# Boeing Alert Requirements Bulletin 757-53A0123 RB: No revision named, part 3 of 4

- Rights: © The Boeing Company. Filed by the FAA in regulations.gov docket FAA-2025-0012; AD 2025-11-01 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [Boeing Alert Requirements Bulletin 757-53A0123 RB](https://openairdocs.org/service-documents/boeing/757-53a0123-rb.md)
- Title as filed: RB 757-53A0123 R0_Part3
- Pages: 33
- PDF: https://openairdocs.org/files/sha256/bb/d0/bbd07579ac93ed28d24fade547d0adbd4c8fcf73fffebd408c795b5cd823d9ae
- Page: https://openairdocs.org/service-documents/boeing/757-53a0123-rb/file/bbd07579ac93

## 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 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
FLOOR BEAM
FRAME REPAIR
ANGLE (NESTED  S-18R
INSIDE INNER
CHORD)
FRAME REPAIR
DOUBLER  FRAME OUTER
CHORD
NUT SPACER PLATES
MAY BE DIFFERENT
FOR EACH AIRPLANE  FAILSAFE
CONFIGURATION  CHORD
LOCATION 10
1.0
1.0
FRAME TRIM LINE
-S-19R
CHORD  FRAME INNER  • BEAR STRAP
• SKIN
FRAME WEB
FRAME REPAIR
FILLER
S-20R
INBD
(VIEW IN THE FORWARD DIRECTION AT FRAME WITH
FRAME SEGMENT REPLACEMENT REPAIR)
H-H
N GENERAL VISUAL INSPECTION  3051190
FIGURE 13: RIGHT SIDE - STA 1640 FRAME INNER CHORD, WEB AND OUTER CHORD - GENERAL
VISUAL INSPECTION (GVI)
(SHEET 10 OF 11)
Original Issue: March 13, 2024
Export Controlled ECCN: 9E991  757-53A0123 RB
See page 1 for details  140 of 178

### Page 2

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)(b)(c)--FRAMEInspect1
(d)(b)(c)--FRAMEInspect2
(a) Do a GVI for any approved frame segment replacement repair.
(b) It is not necessary to remove connecting frame structure to determine if a repair exists.
(c) A Maintenance records check is acceptable in lieu of the GVI inspection if the records review can conclu-
sively determine a repair exists in that location.
(d) Do a GVI for any local repair.
FIGURE 13: RIGHT SIDE - STA 1640 FRAME INNER CHORD, WEB AND OUTER CHORD - GENERAL
VISUAL INSPECTION (GVI)
(SHEET 11 OF 11)
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: March 13, 2024
757-53A0123 RB
141 of 178
REQUIREMENTS BULLETIN 757-53A0123
ALERTALERT

### Page 3 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
STA
STA  1640
1640
STA
1620
S-8R -
S-9R -
S-10R -
S-11R -
LOWER  S-13R
HINGE
INTERCOSTAL
S-14R
S-16R
FLOOR
FWD
S-17R -
(VIEW IN THE OUTBOARD DIRECTION)
FIGURE 14: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 BETWEEN S-9R AND S-10R - SURFACE
HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 1, APPROVED FRAME SEGMENT
REPLACEMENT REPAIR
(SHEET 1 OF 3)
Original Issue: March 13, 2024
Export Controlled ECCN: 9E991  757-53A0123 RB
See page 1 for details  142 of 178

### Page 4 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
S-9R
• SKIN
BRACKET
(BRACKET MAY
NOT EXIST ON
SOME AIRPLANE
_ CONFIGURATIONS)
FRAME REPAIR
/ DOUBLER
FRAME REPAIR  BEAR STRAP
ANGLE (NESTED
INSIDE INNER
CHORD)
FRAME OUTER
CHORD
FRAME WEB
FRAME REPAIR
FILLER
FRAME TRIM LINE •  UPPER HINGE
FITTING
FRAME INNER
CHORD
INBD
(VIEW IN THE FORWARD DIRECTION AT FRAME WITH
FRAME SEGMENT REPLACEMENT REPAIR)
A-A
SURFACE HFEC INSPECTION  3045686
FIGURE 14: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 BETWEEN S-9R AND S-10R - SURFACE
HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 1, APPROVED FRAME SEGMENT
REPLACEMENT REPAIR
(SHEET 2 OF 3)
Original Issue: March 13, 2024
Export Controlled ECCN: 9E991  757-53A0123 RB
See page 1 for details  143 of 178

