ASB 206L-09-163A 

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ECCN EAR99 

 ALERT SERVICE BULLETIN 206L-09-163 

13 November 2009 

Revision A, 19 April 2012 

MODELS AFFECTED: 206L, 206L-1, 206L-3 and 206L-4 

SUBJECT: MAIN ROTOR BLADES P/N 206-015-001-115 

 /-117, /-119 & -121 SPAR SPACER, ONE 

 TIME INSPECTION OF. 

HELICOPTERS AFFECTED: Serial numbers 45004 through 45790, 46601 

through 46617, 51001 through 51612 and 52001 

through 52399 with the following main rotor 

blades installed: P/N 206-015-001-115 /-117 /-119 

and -121 with serial number A-XXXX, as listed in 

Table 1 or Table 2 of this bulletin. 

 [Serial number 52400 and subsequent will have the 

intent of this bulletin accomplished prior to delivery.] 

COMPLIANCE: PART I. Within the next 25 flight hours or 7 days, 

whichever comes first. Verify if your main rotor 

blade is listed in Table 1 or 2 of this bulletin. 

 PART II A and B. For main rotor blades listed in 

Table 1 or 2, at the next scheduled 100 flight hours 

inspection following the accomplishment of PART I 

of this bulletin.

PART III. Within the next 60 engine starts and every 

60 engine starts thereafter, for the main rotor blades 

listed in Table 2 of this bulletin that have oversized 

spar spacers installed as verified per the 

accomplishment of PART II B of this bulletin. This 

check shall be accomplished on blades that have 

accumulated more than 1200 flight hours and until 

the main rotor blade is removed from service or as 

instructed in PART IV of this bulletin. 
ASB 206L-09-163A 

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ECCN EAR99 

 PART IV. As an option to the Owners/Operators that 

have to accomplish PART III of this bulletin. 

After review of the spar radiographs by Bell 

Helicopter, a letter will be provided to the 

Owners/Operators indicating that the main rotor 

blade can remain in service with no further action 

required (terminating action with regards to PART III 

of this bulletin) or, that the blade can remain in 

service provided that PART III of this bulletin is 

accomplished until the main rotor blade reaches 

retirement life. 

DESCRIPTION: 

Bell Helicopter recently discovered that some P/N 206-015-001-115, /-117, /-119 and 

-121 main rotor blades have been manufactured with a spar spacer (aft spar closure) 

that was approximately 0.030 inch oversized. Upon analysis of this condition, Bell 

Helicopter is reducing the retirement life from 3600 to 2300 flight hours for the affected 

main rotor blades. 

The investigation has also established that a fatigue crack could occur if there was a 

combination of both oversized spar spacer and a larger than acceptable void in the 

adhesive applied between the blade's internal lead inertia weight and the spar, 

between blade stations 100 and 145. If such a condition exists, a fatigue crack may be 

induced by the centrifugal force variation that occurs during the helicopter start/stop 

cycles. 

Main rotor blades listed in Table 2 may have the described combination of both 

oversized spar spacers and a larger than acceptable adhesive void between the 

internal lead inertia weight and the blade spar. To be considered at risk of developing 

a crack, both conditions have to be met. Once the presence of an oversized spacer 

has been confirmed, an x-ray inspection of the spar can identify if an unacceptable 

void exists between the inertia weight and the spar. If, after accomplishment of PART 

IV of this bulletin, it is confirmed that no void exceeding the limitation is found, the 

blade is no longer considered at risk and no further accomplishment of PART III will be 

required. 

Revision A of this bulletin indicates June 30th 2012 as being the terminating date for all 

warranty considerations. Consequently, operators are not obliged to purchase a 

replacement blade or reach 2300hrs on re-identified blades to receive their 37% credit 

reimbursement. 

PART I of this bulletin has you verify if your main rotor blade is listed in Table 1 or 

Table 2 of this bulletin. For main rotor blades in spares stock, accomplish this 

verification upon receipt of this bulletin. 
ASB 206L-09-163A 

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ECCN EAR99 

PART II A of this bulletin provides you with instructions on how to measure the main 

rotor blades spar spacer. Blades with oversized spar spacers have to be re-identified 

and their retirement life reduced to 2300 flight hours. It is applicable to the main rotor 

blades listed in Table 1 of this bulletin. These main rotor blades have had PART IV of 

this bulletin accomplished prior to delivery. 

