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is n ot per mitted except with the prior written permission of Fokker Services B.V. Temp orary R epair of the Frame Bays (Part 4). Figure 8 Repair p atch es made from 2024T3 Alclad ( t = 1,6 mm) NOTE S : LH side (stringer 12) drawn and RH side (stringer 61) opposite RH side stringer numbers are between parentheses

(STGR 61)

(STGR 61) (STGR 60) 

### Detail Z Only applicable to aircraft with a hinged ground

connection panel 127AB (refer to figure 9) DOF

## Service Bulletin

Fokker 70/100

Jun 16/11 SBF100

- 53

- 115 Page 25

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basis subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof, or the use of any information contained therein for purposes other than explicitly allo wed b y the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. Deviation of the T emporary R epair Patches at the E xternal R einforcement Doubler ( only applicable to A ircraft with a H inged G round C onnection P anel 127AB (Part 4) )

. Figure 9 S ta 4850 DOF Stgr 61

Stgr 62 External

reinforcement

doubler

## Service Bulletin

Fokker 70/100

SBF100

- 53

- 115 Jun 16/11 Page 26

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This document has been supplied by Fokker Services B.V. to its customers on a confidential basi s subject to the provisions of an agreement. Reproduction or disclosure to third parties of this document or any part thereof , or the use of any information contained therein for purposes other than explicitly allowed by the aforesaid agreement, is n ot per mitted except with the prior written permission of Fokker Services B.V. Operator:

Airc raft Serial Number:
Flight cycles : Flight hours :

Indicate on the figure the crack location direction and fill in the table the length

Crack number: S tgr n o : (12 or 61) Crack length: (mm or inch) Position*: (mm or inch)

* Distance FWD crack tip to nearest FWD frame.

Reporting F orm

. Figure 10 (STGR 61)

(STGR 61) (STGR 6 2 ) DOF

## S ervice B ulleti n Reporting Quality Form

Fokker 70/100

Jun 16/11 SBF100

- 53

- 115 Page 27

Copyright All rights reserved by Fokker Services B.V. (The Netherlands). This documen t has been supplied by Fokker Services B.V. to its customers on a confidential basis subject to the provisions of an agreemen t. Reproduction or disclosure to third parties of this document or any part thereof, or the use of any information contained the rei n for purposes other than explicitly allowed by the aforesaid agreement, is not permitted except with the prior written permission of Fokker Services B.V. 

## Service Bulletin Reporting Quality Form

Use this Service Bulletin Reporting Quality Form to tell us your perception of the quality of the Service Bulletin. The reported data tha t you provide to us will be used to analyze areas of difficulties and to take corrective actions to further improve the quality of our Service Bulletins. We thank you for the time you have taken in completing this form.

* Rate the scale of 1 to 4, with 1 the lowest score and 4 the highest score.

Chapters * 1 2 3 4

a) Quality rating of this SB (overall) □ □ □ □

b) Quality rating of the Planning Information □ □ □ □

c) Quality rating of the Material Information □ □ □ □

d) Quality rating of the Accompl ishment Instructions □ □ □ □

e) Quality rating of the Test Instructions (if applicable) □ □ □ □

f) Quality rating of the Illustrations or Drawings (if applicable) □ □ □ □

g) Timely delivery of the SB □ □ □ □

If you have had difficulties with one of the chapters of this Service Bulletin and/or one of your rating(s) is (are) lower than 3, please give a short description of the issue.

Comments:

Operator: Date:

Name / Title:

Please return this form to: Fokker Services B.V.

Techn ical Services, Quality Department

P.O. box 231

2150 AE Nieuw

- Vennep

The Netherlands