### Page 5

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)(b)(c)--FRAME WEBInspect1
(a) Do a surface HFEC inspection around the rivet in the frame web at the plugged coordination hole (K-hole)
in the frame for any crack, from the aft side of the frame, in accordance with 757 NDT Manual Part 6, 51-
00-19.
(b) The adjacent bracket may interfere with the inspection probe. It is acceptable to do the inspection partially
around the fastener, stopping the probe at the point of interference with the bracket.
(c) Some airplane configurations may not have the K-hole at this location. The surface HFEC inspection is
not required for any airplane with no plugged K-hole at this location.
FIGURE 14: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 BETWEEN S-9R AND S-10R - SURFACE
HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 1, APPROVED FRAME SEGMENT
REPLACEMENT REPAIR
(SHEET 3 OF 3)
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: March 13, 2024
757-53A0123 RB
144 of 178
REQUIREMENTS BULLETIN 757-53A0123
ALERTALERT

### Page 6 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
STA
STA  1640
1640
SIA
1620
S-8R •
S-9R
S-10R
S-11R
LOWER  S-13R •
HINGE
INTERCOSTAL
S-14R-
S-16R
FWD
FLOOR
S-17R -
(VIEW IN THE OUTBOARD DIRECTION)
3045690
FIGURE 15: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 BETWEEN S-9R AND S-10R - OPEN-HOLE
HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 1, NO EXISTING REPAIR
(SHEET 1 OF 3)
Original Issue: March 13, 2024
Export Controlled ECCN: 9E991  757-53A0123 RB
See page 1 for details  145 of 178

### Page 7 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
S-9R
SKIN \
BRACKET
(BRACKET MAY
NOT EXIST ON
SOME AIRPLANE
CONFIGURATIONS)
BEAR STRAP
FRAME OUTER
CHORD
FRAME WEB
UPPER HINGE
FITTING
FRAME INNER
CHORD
INBD
(VIEW IN THE AFT DIRECTION AT FRAME WITHOUT
FRAME SEGMENT REPLACEMENT REPAIR)
A-A
OPEN-HOLE HIGH FREQUENCY  3045691
EDDY CURRENT INSPECTION
FIGURE 15: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 BETWEEN S-9R AND S-10R - OPEN-HOLE
HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 1, NO EXISTING REPAIR
(SHEET 2 OF 3)
Original Issue: March 13, 2024
757-53A0123 RB
Export Controlled ECCN: 9E991
See page 1 for details  146 of 178

### Page 8

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)(b)1-FRAME WEBInspect1
(a) Do an open-hole HFEC inspection of the K-hole in the frame web for any crack in accordance with 757
NDT Manual Part 6, 51-00-04, 757 NDT Manual Part 6, 51-00-11 or 757 NDT Manual Part 6, 51-00-16.
(b) Some airplane configurations may not have the K-hole at this location. The open-hole HFEC inspection
is not required for any airplane with no K-hole at this location.
FIGURE 15: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 BETWEEN S-9R AND S-10R - OPEN-HOLE
HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 1, NO EXISTING REPAIR
(SHEET 3 OF 3)
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: March 13, 2024
757-53A0123 RB
147 of 178
REQUIREMENTS BULLETIN 757-53A0123
ALERTALERT

### Page 9 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
SIA
STA  1640
1640
STA
1620
Le bale
S-8R
S-9R-
S-10R •
S-11R -
LOWER S-13R
HINGE
INTERCOSTAL
S-14R
S-16R
FLOOR
FWD
S-17R -
(VIEW IN THE OUTBOARD DIRECTION)
FIGURE 16: RIGHT SIDE - FUSELAGE FRAME INNER CHORD AT STA 1640 BETWEEN S-10R AND S-11R
- SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 2, NO EXISTING
REPAIR
(SHEET 1 OF 3)
Original Issue: March 13, 2024
757-53A0123 RB
Export Controlled ECCN: 9E991
See page 1 for details  148 of 178

