April 5/13 Rev. NC Service Bulletin 215-A558

Page 1 of 23 ATA Ref: 57−10

MODEL CL-215-1A10

MODEL CL-215-6B11

ALERT

SERVICE BULLETIN

FUSELAGE

INSPECTION OF THE LOWER FRONT AND REAR LOWER SPAR CAP FROM BL 45.00 TO BL 51.00

1. Planning Information

A. Compliance

The inspections as described in this Service Bulletin are Mandatory. The repetitive detailed

inspection (PART A) must be completed within 10 flight hours upon receipt of this Service

Bulletin. Subsequently, the repetitive detailed inspection must be completed every 25 flight

hours there after until either the one−time detailed inspection (PART B) or the eddy current

inspection (PARTS C−1 and C−2) have been carried out.

NOTES: 1. The inspections described in this Service Bulletin is an interim solution and is not

meant to replace Service Bulletins 215−A454 and/or 215−A463. The compliance

in those two Service Bulletins must still be complied with and those two Service

Bulletins will be revised in the near future to introduce new inspection

procedures.

2. This Service Bulletin is only applicable to aircraft in the condition as originally

delivered by Canadair and/or Bombardier Aerospace or as subsequently modified

by Canadair and/or Bombardier Aerospace Service Bulletin(s). Prior to

incorporation of this Service Bulletin, the status of any related systems or

structural modification(s) introduced by Supplementary Type Approval (STA) or

equivalent action must be examined for compatibility with the modifications and

test procedures (if applicable) detailed in this Service Bulletin. 

B. Approval

The technical content of this Service Bulletin has been approved under the authority of the

Design Approval Organization No: DAO #93-Q-02.
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C. Effectivity

CL−215−1A10 piston and CL−215−6B11 turboprop aircraft, Serial Nos. 1001 to1125.

D. Reason

An operator reported damage to the rear spar cap, spar web, and lower wing skin of the

aircraft. This damage was noticed 95 hours after an ultrasonic inspection carried out by

Service Bulletin 215−A454 which is mandated by AD CF−1992−26R2. It is assumed that this

inspection may not have been adequate to detect a spar cap crack. As a result, a fleet wide

check of the CL−215 and CL−215T aircraft is required. The initial and subsequent

inspections will be done via a repetitive detailed inspection of the wing lower skin until either an

eddy current or a one−time detailed inspection is performed as described in this Service

Bulletin.

E. Description

This Service Bulletin provides instructions to do a repetitive detailed inspection, a one−time

detailed inspection and an eddy current inspection of the wing front and rear spar at the

attachments to the fuselage.

F. Manpower

We estimate that it will take 1 person approximately 2 hours to do the repetitive detailed

inspection (PART A).

We estimate that it will take 2 person approximately 20 hours to do the one−time detailed

inspection (PART B).

The estimated time to complete the eddy current inspection is as follows (PART C−1 and C−2):

NOTE: This inspection shall only be performed by personnel trained and certified to the Eddy

Current Testing (ET) Level II or Level III certified to NAS 410 (EN4179) or equivalent.

Approximately 3 man−hours are required to perform the eddy current inspection on the

front and rear spar frame−angles on the piston aircraft.

Approximately 2.5 man−hours are required to perform the eddy current inspection on the

front and rear spar frame−angles on the turboprop aircraft.

G. Material Availability

This Service Bulletin contains no kit.
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April 5/13 Rev. NC Service Bulletin 215-A558

Page 3 of 23 ATA Ref: 57−10

H. Tool Availability

Bombardier Inc. / Canadair Reference Standard No. AL35−45, aluminum alloy (35−45% IACS)

containing a 0.008−inch (0,20−millimetres), a 0.020−inch (0,51−millimeters), and a 0.040−inch

(1,02−millimeter) deep electric discharge machining (EDM) notch or equivalent.

Commercially Available − Coaxial Cable, BNC to Microdot

Commercially Available − Explosion proof light source

Commercially Available − Inspection mirror

Olympus NDT NEC−2261 Surface Blade Probe, flexible copper shaft, 50−500kHz frequency,

Fe/NFe, absolute, shielded, 0.045 inch (1,14 millimeters) thick, 6.0 inch (152,4 millimeters)

blade length

Hocking Phasec 2200 − Eddy Current−Instrument−Impedance−Plane Type

NOTE: Equivalent Eddy Current equipment may be used provided that it satisfies the

requirement of this Procedure. The equipment must be capable of resolving the

reference notch in the calibration standard at the required level of resolution and

sensitivity.