PART II B of this bulletin provides you with instructions on how to measure the main 

rotor blades spar spacer. Blades with oversized spar spacers have to be re-identified 

and their retirement life reduced to 2300 flight hours. In addition, for main rotor blades 

with more than 1200 flight hours, a main rotor blade spar wipe check is required every 

60 engine starts. It is applicable to the main rotor blades listed in Table 2 of this 

bulletin. These main rotor blades “DID NOT” have PART IV of this bulletin 

accomplished prior to delivery. 

Applicability of PART II A or B of this bulletin to any spare part shall be accomplished 

upon completion of PART I of this bulletin. 

-NOTEPART III affects only the blades listed in Table 2 with the 

oversized spar spacer as confirmed by PART II B of this 

bulletin. 

PART III of this bulletin introduces a recurring main rotor blade spar wipe check at 

every 60 engine starts for the main rotor blades that have oversized spar spacers 

installed as confirmed per the accomplishment of PART II B of this bulletin. This check 

is to be performed on main rotor blades that have accumulated more than 1200 flight 

hours. 

Applicability of PART III of this bulletin is for blades in service only. 

-NOTEPART IV is offered as an alternate option to the 

Owners/Operators with main rotor blades that are affected 

by the accomplishment of PART III of this bulletin. 

PART IV of this bulletin provides instructions on how to perform a one-time x-ray 

inspection. A radiographic picture of the main rotor blade spar is taken and then sent 

to Bell Helicopter for review. After review, depending on the results, Bell Helicopter will 

issue a letter that contains one of the following statements: 

a. The blade can remain in service with no further action required (terminating 

action with regards to the PART III of this bulletin). OR 
ASB 206L-09-163A 

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ECCN EAR99 

b. The blade can remain in service but PART III of this bulletin requires 

accomplishment until retired from service.

The radiograph must be taken by a Non-Destructive-Inspection (NDI) facility that has 

experience with accomplishing x-rays for the aerospace industry. The NDI facility shall 

also be capable of performing the work described in PART IV of the Accomplishment 

Instruction of this Alert Service Bulletin. Owners/Operators can contact their local Bell 

Helicopter Customer Service Facility (CSF), or refer to the Bell Helicopter Customer 

Support and Service Directory to locate the closest facility with x-ray capability in the 

CSF network, or a Bell Helicopter approved main rotor blade repair facility. 

In addition, a list of facilities with x-ray capabilities can be found in Table 5 of this 

bulletin. This list is not inclusive and is provided as a reference. The x-ray can be 

taken with either the blade installed or removed from the helicopter. 

Applicability of PART IV of this bulletin to any spare part is optional and shall be 

determined prior to its installation on an affected aircraft. 

APPROVAL: 

The engineering design aspects of this bulletin are Transport Canada Civil Aviation 

(TCCA) approved. 

CONTACT INFO: 

For any questions regarding this bulletin, please contact: 

Bell Helicopter Product Support Engineering - Light Helicopters 

Tel: 450-437-2862 / 1-800-363-8023 / pselight@bellhelicopter.textron.com 

MANPOWER: 

Approximately 0.5 man-hour is required to complete PART I of this bulletin. 

Approximately 2.5 man-hours are required to complete PART II A or B of this bulletin. 

Approximately 1.0 man-hour is required to complete PART III of this bulletin. 

Approximately 10 man-hours are required to complete PART IV of this bulletin. This 

estimate is based on hands-on time, and may vary with personnel and facilities 

available. 

WARRANTY: 

Owners / Operators of Bell Helicopters who comply with the instructions in this bulletin 

and find a cracked blade per PART III 5. and/or 6.b. will be eligible to receive a prorated credit for the replacement main rotor blade P/N 206-015-001-115/-117/-119/-121 

outlined under the Required Material section. 
ASB 206L-09-163A 

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ECCN EAR99 

In addition, Bell Helicopter will allow a credit reimbursement for x-rays described in 

PART IV of this bulletin together with freight costs up to a maximum of $1,000.00 per 

blade. To receive this credit you will be required to provide copies of the invoices for 

both the x-ray and freight costs to the warranty department. 

For blades that are identified to have a spar spacer that is larger than the dimensions 

described in PART II A & B of this bulletin, you will be able to receive a 37% credit for 

the unused 1,300 hours as a result of the reduction in life of the blade. Purchasing a 

replacement blade from a BHT supply source is not necessary to receive the credit. 

To receive either of the credits listed above: 

 Only those serial numbered blades that are listed in Table 2 of this bulletin 

are eligible for the x-ray and freight credit. 

 Comply with the instructions contained in the Compliance section of this 

bulletin. 