### Page 10 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
STA
1640
INTERCOSTAL
STRAP
S-10R
S-11R
COVER
PLATE
FWD
(VIEW IN THE OUTBOARD DIRECTION)  COVER
PLATE
INTERCOSTAL
FRAME  STRAP
INNER
CHORD
S-10R
A-A
INTERCOSTAL
STRAP
FRAME
INNER
A SURFACE HFEC INSPECTION  B-B  CHORD  3045701
FIGURE 16: RIGHT SIDE - FUSELAGE FRAME INNER CHORD AT STA 1640 BETWEEN S-10R AND S-11R
- SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 2, NO EXISTING
REPAIR
(SHEET 2 OF 3)
Original Issue: March 13, 2024
757-53A0123 RB
Export Controlled ECCN: 9E991
See page 1 for details  149 of 178

### Page 11

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)--FRAME INNER
CHORD
Inspect1
(a) Do a surface HFEC inspection of the frame inner chord around each of the three fasteners for any crack
in accordance with 757 NDT Manual Part 6, 51-00-19.
FIGURE 16: RIGHT SIDE - FUSELAGE FRAME INNER CHORD AT STA 1640 BETWEEN S-10R AND S-11R
- SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 2, NO EXISTING
REPAIR
(SHEET 3 OF 3)
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: March 13, 2024
757-53A0123 RB
150 of 178
REQUIREMENTS BULLETIN 757-53A0123
ALERTALERT

### Page 12 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
STA
STA  1640
1640
S-8R -
S-9R •
A Or B
S-10R
S-11R
LOWER  S-13R
HINGE
INTERCOSTAL
S-14R -
S-16R
FWD
FLOOR
S-17R -
(VIEW IN THE OUTBOARD DIRECTION)
3045705
FIGURE 17: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 AND S-10R - OPEN-HOLE HIGH
FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 3
(SHEET 1 OF 4)
Original Issue: March 13, 2024
Export Controlled ECCN: 9E991  757-53A0123 RB
See page 1 for details  151 of 178

### Page 13 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
UPPER HINGE
FRAME WEB  FITTING
UPPER HINGE
FLAP
FRAME INNER
CHORD  • UPPER SKIN
S-10R
INTERCOSTAL  OE3 LOCATIONS
STRAP
• BEAR STRAP
+  • LOWER SKIN
FRAME OUTER
CHORD
+
(VIEW IN THE FORWARD DIRECTION AT FRAME
WITHOUT FRAME SEGMENT REPLACEMENT REPAIR)
A-A
I OPEN-HOLE HIGH FREQUENCY  3045707
EDDY (HFEC) INSPECTION
FIGURE 17: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 AND S-10R - OPEN-HOLE HIGH
FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 3
(SHEET 2 OF 4)
Original Issue: March 13, 2024
757-53A0123 RB
Export Controlled ECCN: 9E991
See page 1 for details  152 of 178

### Page 14 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
, UPPER HINGE
FRAME WEB  FITTING
UPPER HINGE
FRAME INNER  _ FLAP
CHORD  UPPER SKIN
- S-10R
INTERCOSTAL  1E 3 LOCATIONS
STRAP
BEAR STRAP
LOWER SKIN
FRAME OUTER
CHORD
FRAME REPAIR
DOUBLER
FRAME REPAIR
ANGLE (NESTED
INSIDE INNER
NBI  CHORD)
(VIEW IN THE FORWARD DIRECTION AT FRAME WITH
FRAME SEGMENT REPLACEMENT REPAIR)
A-A
/ OPEN-HOLE HIGH FREQUENCY  3051200
EDDY (HFEC) INSPECTION
FIGURE 17: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 AND S-10R - OPEN-HOLE HIGH
FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 3
(SHEET 3 OF 4)
Original Issue: March 13, 2024
757-53A0123 RB
Export Controlled ECCN: 9E991
See page 1 for details  153 of 178