To get access to the inspection area due to accessibility or to user preference, it is

permissible to use a probe of different configuration from the one specified. The test

frequency used may range from 100 kHz to 2.0 MHz for surface inspection.

I. Weight and Balance

Not affected.

J. Electrical Load Data

Not affected.

K. References

For Bombardier Aerospace Reference only:

(Not Supplied with Kit)

Bombardier Aerospace Restriction and/or Special Instruction (RSI) C-3933, Revision NC.
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April 5/13 Rev. NC Service Bulletin 215-A558

Page 4 of 23 ATA Ref: 57−10

L. Publications Affected

PSP 297, Structural Repair Manual, Chapter 53−10−31

PSP 296, NDTM, Part 1, 51−00−30

Part 1, 51−00−40

Part 1, 51−15−03

M. Related Service Bulletin

215−A454 SPECIAL REWORK AND/OR INSPECTION OF THE REAR SPAR LOWER CAP 

AND THE WING LOWER SKIN AT WING STATION (WS) 51.00

215−A463 SPECIAL INSPECTION AND REWORK OF THE FRONT SPAR LOWER CAP AT 

WING STATION 51.00

NOTES: 1. For this modification, it is assumed that standard maintenance and repair practices

will be applied in accordance with applicable PSP’s.

2. Refer to the various views in this Service Bulletin for the locations to be inspected.

N. Preparation

WARNING: ENSURE PERSONNEL AND EQUIPMENT ARE CLEAR OF ALL

HYDRAULICALLY OPERATED SYSTEMS PRIOR TO REMOVING ELECTRICAL

POWER. IF YOU DO NOT DO THIS, INJURIES TO PERSONNEL AND

DAMAGE TO EQUIPMENT CAN OCCUR.

(1) Isolate electrical power and observe all safety precautions.

(a) For CL-215T aircraft, refer to PSP 392, Aircraft Maintenance Manual,

Chapter 24−00−00, ELECTRICAL POWER − MAINTENANCE PRACTICES.

(b) For CL-215 aircraft, set the MASTER switch on the DC POWER control panel to

GPU/BATT then unscrew and disconnect the battery connector. Refer to PSP 292,

Aircraft Maintenance Manual, Chapter 24−00−00, ELECTRICAL POWER −

MAINTENANCE PRACTICES.
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April 5/13 Rev. NC Service Bulletin 215-A558

Page 5 of 23 ATA Ref: 57−10

2. PART A − REPETITIVE DETAILED INSPECTION (DI) − WING LOWER SKIN WS 45.00 TO

51.00

NOTE: This repetitive detailed inspection is mandated to be repeated every 25 flight hours until

the one−time detailed inspection described in PART B, or the eddy current inspection

described in PARTS C−1 and C−2 of the front and rear spar caps are completed.

Detailed Inspection (DI) Definition

An intensive visual examination of a specific structural area, installation or assembly to detect

damage, failure or irregularity. Available lighting is normally supplemented with a direct source of

good lighting at an intensity deemed appropriate by the inspector. Inspection aids such as mirrors,

magnifying lenses, etc. may be used. Surface cleaning and elaborate access procedure may be

required.

A. Procedure

Refer to Figure 1

(1) Open the access panel 330-1 (340-1 right) to gain access to the spaces below the lower

wing skin and the fuselage roof skin.

(2) Using suitable lighting and with the aid of an inspection mirror or borescope camera,

search for indications of cracks on the lower wing skins.

NOTE: The cracks may be expected to emerge from the area of the wing-to-fuselage

joint angles and propagate longitudinally (fore and aft).

(3) Record and report the inspection findings to Bombardier Aerospace Specialized and

Amphibious Aircraft Customer Support.

(4) Close the access panel 330-1 (340-1 right).

3. PART B − ONE-TIME DETAILED INSPECTION (DI) WING LOWER SKIN WS 45.00 TO WS 55.00

NOTE: This one-time DI is an acceptable alternative to the eddy current inspection of the front and

rear spar caps.