 Submit an MMIR to the Bell Warranty Department referencing this bulletin 

for the replacement part/x-ray & freight cost or for obtaining the 37% credit 

relative to the unused portion of 1,300hours. 

NOTE: Warranty compensations as stated above are no longer applicable after June 

30th 2012. No other labor cost will be covered under this bulletin. 

MATERIAL: 

Required Material: 

The following material is required for the accomplishment of this bulletin and may be 

obtained through your Bell Helicopter Textron Supply Center. 

Part Number Nomenclature Quantity Note

 

206-015-001-115 Main Rotor Blade 

(Standard white) 

A/R 1 

206-015-001-117 Main Rotor Blade 

(High visibility, 

black & white) 

A/R 1 

206-015-001-119 Main Rotor Blade 

(High visibility, 

orange & white) 

A/R 1 

206-015-001-121 Main Rotor Blade 

(All black) 

A/R 1 

NOTE: 

1. Required only if a main rotor blade spar is found cracked. 
ASB 206L-09-163A 

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ECCN EAR99 

Consumable Material: 

The following material is required to accomplish this bulletin, but may not require 

ordering, depending on the operator’s consumable material stock levels. This material 

may be obtained through your Bell Helicopter Textron Supply Center.

For PART II A and B of this bulletin 

Part Number Nomenclature Notes Quantity Reference

320 GRIT CLOTH 9X11 Abrasive Cloth, 320 grit 1 As required C-406

240 GRIT CLOTH 9X11 Abrasive Cloth, 240 grit 1 As required C-406

TT-N-95,TYII Aliphatic Naphtha 2 As required C-305

MIL-P-85582, TY1, CL2 Primer As required C-246

MIL-PRF85285 Paint 3 As required C-245

299-947-072 Fairing Compound 4 As required C-323

* C-XXX numbers refer to the consumables list in BHT-ALL-SPM Standard Practices Manual 

NOTES: 

1. Or equivalent Aluminum Oxide cloth 

2. As an alternate use Methyl Ethyl Ketone (C-309) or Acetone (C-316) 

3. Color code per FED-STD-595 as follows: 

a. Semi gloss white #27925 

b. Lusterless black #37038 

c. Gloss orange #12197 

d. Tip, orange yellow #33538 

4. Hysol EA 960 

For PART III of this Alert Service Bulletin 

Part Number Nomenclature Notes Quantity Reference

 

MILC87936TYI 5GAL Detergent 1 As required C-318

31-080AD002026 Decal 2 2 per blade N/A 

3950 SCOTCHCAL Decal Sealer 3 As required C-349

TT-I735 ISOPROPYL Isopropyl Alcohol As required C-385

N/A Blue Food Coloring 4 As required N/A

* C-XXX numbers refer to the consumables list in BHT-ALL-SPM Standard Practices Manual 

NOTES: 

1. Or equivalent aviation approved detergent. 

2. As an alternate, 0.25 inch X 2.50 inches red stripes can be painted. Color code 

#11136, FED-STD-595. 

3. Or equivalent sealer. 

4. Locally procured. 
ASB 206L-09-163A 

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ECCN EAR99 

SPECIAL TOOLS: 

None required. 

WEIGHT AND BALANCE: 

Not affected 

ELECTRICAL LOAD DATA: 

Not affected. 

REFERENCES: 

BHT-206L-MM-1 Chapter 65-00-00 

BHT-206L1-MM-1 Chapter 65-00-00 

BHT-206L3-MM-6 Chapter 62-00-00 

BHT-206L4-MM-6 Chapter 62-00-00 

Customer Support and Service Directory

PUBLICATIONS AFFECTED: 

BHT-206L-MM-1 Chapter 05-00-00 and Chapter 65-00-00 

BHT-206L1-MM-1 Chapter 05-00-00 and Chapter 65-00-00 

BHT-206L3-MM-1 Chapter 05-00-00 

BHT-206L3-MM-6 Chapter 62-00-00 

BHT-206L4-MM-1 Chapter 05-00-00 

BHT-206L4-MM-6 Chapter 62-00-00

ACCOMPLISHMENT INSTRUCTIONS: 

PART I. Verify if Your Main Rotor Blade is Affected 

1. Verify if your main rotor blade did or did not have PART IV of this bulletin 

accomplished prior to delivery as follows: 

a. Check if your main rotor blade S/N is listed in Table 1 and 2 of this bulletin. 