### Page 15

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)3-FASTENERRemove / Keep1
(b)(c)(d)--FRAME WEBInspect2
(a) Refer to 757-200 SRM 51-40-02, 757-200CB SRM 51-40-02 or 757-300 SRM 51-40-02 as an accepted
procedure.
(b) Do an open-hole HFEC inspection of the frame web at each of the three (3) open holes for any crack in
accordance with 757 NDT Manual Part 6, 51-00-04, 757 NDT Manual Part 6, 51-00-11 or 757 NDT
Manual Part 6, 51-00-16.
(c) Insert the probe to a minimum depth of 0.30 inches to reach the entire thickness of the frame web, and
to a maximum depth of 0.40 inches to avoid interfering with the nutplate.
(d) Do the open hole inspection from the aft side of the frame through the external access door or the hinge
opening.
FIGURE 17: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 AND S-10R - OPEN-HOLE HIGH
FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 3
(SHEET 4 OF 4)
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: March 13, 2024
757-53A0123 RB
154 of 178
REQUIREMENTS BULLETIN 757-53A0123
ALERTALERT

### Page 16 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
STA
STA  1640
1640
000
S-8R -
S-9R
S-10R
S-11R  A or B
A or B
0000
S-13R
LOWER
HINGE
INTERCOSTAL
S-14R
S-16R
FWD
FLOOR
S-17R -
(VIEW IN THE OUTBOARD DIRECTION)
3045708
FIGURE 18: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 BETWEEN S-11R AND S-13R -
SUB-SURFACE LOW FREQUENCY EDDY CURRENT (LFEC) INSPECTION - LOCATIONS 4 AND 5
(SHEET 1 OF 4)
Original Issue: March 13, 2024
Export Controlled ECCN: 9E991  757-53A0123 RB
See page 1 for details  155 of 178

### Page 17 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
S-11R
DOUBLER
INTERCOSTAL
STRAP
BRACKET
• FRAME WEB
~ FRAME INNER
PRESSURE SEAL  CHORD
FITTING
- -
FRAME OUTER
CHORD
• COVER PLATE
BEAR STRAP
SKIN
S-13R
INTERCOSTAL
STRAP
INBD
(VIEW IN THE AFT DIRECTION)
A-A
SUBSURFACE LFEC INSPECTION  3045710
FIGURE 18: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 BETWEEN S-11R AND S-13R -
SUB-SURFACE LOW FREQUENCY EDDY CURRENT (LFEC) INSPECTION - LOCATIONS 4 AND 5
(SHEET 2 OF 4)
Original Issue: March 13, 2024
757-53A0123 RB
Export Controlled ECCN: 9E991
See page 1 for details  156 of 178

### Page 18 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
S-11R ~
DOUBLER •  INTERCOSTAL
STRAP
BRACKET
FRAME WEB
FRAME INNER
PRESSURE SEAL  CHORD
FITTING
FRAME OUTER
CHORD
COVER PLATE
BEAR STRAP
SKIN
S-13R•
INTERCOSTAL
STRAP
INBD
(VIEW IN THE AFT DIRECTION)
B-B
SUBSURFACE LFEC INSPECTION  3045711
FIGURE 18: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 BETWEEN S-11R AND S-13R -
SUB-SURFACE LOW FREQUENCY EDDY CURRENT (LFEC) INSPECTION - LOCATIONS 4 AND 5
(SHEET 3 OF 4)
Original Issue: March 13, 2024
Export Controlled ECCN: 9E991  757-53A0123 RB
See page 1 for details  157 of 178

### Page 19

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)(b)(c)--FRAME WEBInspect1
(a) Do a subsurface LFEC inspection of the frame web through the doubler around each of the two fasteners
for any crack, from the forward side, in accordance with 757 NDT Manual Part 6, 51-00-23.
(b) The frame web is 0.080 inches thick and the doubler steps down from 0.090 inches to 0.040-0.060 inches
thick in the inspection area.
(c) AF-4087 is an optional smaller LFEC probe that can be used around fasteners with a short edge distance.
FIGURE 18: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 BETWEEN S-11R AND S-13R -
SUB-SURFACE LOW FREQUENCY EDDY CURRENT (LFEC) INSPECTION - LOCATIONS 4 AND 5
(SHEET 4 OF 4)
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: March 13, 2024
757-53A0123 RB
158 of 178
REQUIREMENTS BULLETIN 757-53A0123
ALERTALERT