A. Procedure

(1) Remove the No. 2 fuel cell and associated liner (left and right side). Refer to the

PSP 292 Aircraft Maintenance Manual, Chapter 28−11−01 FUEL CELLS −

REMOVAL/INSTALLATION, paragraph A.
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(2) Using suitable lighting and inspection aids such as an inspection mirror or a borescope

camera, inspect the following for cracks:

− wing lower skin

− front and rear spar webs

− front and rear spar caps

− re-enforcing straps

NOTE: Pay particular attention to the edges of the spar caps as the re-enforcing straps

may mask cracks.

(3) Record and report the inspection findings to your Bombardier Aerospace Specialized and

Amphibious Aircraft Technical Representative.

(4) Install the No. 2 fuel cell and associated liner (left and right side). Refer to the PSP 292,

Aircraft Maintenance Manual, Chapter 28−11−01 FUEL CELLS −

REMOVAL/INSTALLATION, paragraph B.

B. PART C−1 − EDDY CURRENT INSPECTION − LOWER FRONT SPAR CAP

Preparation and Cleaning:

(1) Remove access panels 310−1, 310−2, 721−3, and 821−3. Refer to PSP 292,

Chapter 6−51−00, ACCESS PANELS − DESCRIPTION AND OPERATIONS.

(2) Locate and identify all areas of the front lower spar cap that require inspection. Refer to

Figure 2.

(3) This inspection must be performed from the forward side of the wing front spar.

(4) Clean the areas to be tested thoroughly with aliphatic naphtha using a nylon bristled

brush and clean cloths. Allow the inspection surfaces to dry completely.

NOTE: If the paint or primer condition is good, it need not be removed. If the finish is

damaged, the bare metal must be exposed and refinished in accordance with

PSP 297, Structural Repair Manual, Chapter 51−52−16, CORROSION

PREVENTIVE TREATMENT − PROCEDURES.
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Page 7 of 23 ATA Ref: 57−10

4. Equipment Calibration for the Inspection of Surface Cracks in the Wing Lower Front Spar Cap

A. Eddy Current Calibration Procedure

(1) Use a coaxial cable to connect the surface pencil probe to the Eddy Current instrument.

(2) Turn the instrument [ON]. Set and adjust the instrument controls as noted in TABLE 1

Calibration Data, Instrument Settings.

(3) Place the probe tip perpendicular to the surface of the calibration reference standard

(CRS) AL35−45 away from the 0.040−inch (1.02 mm) EDM notch and the edge. Refer to

Figure 2.

NOTE: Avoid tilting the probe tip, this could result in a false indication.

(4) Balance (BAL) the instrument, and adjust the PHASE (ROTATION) control knob until a

horizontal lift−off signal moving from right to left is obtained with increasing lift−off across

the screen display.

(5) Slide the probe across the 0.040-inch deep electro-discharge machining (EDM) notch

while maintaining the probe coil perpendicular to the inspection surface at all times.

Adjust the instrument sensitivity [GAIN] to obtain an amplitude signal as shown in TABLE

1 Calibration Data, Instrument Settings.

(6) Differentiate between the edge and the notch signals by sliding the probe off the edge of

the reference standard. The signal obtained from the edge shall slant−off towards the

upper left quadrant as shown in TABLE 1 Calibration Data, Instrument Settings.

(7) If the inspection area is painted, carry out the lift−off compensation prior to inspection.

Refer to Step 4.B.

Table 1

Calibration Data

LIFT−OFF SIGNAL BALANCE POINT

EDGE SIGNAL SIGNAL FROM 0.040 in (1,02 mm)

EDM NOTCH

80%

FSH

100%

0%

Mode ABS, Ch 1

Display XY

View Ch 1

Ch 1 Frequency 500 kHz

Ch 1 Phase 301.0

Ch 1 Gain 46 dB

Ch 1 X:Y X − 8 dB

Hi − Pass DC

Lo − Pass 200 Hz

Balance Load 47 

X − Pos 40

Y − Pos −40

Table 1 − Calibration Data

Instrument Settings Screen Display

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Page 8 of 23 ATA Ref: 57−10

B. Lift-Off Compensation Calibration

(1) After the calibration, put the probe (coil) tip perpendicular to the inspection surface. Do

not balance the instrument at this step.

(2) Compare the screen displays between the operating point on the inspection surface and

the balance point on the CRS.