 
ASB 206L-09-163A 

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ECCN EAR99 

Table 1. List of Main Rotor Blades Serial Number (S/N) That Had PART IV of This 

Bulletin Accomplished Prior to Delivery

A-6710 A-6781 to A-6795 A-6877 

A-6713 A-6797 to A-6802 A-6883 to A-6885 

A-6717 & A-6718 A-6804 A-6887 

A-6722 to A-6725 A-6806 A-6889 to A-6895 

A-6736 & A-6737 A-6808 to A-6818 A-6897 to A-6902 

A-6740 to A-6744 A-6821 to A-6826 A-6906 to A-6910 

A-6747 & A-6748 A-6828 to A-6833 A-6912 & A-6913 

A-6750 to A-6758 A-6836 A-6916 

A-6760 to A-6769 A-6840 to A-6843 A-6919 to A-6921 

A-6771 to A-6775 A-6845 & A-6846 A-6923 & A-6924 

A-6777 A-6848 to A-6856 A-6927 & A-6928 

A-6779 A-6860 to A-6874 A-6958 

Table 2. List of Main Rotor Blades S/N That “DID NOT” Have PART IV of This 

Bulletin Accomplished Prior to Delivery

A-6027 A-6598 to A-6609 A-6693 to A-6698 

A-6208 A-6613 & A-6614 A-6704 to A-6706 

A-6547 A-6616 to A-6626 A-6708 & A-6709 

A-6549 & A-6550 A-6628 to A-6660 A-6711 & A-6712 

A-6555 A-6663 to A-6665 A-6715 

A-6560 to A-6563 A-6667 to A-6682 A-6726 to A-6728 

A-6565 A-6684 to A-6687 A-6734 & A-6735 

A-6567 to A-6596 A-6689 & A-6690 A-6738 

b. If your main rotor blade S/N is listed in Table 1, proceed with PART II A of this 

bulletin within the next scheduled 100 flight hour inspection. 

c. If your main rotor blade S/N is listed in the Table 2, accomplish PART II B of 

this bulletin within the next scheduled 100 flight hour inspection. 

2. If your main rotor blade S/N is not listed in either Table 1 or Table 2, no further 

action is required. Make required record entry indicating the finding to show that 

PART I of this bulletin is accomplished. 

PART II A. Main Rotor Blade Spar Spacer Measurement 

For main rotor blades that had PART IV of this bulletin accomplished prior to main 

rotor blade delivery as listed in Table 1. 
ASB 206L-09-163A 

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ECCN EAR99 

-NOTEAt the next scheduled 100 flight hour inspection following the 

accomplishment of PART I of this bulletin. 

1. Remove the tip weight support assembly (2) from the main rotor blade as follows: 

(Refer to Figure 1). 

a. Remove the four screws (1) holding the tip weight support assembly (2). 

b. Use a soft scraper and remove the filler around the tip weight support assembly 

(2). 

CAUTION 

When removing the tip weight support assembly (2) from the 

main rotor blade (5), be careful as washer (3) may have 

been installed between the main rotor blade spar (4) and the 

tip weight support assembly (2). Make sure you record the 

location of these washers (3) if installed. They are used to 

maintain the tip weight support assembly (2) contour 

alignment with the main rotor blade spar (4). 

c. Remove the tip weight support assembly (2) and record the location of the 

washer (3) if installed. 

2. Proceed with the measuring of the spar spacer (6) as follows: 

a. Use abrasive cloth grit 320 grit (C-406) or finer and sand just enough paint or 

primer to permit identification of the bond line between the main rotor blade 

spar (4) and spar spacer (6). 

b. Use a caliper and measure the main rotor blade spar spacer (6) tang width as 

shown on Figure 1. 

c. Record your dimension. 

3. Proceed with the installation of the tip weight support assembly on the main rotor 

blade as follows: 

a. Use a soft scraper and abrasive cloth 240 grit (C-406) and remove the 

remaining filler. 
ASB 206L-09-163A 

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ECCN EAR99 

b. Clean the sanded area around the main rotor blade spar (4) and spar spacer (6) 

with Aliphatic Naphtha (C-305) and touch-up the primer (C-246) and paint (C245) to make sure there is no bare metal exposed. 

c. Clean the mating faces on the main rotor blade (5) and the tip weight support 

assembly (2) with Aliphatic Naphtha (C-305). To maintain the tip weight support 

assembly (2) to main rotor blade contour, position the washers (3) if installed, in 

the location previously recorded and slip the tip weight support assembly (2) in 

the main rotor blade (5) recess. 

d. Install and torque the four screws (1) to 40 inch-pounds. (4.5 Nm) 

CAUTION 

Make sure you do not block the main rotor blade drain hole 

during the fill and fair process. 

e. Clean the main rotor blade (5) and tip weight support assembly (2) surrounding 

area mating line with Aliphatic Naphtha (C-305) and fill and fair the area using 

fairing compound (C-323). Use just enough fairing compound (C-323) to 

maintain the main rotor blade (5) contour. 

f. Touch-up the area with Primer (C-246) and paint (C-245) as required making 

sure there is no bare metal exposed. 