### Page 20 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
STA
STA  1640
1640
1000
S-8R -
S-9R •
S-10R
S-11R
S-13R
LOWER
HINGE
INTERCOSTAL
S-14R
000
S-16R  ....
FWD
FLOOR
S-17R -
(VIEW IN THE OUTBOARD DIRECTION)
3045713
FIGURE 19: RIGHT SIDE - FUSELAGE FRAME INNER CHORD AT STA 1640 BETWEEN S-11R AND S-13R
- SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 6
(SHEET 1 OF 3)
Original Issue: March 13, 2024
Export Controlled ECCN: 9E991  757-53A0123 RB
See page 1 for details  159 of 178

### Page 21 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
STA
1640
S- 11R
COVER
PLATE
S-13R -
(VIEW IN THE OUTBOARD DIRECTION)
FRAME
INNER
CHORD
COVER
FRAME  PLATE
INNER
CHORD
COVER
PLATE
A-A
(VIEW IN THE INBOARD DIRECTION)  3045714
A SURFACE HFEC INSPECTION  B-B
FIGURE 19: RIGHT SIDE - FUSELAGE FRAME INNER CHORD AT STA 1640 BETWEEN S-11R AND S-13R
- SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 6
(SHEET 2 OF 3)
Original Issue: March 13, 2024
757-53A0123 RB
Export Controlled ECCN: 9E991
See page 1 for details  160 of 178

### Page 22

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)--FRAME INNER
CHORD
Inspect1
(a) Do a surface HFEC inspection of the frame inner chord around each of the three fasteners for any crack
in accordance with 757 NDT Manual Part 6, 51-00-19.
FIGURE 19: RIGHT SIDE - FUSELAGE FRAME INNER CHORD AT STA 1640 BETWEEN S-11R AND S-13R
- SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 6
(SHEET 3 OF 3)
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: March 13, 2024
757-53A0123 RB
161 of 178
REQUIREMENTS BULLETIN 757-53A0123
ALERTALERT

### Page 23 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
This Figure applies only to: Group 1-3.
STA
STA  1640
1640
STA
1620
S-8R
S-9R
A
S-10R -
S-11R -
LOWER S-13R
HINGE
INTERCOSTAL
S-14R
S-16R -
-WD
FLOOR
S-17R -
(VIEW IN THE OUTBOARD DIRECTION)
3045717
FIGURE 20: RIGHT SIDE - FUSELAGE FRAME INNER CHORD AT STA 1640 BETWEEN S-13R AND S-14R
- SUBSURFACE LOW FREQUENCY EDDY CURRENT (LFEC) INSPECTION - LOCATION 7
(SHEET 1 OF 4)
Original Issue: March 13, 2024
757-53A0123 RB
Export Controlled ECCN: 9E991
See page 1 for details  162 of 178

### Page 24 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
INNER CHORD
/ STRAP
LOWER HINGE
• INTERCOSTAL
STRAP
- FRAME INNER
CHORD
—S-14R
• INTERCOSTAL
STRAP
(SOME PARTS ARE REMOVED)
3051218
FIGURE 20: RIGHT SIDE - FUSELAGE FRAME INNER CHORD AT STA 1640 BETWEEN S-13R AND S-14R
- SUBSURFACE LOW FREQUENCY EDDY CURRENT (LFEC) INSPECTION - LOCATION 7
(SHEET 2 OF 4)
Original Issue: March 13, 2024
Export Controlled ECCN: 9E991  757-53A0123 RB
See page 1 for details  163 of 178