(3) If the operating point on the inspection surface matches the balance point on the CRS, no

compensation for the paint thickness is required. Proceed to the inspection procedure,

Section 6.

(4) If the operating point on the inspection surface does not match the balance point on the

CRS, but has moved to the left on the display screen, compensation for the paint

thickness is required.

Do as follows:

(a) Attach a strip of nonconductive tape or shim to cover the CRS surface, including the

EDM notches.

(b) Put the probe (coil) tip perpendicular to the surface of the CRS, away from the EDM

notch and part edge. Rebalance the instrument and compare the operating point on

the inspection surface to the balance point on the CRS as shown on the instrument

display screen.

(c) If the operating point on the inspection surface is left of the balance point on the

CRS, add an additional strip of tape (thickness) or shim until the balance point on

the CRS matches that of the operating point of the inspection area.

(d) If the operating point on the inspection surface is to the right of the balance point on

the CRS with the tape applied, remove a strip of tape or shim until the balance point

on the CRS matches the operating point of the inspection area.

(e) If lift-off compensation and calibration requirements cannot be met, remove the paint

or other coatings from the inspection surface prior to the inspection.

(5) Slide the probe (coil) tip across the 0.040-inch (1,02-millimeter) deep EDM notch covered

with tape on the CRS.

(6) Adjust the [GAIN] to obtain an eddy current amplitude signal from the 0.040-inch

(1,02-millimeter) deep EDM notch as shown in Table 1 Calibration Data, screen display.

(7) Proceed to the inspection procedure. MODEL CL-215-1A10

MODEL CL-215-6B11

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SERVICE BULLETIN

April 5/13 Rev. NC Service Bulletin 215-A558

Page 9 of 23 ATA Ref: 57−10

5. Inspection of the Wing Lower Front Spar

NOTE: Monitor the test instrument screen display carefully at all times and make note of all

distinct, relevant indications: The screen amplitude of each signal and its relative location

on the inspection surface.

After the balancing in the inspection area, if the balance point drops below the screen display from

the original balance point, it could indicate the original balance location contains a defect. In such

a case, rebalance the instrument on an adjacent area and scan the original balance point for

possible defects before continuing the inspection.

Verify the instrument calibration at the following intervals:

− Every 15 minutes of continuous operation

− when there is a change of set-up parameter, and/or of equipment (i.e. a change in probe)

− when the inspection is completed

− When the amplitude of the calibration signal has varied, re-calibrate the instrument and repeat

the inspection again at all locations from the last valid calibration

− Make sure the operational point is on the screen at all times.

Rebalance the instrument for each new scan path.

Do each scan of the inspection area at the same probe speed as used during the calibration

process.

Make sure the inspection surface is well illuminated.

A. Inspection Procedure

(1) After calibration, put the probe (coil) tip on the surface of the front lower spar directly

below the front spar web, outboard of the outer frame angle at BL 51.00.

Adjust the angle of the probe to ensure the blade is parallel to the inspection surface.

Refer to Figure 2 for inspection location and probe placement.

(2) Rebalance the instrument. If necessary, adjust the instrument [PHASE] control to obtain

a horizontal lift-off signal moving from right-to-left across the screen display.

(3) Make a linear horizontal scan of the front spar directly below the front spar web that is

covered by the inner and outer frame angles. Make sure the blade is parallel to the

inspection surface and the coil is in contact with the inspection surface at all times. The

inspection can be carried out from inboard and/or outboard of the frame angles

depending on operator preference. Refer to Figure 2 for inspection location and probe

placement.
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Page 10 of 23 ATA Ref: 57−10

6. Indication Evaluation

Any distinct vertical deflection signal that occurs over a short scan distance (one probe tip

diameter) is considered a suspect indication and is cause for further investigation.

Any rapid “up dot” movement signal that stays at the “up” position over a longer scan distance is

considered a suspect indication and is cause for further investigation.

Make sure the indication is not caused by edge effect, abrupt change in geometry, localized

variation in conductivity, permeability or other non-relevant factors.

Evaluate all suspect crack indications by comparing their phase angle, amplitude and shape to the

CRS EDM notch signals.

If a crack is detected, determine its length and determine its location.