-NOTEOversized spar spacer (6) is approximately 0.030 inch 

(0.762 mm) larger than the maximum dimension limit of 

1.018 inch (25.86 mm) 

4. For main rotor blade with spar spacers (6) that are “WITHIN” spar spacer width. 

This maximum dimension shall not exceed 1.018 inch (25.86 mm), proceed as 

follows: 

a. Make required helicopter record entry indicating the finding and that PART II A 

of this bulletin is accomplished. No further action is required. 

5. For blades with main rotor blade spar spacers (6) that are “LARGER” than the 

maximum dimension of 1.018 inch (25.86 mm), proceed as follows: 

a. Use a vibrating tool and strike through the last three digits of the main rotor 

blade part number on the data plate. Re-identify main rotor blade data plate in 

accordance with the information provided in Table 3. The depth of the vibroetch 

must not exceed 0.005 inch (0.127 mm). 
ASB 206L-09-163A 

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ECCN EAR99 

Table 3. Main Rotor Blade Re-Identification Information

EXISTING PART NUMBER NEW PART NUMBER 

206-015-001-115 206-015-001-125 

206-015-001-117 206-015-001-127 

206-015-001-119 206-015-001-129 

206-015-001-121 206-015-001-131 

b. Make required record entry indicating that this specific main rotor blade 

retirement life is reduced from 3600 to 2300 flight hours. 

c. Make required helicopter record entry indicating that the PART II A of this 

bulletin is accomplished. No further action required. 

PART II B. Main Rotor Blade Spar Spacer Measurement 

For main rotor blades that did not have PART IV of this bulletin accomplished prior to 

main rotor blade delivery as listed in Table 2. 

-NOTEAt the next scheduled 100 flight hour inspection following the 

accomplishment of PART I of this bulletin. 

1. Remove the tip weight support assembly (2) from the main rotor blade (5) as 

follows: (Refer to Figure 1). 

a. Remove the four screws (1) holding the tip weight support assembly (2). 

b. Use a soft scraper and remove the filler around the tip weight support assembly 

(2). 

CAUTION 

When removing the tip weight support assembly (2) from the 

main rotor blade (5), be careful as washer (3) may have 

been installed between the main rotor blade spar (4) and the 

tip weight support assembly (2). Make sure you record the 

location of these washers (3) if installed. They are used to 

maintain the tip weight support assembly (2) contour 

alignment with the main rotor blade spar (4). 

c. Remove the tip weight support assembly (2) and record the location of the 

washer (3) if installed. 
ASB 206L-09-163A 

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ECCN EAR99 

2. Proceed with the measuring of the spar spacer (6) as follows: 

a. Use abrasive cloth grit 320 grit (C-406) or finer and sand just enough paint or 

primer to permit identification of the bond line between the main rotor blade 

spar (4) and spar spacer (6). 

b. Use a caliper and measure the main rotor blade spar spacer (6) width as shown 

on Figure 1. 

c. Record your dimension. 

3. Proceed with the installation of the tip weight support assembly (2) on the main 

rotor blade (5) as follows: 

a. Use a soft scraper and abrasive cloth 240 grit (C-406) to remove the remaining 

filler. 

b. Clean the sanded area around the main rotor blade spar (4) and spar spacer (6) 

with Aliphatic Naphtha (C-305) and touch-up the primer (C-246) and paint (C245) to make sure there is no bare metal exposed. 

c. Clean the mating faces on the main rotor blade (5) and the tip weight support 

assembly (2) with Aliphatic Naphtha (C-305). To maintain the tip weight support 

assembly (2) to main rotor blade spar (4) contour, position the washers (3) if 

installed, in the location previously recorded and slip the tip weight support 

assembly(2) in the main rotor blade (5) recess. 

d. Install and torque the four screws (1) to 40 inch-pounds. (4.5 Nm) 

CAUTION 

Make sure you do not block the main rotor blade drain hole 

during the fill and fair process. 