### Page 25 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
INNER CHORD
STRAP
/ CHORD  FRAME INNER
LOWER HINGE -
INTERCOSTAL
STRAP
→ 0.08
0.045 -
(SOME PARTS ARE REMOVED)
A-A
SUBSURFACE LFEC INSPECTION  3045719
FIGURE 20: RIGHT SIDE - FUSELAGE FRAME INNER CHORD AT STA 1640 BETWEEN S-13R AND S-14R
- SUBSURFACE LOW FREQUENCY EDDY CURRENT (LFEC) INSPECTION - LOCATION 7
(SHEET 3 OF 4)
Original Issue: March 13, 2024
757-53A0123 RB
Export Controlled ECCN: 9E991
See page 1 for details  164 of 178

### Page 26

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)(b)--FRAME INNER
CHORD
Inspect1
(a) Do subsurface LFEC inspection of the frame inner chord through the inner chord strap for any crack in
accordance with 757 NDT Manual Part 6, 51-00-23.
(b) AF-4087 is an optional smaller LFEC probe that can be used around fasteners with a short edge distance.
FIGURE 20: RIGHT SIDE - FUSELAGE FRAME INNER CHORD AT STA 1640 BETWEEN S-13R AND S-14R
- SUBSURFACE LOW FREQUENCY EDDY CURRENT (LFEC) INSPECTION - LOCATION 7
(SHEET 4 OF 4)
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: March 13, 2024
757-53A0123 RB
165 of 178
REQUIREMENTS BULLETIN 757-53A0123
ALERTALERT

### Page 27 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
STA
STA  1640
1640
STA
1620
S-8R -
S-9R -
S-10R -
S-11R -
LOWER  S-13R-
HINGE
INTERCOSTAL
S-14R
0000
S-16R
FWD
FLOOR
S-17R -
(VIEW IN THE OUTBOARD DIRECTION)
FIGURE 21: RIGHT SIDE - FUSELAGE FRAME WEB AND OUTER CHORD AT STA 1640 BELOW S-13R -
SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 8, AIRPLANES WITH
A BACKUP FITTING INSTALLED
(SHEET 1 OF 3)
Original Issue: March 13, 2024
Export Controlled ECCN: 9E991  757-53A0123 RB
See page 1 for details  166 of 178

### Page 28 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
S-13R-
CHEM MILL POCKET
(THE CHEM MILL
FEATURE MAY NOT
EXIST ON SOME
AIRPLANE
CONFIGURATIONS)
0.50 | 1|1
B  0.50
BACKUP /
FITTING
FRAME  FRAME
OUTER  WEB
CHORD
LOWER
HINGE
INTERCOSTAL
(VIEW IN THE AFT DIRECTION)  INBD
A-A
FRAME
SUPPORT  BACKUP  OUTER
FITTING  FITTING  CHORD
SUPPORT
FITTING
0.50
FRAME
WEB
BACKUP
FITTING
FRAME  0.50
OUTER
CHORD
FWD  FRAME
WEB
(VIEW IN THE DOWN DIRECTION)  (VIEW IN THE OUTBOARD DIRECTION)
B-B  C-C
• SURFACE HFEC INSPECTION  3045722
* SUBSURFACE LFEC INSPECTION
FIGURE 21: RIGHT SIDE - FUSELAGE FRAME WEB AND OUTER CHORD AT STA 1640 BELOW S-13R -
SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 8, AIRPLANES WITH
A BACKUP FITTING INSTALLED
(SHEET 2 OF 3)
Original Issue: March 13, 2024
757-53A0123 RB
Export Controlled ECCN: 9E991
See page 1 for details  167 of 178

### Page 29

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)(b)--FRAME WEBInspect1
(c)--FRAME OUTER
CHORD
Inspect2
(d)(e)--FRAME OUTER
CHORD
Inspect3
(a) Do a surface HFEC inspection of the frame web along the edge of the backup fitting for any crack in ac-
cordance with 757 NDT Manual Part 6, 51-00-19.
(b) For airplanes with a chem-milled pocket in the frame web, inspect along the edge of the chem-milled step.
For airplanes without a chem-milled step, use the backup fitting as a guide to inspect the frame web.
(c) Do a surface HFEC inspection of the frame outer chord edge for any crack in accordance with 757 NDT
Manual Part 6, 51-00-19. Use special probe, AXTPN-95-5 or AXPN-95-5.
(d) Do a subsurface LFEC inspection of the outer chord outboard flange through the backup fitting for any
crack in accordance with 757 NDT Manual Part 6, 51-00-23.
(e) Outer chord outboard flange is 0.16 inches thick and the backup fitting is 0.10 inches thick.
FIGURE 21: RIGHT SIDE - FUSELAGE FRAME WEB AND OUTER CHORD AT STA 1640 BELOW S-13R -
SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 8, AIRPLANES WITH
A BACKUP FITTING INSTALLED
(SHEET 3 OF 3)
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: March 13, 2024
757-53A0123 RB
168 of 178
REQUIREMENTS BULLETIN 757-53A0123
ALERTALERT