7. Acceptance or Rejection Criteria

Any distinct vertical deflection signal, which equals to 50% or greater than the response from the

0.040-inch (1,02-millimeter) deep EDM notch as shown in Table 1 Calibration Data, is classified as

a crack and is cause for rejection.

8. Reporting

Record and report all rejections to your Bombardier Aerospace Specialized and Amphibious

Aircraft Technical Support Representative.

9. Close Out

If the finish on the inspection area was removed, replace the finish. Refer to the PSP 297,

Structural Repair Manual, Chapter 51−52−16, CORROSION PREVENTIVE TREATMENT −

GENERAL PROCEDURES.

Install access panels 310−1, 310−2, 721−3, and 821−3. Refer to the PSP 292, Aircraft

Maintenance Manual, Chapter 6−51−00, ACCESS PANELS DESCRIPTION AND OPERATIONS.

Remove all equipment, tools and unwanted materials from the work area.
MODEL CL-215-1A10

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April 5/13 Rev. NC Service Bulletin 215-A558

Page 11 of 23 ATA Ref: 57−10

10. PART C−2− EDDY CURRENT INSPECTION − WING LOWER REAR SPAR CAP

A. Preparation and Cleaning:

(1) Remove access panels 741−1, 841−2, 741−19, and 841−18. Refer to PSP 292, Chapter

6−51−00, ACCESS PANELS − DESCRIPTION AND OPERATIONS.

(2) Locate and identify all areas of the rear lower spar that require inspection. Refer to

Figure 3.

(3) This inspection must be performed from the rear side of the wing rear lower spar cap.

(4) Clean the areas to be tested thoroughly with aliphatic naphtha using a nylon bristled

brush and clean cloths. Allow the inspection surfaces to dry completely.

NOTE: If the paint or primer condition is good, it need not be removed. If the finish is

damaged, the bare metal must be exposed and refinished in accordance with

PSP 297, Structural Repair Manual, Chapter 51−52−16, CORROSION

PREVENTIVE TREATMENT − PROCEDURES.

11. Equipment Calibration for the Inspection of Surface Cracks in the Wing Lower Rear Spar Cap

A. Eddy Current Calibration Procedure

(1) Use a coaxial cable to connect the surface pencil probe to the Eddy Current instrument.

(2) Turn the instrument [ON]. Set and adjust the instrument controls as noted in TABLE 2

Calibration Data, Instrument Settings.

(3) Place the probe tip perpendicular to the surface of the CRS AL35−45 away from the

0.040−inch (1,02 millimeters) EDM notch and the edge. Refer to Figure 3.

NOTE: Avoid tilting the probe tip, this could result in a false indication.

(4) Balance (BAL) the instrument, and adjust the PHASE (ROTATION) control knob until a

horizontal lift−off signal moving from right to left is obtained with increasing lift−off across

the screen display.

(5) Slide the probe across the 0.040-inch (1,02 millimeters) deep EDM notch while

maintaining the probe perpendicular to the inspection surface at all times. Adjust the

instrument sensitivity [GAIN] to obtain an amplitude signal as shown in TABLE 2

Calibration Data, Instrument Settings.

(6) Differentiate between the edge and the notch signals by sliding the probe off the edge of

the reference standard. The signal obtained from the edge shall slant−off towards the

upper left quadrant as shown in TABLE 2 Calibration Data, Instrument Settings.

(7) If the inspection area is painted, carry out the lift−off compensation prior to inspection.

Refer to Step 11.B.
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B. Lift-Off Compensation Calibration

(1) After the calibration, put the probe (coil) tip perpendicular to the inspection surface. Do

not balance the instrument at this step.

(2) Compare the screen displays between the operating point on the inspection surface and

the balance point on the CRS.

(3) If the operating point on the inspection surface matches the balance point on the CRS, no

compensation for the paint thickness is required. Proceed to the inspection procedure.

(4) If the operating point on the inspection surface does not match the balance point on the

CRS, but has moved to the left on the display screen, compensation for the paint

thickness is required.

Do as follows:

(a) Attach a strip of nonconductive tape or shim to cover the CRS surface, including the

EDM notches.

(b) Put the probe (coil) tip perpendicular to the surface of the CRS, away from the EDM

notch and part edge. Rebalance the instrument and compare the operating point on

the inspection surface to the balance point on the CRS as shown on the instrument

display screen.