e. Clean the main rotor blade (5) and tip weight support assembly (2) surrounding 

area mating line with Aliphatic Naphtha (C-305) and fill and fair the area using 

fairing compound (C-323). Use just enough fairing compound (C-323) to 

maintain the main rotor blade (5) contour. 

f. Touch-up the area with Primer (C-246) and paint (C-245) as required making 

sure there is no bare metal exposed. 
ASB 206L-09-163A 

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ECCN EAR99 

-NOTEOversized spar spacer (6) is approximately 0.030 inch 

(0.762 mm) larger than the maximum dimension limit of 

1.018 inch (25.86 mm) 

4. For main rotor blade (5) with spar spacers (6) that are “WITHIN” spar spacer width. 

This maximum dimension shall not exceed 1.018 inch (25.86 mm), proceed as 

follows: 

a. Make required helicopter record entry indicating the finding and that PART II B 

of this bulletin is accomplished. No further action is required. 

5. For blades with main rotor blade spar spacers (6) that are “LARGER” than the 

maximum dimension of 1.018 inch (25.86 mm), proceed as follows: 

a. Use a vibrating tool and strike through the last three digits of the main rotor 

blade part number on the data plate. Re-identify main rotor blade data plate in 

accordance with the information provided in Table 4. The depth of the vibroetch 

must not exceed 0.005 inch (0.127 mm). 

Table 4. Main Rotor Blade Re-Identification Information

EXISTING PART NUMBER NEW PART NUMBER 

206-015-001-115 206-015-001-125 

206-015-001-117 206-015-001-127 

206-015-001-119 206-015-001-129 

206-015-001-121 206-015-001-131 

b. Make required record entry indicating that this specific main rotor blade 

retirement life is reduced from 3600 to 2300 flight hours. 

c. If the main rotor blade has presently accumulated more than 1200 flight hours 

or when the main rotor blade reaches 1200 flight hours, accomplish PART III of 

this bulletin within the next 60 engine starts and every 60 engine starts 

thereafter. PART IV of this bulletin offers an alternate option to the 

Owners/Operators that have to accomplish this check. 

d. Make required helicopter record entry indicating that the PART II B of this 

bulletin is accomplished. 

 
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ECCN EAR99 

-NOTEPART III and PART IV of this bulletin can be accomplished 

with the blade installed on the helicopter. 

PART III. Recurring Wipe Check Procedure. 

-NOTE- 

"Your National Airworthiness Authority (NAA) should be 

contacted to determine who can accomplish this main rotor 

blade wipe check, as it may be acceptable to be 

accomplished by a trained pilot or by trained maintenance 

personnel depending on the regulatory requirements of your 

NAA." 

1. Accomplish this recurring wipe check procedure every 60 engine starts as required 

per PART II B of this bulletin. This check shall be accomplished on blades that 

have accumulated more than 1200 flight hours until the main rotor blade is 

removed from service. PART IV of this bulletin offers a possible alternate option to 

the Owners/Operators that have to accomplish this check. 

2. In order to provide a quick visual reference, apply a “red stripe” decal (or paint if 

preferred) on both sides of the main rotor blade at the location indicated on Figure 

2. To prolong the life of the decal, apply Edge sealer (C-349) on the decal. 

Replace missing or damaged decal or re-apply paint as required. 

-NOTEThe marking of the spar at station 100 and 145 is required 

for accomplishment of PART III of this bulletin. For 

accomplishment of PART IV, the x-ray must be taken 

between stations 90 and 145 to ensure the complete section 

between stations 100 and 145 is captured. 

3. Mark the top surface of affected main rotor blade to identify station 100 and 145 as 

follows: 

a. The center of the blade bolt is blade station 18.5 (blade station zero being at the 

center of the mast). Use a permanent ink marker and make marks at blade 

stations 100 and 145. (Refer to Figure 2.) 

4. Proceed with the spar wipe check as follows: 
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ECCN EAR99 

a. Gain access to main rotor blades upper surface. 

b. Using detergent (C-318), thoroughly clean the main rotor blade upper surface 

between blade stations 100 to 145. Allow enough time for the blade upper 

surface to dry. 

c. Prepare blue food coloring solution that will be used to perform the check by 

thoroughly mixing the following in a clean container: 

 100 ml Isopropyl alcohol 99% (C-385) 

 100 ml clean tap water or distilled water 

 20 drops of blue food coloring 

d. Apply the blue food coloring solution in the area to be checked using 

cheesecloth (C-486) saturated with the solution or apply with a spray bottle. 

e. After 10 to 20 seconds, wipe off the solution with cheesecloth (C-486) in a span 

wise direction. 

f. Carefully check affected area for evidence of a crack. If a crack is present, the 

blue food coloring solution will remain in the crack as the excess of solution is 

wiped off and/or the cheesecloth will catch on the rough edges of the crack. 