### Page 30 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
STA
STA  1640
1640
S-8R -
S-9R
S-10R
S-11R
LOWER  S-13R
HINGE
INTERCOSTAL
S-14R
S-16R
FWD
FLOOR
S-17R -
(VIEW IN THE OUTBOARD DIRECTION)
FIGURE 22: RIGHT SIDE - FUSELAGE FRAME WEB AND OUTER CHORD AT STA 1640 BELOW S-13R -
SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 8, AIRPLANES WITHOUT
A BACKUP FITTING INSTALLED
(SHEET 1 OF 3)
Original Issue: March 13, 2024
757-53A0123 RB
Export Controlled ECCN: 9E991
See page 1 for details  169 of 178

### Page 31 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
S-13R
SUPPORT
FITTING
0.5
0.50
FRAME WEB
FRAME OUTER
CHORD
LOWER
HINGE
INTERCOSTAL
INBD
(VIEW IN THE AFT DIRECTION)
A-A
/ SURFACE HFEC INSPECTION  3045724
FIGURE 22: RIGHT SIDE - FUSELAGE FRAME WEB AND OUTER CHORD AT STA 1640 BELOW S-13R -
SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 8, AIRPLANES WITHOUT
A BACKUP FITTING INSTALLED
(SHEET 2 OF 3)
Original Issue: March 13, 2024
Export Controlled ECCN: 9E991  757-53A0123 RB
See page 1 for details  170 of 178

### Page 32

The step numbers shown below agree with the numbers shown in the circle symbols in the figure. The QTY
numbers shown below are the number of parts necessary for this figure.
More DataQtyIdentificationNameTaskStep
(a)--FRAME WEBInspect1
(b)--FRAME OUTER
CHORD
Inspect2
(a) Do a surface HFEC inspection of the frame web along the edge of the frame outer chord for any crack in
accordance with 757 NDT Manual Part 6, 51-00-19.
(b) Do a surface HFEC inspection of the frame outer chord around the fastener for any crack in accordance
with 757 NDT Manual Part 6, 51-00-19.
FIGURE 22: RIGHT SIDE - FUSELAGE FRAME WEB AND OUTER CHORD AT STA 1640 BELOW S-13R -
SURFACE HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 8, AIRPLANES WITHOUT
A BACKUP FITTING INSTALLED
(SHEET 3 OF 3)
Export Controlled ECCN: 9E991
See page 1 for details
Original Issue: March 13, 2024
757-53A0123 RB
171 of 178
REQUIREMENTS BULLETIN 757-53A0123
ALERTALERT

### Page 33 (OCR)

REQUIREMENTS BULLETIN 757-53A0123
ALERT  ALERT
STA
STA  1640
1640
STA
1620
S-8R -
S-9R -
S-10R -
S-11R -
LOWER  S-13R
HINGE
INTERCOSTAL
S-14R -
S-16R -
FWD
FLOOR
S-17R -
(VIEW IN THE OUTBOARD DIRECTION)
3045725
FIGURE 23: RIGHT SIDE - FUSELAGE FRAME WEB AT STA 1640 LOWER HINGE FITTING - OPEN-HOLE
HIGH FREQUENCY EDDY CURRENT (HFEC) INSPECTION - LOCATION 9
(SHEET 1 OF 3)
Original Issue: March 13, 2024
757-53A0123 RB
Export Controlled ECCN: 9E991
See page 1 for details  172 of 178

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