(c) If the operating point on the inspection surface is left of the balance point on the

CRS, add an additional strip of tape (thickness) or shim until the balance point on

the CRS matches that of the operating point of the inspection area.

(d) If the operating point on the inspection surface is to the right of the balance point on

the CRS with the tape applied, remove a strip of tape or shim until the balance point

on the CRS matches the operating point of the inspection area.

(e) If lift-off compensation and calibration requirements cannot be met, remove the paint

or other coatings from the inspection surface prior to the inspection.

Table 1

Calibration Data

LIFT−OFF SIGNAL BALANCE POINT

EDGE SIGNAL SIGNAL FROM 0.040 in (1,02 mm)

EDM NOTCH

80%

FSH

100%

0%

Mode ABS, Ch 1

Display XY

View Ch 1

Ch 1 Frequency 500 kHz

Ch 1 Phase 301.0

Ch 1 Gain 46 dB

Ch 1 X:Y X − 8 dB

Hi − Pass DC

Lo − Pass 200 Hz

Balance Load 47

X − Pos 40

Y − Pos −40

Table 2 − Calibration Data

Instrument Settings Screen Display

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(5) Slide the probe (coil) tip across the 0.040-inch (1,02-millimeters) deep EDM notch

covered with tape on the CRS.

(6) Adjust the [GAIN] to obtain an eddy current amplitude signal from the 0.040-inch

(1,02-millimeters) deep EDM notch as shown in Table 2 Calibration Data, screen display.

(7) Proceed to the inspection procedure.

12. Inspection of the Wing Lower Rear Spar Cap

NOTE: Monitor the test instrument screen display carefully at all times and make note of all

distinct, relevant indications: The screen amplitude of each signal and its relative location

on the inspection surface.

After the balancing in the inspection area, if the balance point drops below the screen display from

the original balance point, it could indicate the original balance location contains a defect. In such

a case, rebalance the instrument on an adjacent area and scan the original balance point for

possible defects before continuing the inspection.

Verify the instrument calibration at the following intervals:

− Every 15 minutes of continuous operation

− when there is a change of set-up parameter, and/or of equipment (i.e. a change in probe)

− when the inspection is completed

− When the amplitude of the calibration signal has varied, re-calibrate the instrument and repeat

the inspection again at all locations from the last valid calibration

− Make sure the operational point is on the screen at all times.

Rebalance the instrument for each new scan path.

Do each scan of the inspection area at the same probe speed as used during the calibration

process.

Make sure the inspection surface is well illuminated.

A. Inspection Procedures

(1) After calibration, put the probe (coil) tip on the surface of the rear lower spar directly

below the rear spar web, outboard of the outer frame angle at BL 51.00.

Adjust the angle of the probe to ensure the blade is parallel to the inspection surface.

Refer to Figure 3 for inspection location and probe placement.

(2) Rebalance the instrument. If necessary, adjust the instrument [PHASE] control to obtain

a horizontal lift-off signal moving from right-to-left across the screen display.

(3) Make a linear horizontal scan of the rear spar directly below the rear spar web that is

covered by the inner and outer frame angles. Make sure the blade is parallel to the

inspection surface and the coil is in contact with the inspection surface at all times. The

inspection can be carried out from inboard and/or outboard of the frame angles

depending on operator preference. Refer to Figure 3 for inspection location and probe

placement.
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13. Indication Evaluation

Any distinct vertical deflection signal that occurs over a short scan distance (one probe tip

diameter) is considered a suspect indication and is cause for further investigation.

Any rapid “up dot” movement signal that stays at the “up” position over a longer scan distance is

considered a suspect indication and is cause for further investigation.

Make sure the indication is not caused by edge effect, abrupt change in geometry, localized

variation in conductivity, permeability or other non-relevant factors.

Evaluate all suspect crack indications by comparing their phase angle, amplitude and shape to the

CRS EDM notch signals.

If a crack is detected, determine its length and determine its location.

14. Acceptance or Rejection Criteria

Any distinct vertical deflection signal, which equals to 50% or greater than the response from the

0.040-inch (1,02-millimeter) deep EDM notch as shown in Table 2 Calibration Data, is classified as

a crack and is cause for rejection.

15. Reporting

Record and report all rejections to your Bombardier Aerospace Specialized and Amphibious

Aircraft Technical Support Representative.