5. If a crack is found, remove the main rotor blade from service before further flight 

and contact Bell Helicopter Product Support Engineering. 

-NOTEThe following inspection must be accomplished by a 

mechanic. 

6. If the blue food coloring solution wipe check as specified in step 4 above reveals a 

surface defect and the presence of a crack cannot be confirmed, perform the 

following inspection: 

a. With a 10X power magnifying glass examine the affected area for a crack. 

b. If a crack is found, remove the blade from service before further flight and 

contact Bell Helicopter Product Support Engineering. 

c. If no crack is found, repair the defect in accordance with the Component Repair 

& Overhaul manual. 

7. If no crack is found, make an entry in the helicopter technical records to show that 

PART III of this bulletin has been accomplished and indicate the findings. Repeat 
ASB 206L-09-163A 

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ECCN EAR99 

this check every 60 engine starts or as an option accomplish PART IV of this 

bulletin. 

Part IV. Main Rotor Blade Spar Radiography. (optional) 

Selection of an NDI facility 

1. The radiograph must be taken by a Non-Destructive-Inspection (NDI) facility that 

has experience with accomplishing x-rays for the aerospace industry. The NDI 

facility shall also be capable of performing the work described in PART IV of the 

Accomplishment Instruction of this bulletin. Owners/Operators can contact their 

local Bell Helicopter Customer Service Facility (CSF), or refer to the Bell Helicopter 

Customer Support and Service Directory to locate the closest facility with x-ray 

capability in the CSF network, or a Bell Helicopter approved main rotor blade repair 

facility. 

In addition, a list of facilities with x-ray capabilities can be found in Table 5 of this 

bulletin. This list is not inclusive and is provided as a reference. The x-ray can be 

taken with either the blade installed or removed from the helicopter. 

-NOTEUntil the radiographs are reviewed by Bell Helicopter and the 

disposition letter is received, affected blades can remain in 

service by complying with PART III of this bulletin. 

2. Advise the selected NDI Facility to contact Bell Helicopter Product Support 

Engineering (PSE) via e-mail at pselight@bellhelicopter.textron.com for shipping 

details of the radiographs. Bell Helicopter will perform the analysis and provide the 

main rotor blade disposition to both Owner and the NDI Facility. 

3. It is acceptable to have the radiographs taken with either the blade removed or 

installed on the helicopter. If the chosen NDI facility does not have the capability of 

performing PART IV with the blade installed on the helicopter, remove the blade 

using the applicable maintenance manual instructions and ship in a suitable 

container. 

4. Provide a copy of this bulletin to your NDI Facility for accomplishment of PART IV 

of this bulletin. 

 
ASB 206L-09-163A 

Page 17 of 26 

ECCN EAR99 

Radiography Procedure 

-NOTEThe following inspection procedure should only be used as a 

general guideline. The actual technique/procedure used 

shall be generated by the NDI Facility using technique 

parameters compatible with the equipment and processing 

chemistry utilized. Radiographs must be performed by 

individuals certified to a minimum of Level II in radiography 

per NAS410, CGSB-48.9712 (aerospace structures), or 

equivalent. 

1. Thoroughly clean blade with detergent (C-318). 

2. The radiograph of the spar is required between stations 90 and 145. Make sure the 

location is marked in accordance with PART III. 

3. Perform the blade spar radiograph as follows: 

General Guidelines 

Equipment 

 Fixed or portable x-ray generating system capable of producing x-rays of at 

least 75 kV and 5 mA energy and shall have a beryllium window. A focal spot 

no larger than 2.5 mm diameter is preferred for better results. Isotopes shall 

not be used.

 Either an automatic processor or hand development tank is an acceptable 

means of processing radiographs. Hand development shall be accomplished 

per the manufacturer’s instructions for type of film and chemicals used. 

 Film must be class I or II. 

Personnel

 Radiographs must be performed by individuals certified to a minimum of Level II 

in radiography per NAS410, CGBS-48.9712 (aerospace structures), or 

equivalent. 

Pre-Inspection

 Ensure cassettes and/ or rollpac films are in good condition and clear of any 

contaminants which may cause film artifacts. 