16. Close Out

If the finish on the inspection area was removed, replace the finish. Refer to the PSP 297,

Structural Repair Manual, Chapter 51−52−16, CORROSION PREVENTIVE TREATMENT −

GENERAL PROCEDURES.

Install access panels 741−1, 841−1, 741−19, and 841−18. Refer to the PSP 292, Aircraft

Maintenance Manual, Chapter 6−51−00, ACCESS PANELS − DESCRIPTION AND OPERATION.

Remove all equipment, tools and unwanted materials from the work area.

A. Recording

Upon completion of this Service Bulletin, record embodiment of this inspection in the aircraft

log book and return the attached Incorporation Notice to Bombardier Aerospace, Specialized

and Amphibious Aircraft, Customer Support.

17. Material Information

A. The following material, or equivalent, is required to embody this inspection and is to be

procured locally:

DESCRIPTION PART NO./NAME SPECIFICATION QUANTITY

Aliphatic Naphtha TT−N−95, Type ll A/R

Lint free cloth Commercially Available A/R

Non−Conductive tape Commercially Available A/R
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FIGURE 1

INSPECTION OF FRONT AND REAR SPAR CAP AREA FOR CRACKS

POSSIBLE

CRACK LOCATION

VIEW LOOKING UPWARD AND AFT

FROM LOWERSIDE OF THE WING AT FS 434.80

WING

LOWER SKIN

OUTBOARD

FRAME ANGLE

BL 51.00

SIDE PANEL
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FIGURE 2

INSPECTION OF THE WING FRONT LOWER SPAR AT BL51.00 AND FS388.86

FRONT SPAR

UPPER CAP (REF)

FRONT SPAR

WEB (REF)

OUTER FRAME ANGLE

(FRONT SPAR)

INSPECTION AREA

LBL

51.00

FS

388.86

VIEW ON FRONT SPAR LOOKING AFT

LEFT SIDE SHOWN, RIGHT SIDE OPPOSITE

INNER FRAME ANGLE

(FRONT SPAR)

FRONT SPAR

LOWER CAP
MODEL CL-215-1A10

MODEL CL-215-6B11

ALERT

SERVICE BULLETIN

April 5/13 Rev. NC Service Bulletin 215-A558

Page 17 of 23 ATA Ref: 57−10

FRONT SPAR WEB (REF)

FRONT SPAR

LOWER CAP

OUTBOARD FRAME ANGLE

FRAME ANGLE

FRONT SPAR (OUTBOARD)

STRAP (REF)

BOTTOM (REF)

WING SKIN

AIRCRAFT

FAIRING (REF)

FS

388.86

FIGURE 2

INSPECTION OF THE WING FRONT LOWER SPAR AT BL51.00 AND FS388.86

LINEAR SCAN

DIRECTLY BELOW THE

FRONT SPAR WEB
MODEL CL-215-1A10

MODEL CL-215-6B11

ALERT

SERVICE BULLETIN

April 5/13 Rev. NC Service Bulletin 215-A558

Page 18 of 23 ATA Ref: 57−10

FIGURE 2

CALIBRATION REFERENCE STANDARD AL 35−45

4

NOTES

1. Material: 2024−T62, QQ−A−250/4.

2. Finish surface 125 RMS or better.

3. Penetrant inspect as per BAPS 176−002.

 Identification sticker, 0.125 in (3.175 mm) letters black color.

5. Conductivity test as per BAPS 168−013.

6. EDM notches shall have a tolerance of 

for depth and +0.000/−0.002 in (+0.000/−0.051 mm) for width.

4

4

4

4

DEPTH

0.04 in

(1.02 mm)

DEPTH

0.02 in

(0.51 mm)

DEPTH

0.008 in

(0.20 mm)

1.00 in

(2.54 cm)

0.75 in

(19.05 mm)

0.75 in

(19.05 mm)

3.75 in

(9.53 cm)

1.50 in

(3.81 cm)

0.25 in

(6.35 mm)

0.005 in + 0.000/−0.002 in

(0.127 mm + 0.000/−0.051 mm)

WIDE x 1.50 in (38.10 mm)

LONG EDM NOTCH

(TYPICAL)

0.001 in (0,025 mm)
MODEL CL-215-1A10

MODEL CL-215-6B11

ALERT

SERVICE BULLETIN

April 5/13 Rev. NC Service Bulletin 215-A558

Page 19 of 23 ATA Ref: 57−10

FIGURE 2

OLYMPUS NDT FLEXIBLE BLADE PROBE

0.16 in.

(4,00 mm)

6.00 in.

(15,24 cm)

MICRODOT CONNECTOR

HANDLE

COIL

0.50 in.

(12,70 mm)

0.045−in

(1,14 mm)
MODEL CL-215-1A10

MODEL CL-215-6B11

ALERT

SERVICE BULLETIN

April 5/13 Rev. NC Service Bulletin 215-A558

Page 20 of 23 ATA Ref: 57−10

FIGURE 3

INSPECTION OF THE WING LOWER REAR SPAR AT BL51.00 AND FS434.83

REAR SPAR

UPPER CAP (REF)

REAR SPAR

WEB (REF)

REAR SPAR

LOWER CAP

RBL 51.00

INSPECTION AREA

OUTER FRAME ANGLE

(FRONT SPAR)

INNER FRAME ANGLE

(FRONT SPAR)

VIEW ON REAR SPAR LOOKING FWD

RIGHT SIDE SHOWN, LEFT SIDE OPPOSITE
MODEL CL-215-1A10

MODEL CL-215-6B11

ALERT

SERVICE BULLETIN

April 5/13 Rev. NC Service Bulletin 215-A558

Page 21 of 23 ATA Ref: 57−10

FIGURE 3

INSPECTION OF THE WING LOWER REAR SPAR AT BL51.00 AND FS434.83

STRAP (REF)

AIRCRAFT

FAIRING (REF)

FS

434.83

REAR SPAR WEB

(REF)

FRAME ANGLE

REAR SPAR

(OUTBOARD)

LINEAR SCAN

DIRECTLY BELOW THE

REAR SPAR WEB

REAR SPAR

LOWER CAP

WING SKIN

BOTTOM (REF)
MODEL CL-215-1A10

MODEL CL-215-6B11

ALERT

SERVICE BULLETIN

April 5/13 Rev. NC Service Bulletin 215-A558

Page 22 of 23 ATA Ref: 57−10

FIGURE 3

CALIBRATION REFERENCE STANDARD AL 35−45

4

NOTES

1. Material: 2024−T62, QQ−A−250/4.

2. Finish surface 125 RMS or better.

3. Penetrant inspect as per BAPS 176−002.

 Identification sticker, 0.125 in (3.175 mm) letters black color.

5. Conductivity test as per BAPS 168−013.

6. EDM notches shall have a tolerance of 

for depth and +0.000/−0.002 in (+0.000/−0.051 mm) for width.

4

4

4

4

DEPTH

0.04 in

(1.02 mm)

DEPTH

0.02 in

(0.51 mm)

DEPTH

0.008 in

(0.20 mm)

1.00 in

(2.54 cm)

0.75 in

(19.05 mm)

0.75 in

(19.05 mm)

3.75 in

(9.53 cm)

1.50 in

(3.81 cm)

0.25 in

(6.35 mm)

0.005 in + 0.000/−0.002 in

(0.127 mm + 0.000/−0.051 mm)

WIDE x 1.50 in (38.10 mm)

LONG EDM NOTCH

(TYPICAL)

0.001 in (0,025 mm)
MODEL CL-215-1A10

MODEL CL-215-6B11

ALERT

SERVICE BULLETIN

April 5/13 Rev. NC Service Bulletin 215-A558

Page 23 of 23 ATA Ref: 57−10

FIGURE 3

OLYMPUS NDT FLEXIBLE BLADE PROBE

0.16 in.

(4,00 mm)

6.00 in.

(15,24 cm)

MICRODOT CONNECTOR

HANDLE

COIL

0.50 in.

(12,70 mm)

0.045−in

(1,14 mm)
Upon completion of Service Bulletin(s), please fill in and return by fax to:

Service Bulletin Number(s) Rev.

Aircraft Serial No.

Date of Incorporation

Aircraft Reg. No.

Technical Publication,

Dept. 649-DBF−(9)

Bombardier Aerospace

Specialized &

Amphibious Aircraft

St. Laurent, Quebec

Fax No.: (514) 855−7602

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