 Prior to film processing, solution concentration and radiographic exposure 

repeatability should be checked at least once each week using a step wedge or 

equivalent. 
ASB 206L-09-163A 

Page 18 of 26 

ECCN EAR99 

 The part shall be clean and free of loose debris. 

Inspection 

1. Blade removed from helicopter (Refer to applicable Maintenance Manual). 

a. Secure the blade to a stable platform such as sawhorses or blade dollies. 

-NOTEThe marking of the spar at station 100 and 145 is required 

for accomplishment of PART III of this bulletin. For 

accomplishment of PART IV, the radiography must be taken 

between stations 90 and 145 to ensure the complete section 

between stations 100 and 145 is captured. 

b. The blade shall be x-rayed at the bondline in the radius of the mid-span weight, 

(refer to Figures 3 and 4, from station 90 to station 145, (Refer to Figure 2). 

c. Blade stations can be located by placing a measuring tape at the center of the 

blade bolt hole. The center of the blade bolt is blade station 18.5 (blade station 

zero being at the center of the mast). The blade should have marks at stations 

100 and 145 previously made in PART III. (Refer to Figure 2). 

d. Lead markers shall be placed on the blade to provide evidence of complete 

coverage and sufficient overlap. The film shall also contain lead numbers 

indicating blade P/N, S/N and station locations 90 and 145 as a minimum. 

e. Align the x-ray beam perpendicular to the blade lower surface and center the 

beam 0.8 inch from the leading edge, (Refer to Figures 3 and 4). 

f. Process the films and return them to Bell Helicopter for review. 

2. Blade installed on helicopter. 

a. Rotate the blades perpendicular to the tailboom. (Refer to Figure 3). 

b. Stabilize the main rotor blades to prevent movement and film distortion. 

c. Due to the static droop and pitch angle of the blades, care must be taken to 

ensure the center of the x-ray beam stays perpendicular to the bond line, (Refer 

to Figure 3). 

d. Inspect affected blade per above step 1.b. to 1.f. 

 
ASB 206L-09-163A 

Page 19 of 26 

ECCN EAR99 

Recommended Technique

KV** 75 

Ma 4.5 

Time 2.0 Min 

SFD Min 36” 

Density Range* 1.5 to 3.5 

Film Agfa D4 

* Density should be measured on the leading edge adjacent to the bond line. 

* Energy settings, film, and time are to be used as a reference only. 

**. Actual exposure technique should be based on energy levels capable of exposing 

0.8 inch – 0.9 inch of aluminum to a density of 2.0. 

3. Prepare the radiographs for shipping and include blade part and serial numbers 

with the total time in service. 

4. Contact Bell Helicopter Product Support Engineering (PSE) via e-mail at 

pselight@bellhelicopter.textron.com for radiograph shipping instructions. When 

contacting PSE, clearly specify that the radiographs are being sent for 

accomplishment of ASB 206L-09-163A and make sure to provide the following 

detailed information for both the NDI Facility and blade owner in order for Bell 

Helicopter to provide inspection results in a timely manner: 

 Company name 

 Contact name 

 Phone number 

 E-mail address 

5. Bell Helicopter will analyze the content of the radiographs and provide a letter 

indicating one of the following: 

a. The blade can remain in service with no further action required (terminating 

action with regards to the PART III of this bulletin). OR 

b. The blade can remain in service but PART III of this bulletin requires 

accomplishment until retirement from service. 

6. Make an entry in the helicopter technical records to show that the PART IV of this 

bulletin has been accomplished indicating the blade disposition based on the letter 

received by Bell Helicopter. 

 
ASB 206L-09-163A 

Page 20 of 26 

ECCN EAR99 

TABLE 5. List of NDI Facilities 

Aviation NDT Services, PTY Ltd. 

Store 7, Gate 24 Operations Road 

Melbourne Airport 

Victoria, Australia 3045 

Phone: 61-3-9395-0632 

Australia Central Flying Service Inc. 

12th and Calhoun 

Little Rock, AR 72202 USA 

Phone: 1-800-844-6257 

USA 

Qantas Airways, Nondestructive Tests 

Section 

M96/1 Mascot Maintenance Base 

Sydney, New South Wales Australia 

2020 

Phone: 612-9691-7402 

Australia CTC (Certified Testing & Consulting 

Services), LLC 

3144 Venture Drive, Suite #100 

Lincoln, CA 95648 USA 

Phone: 1-916-434-0195 

USA 

Sabena Technics Nondestructive 

Inspection Dept. 

Brussels National Airport, Hanger #8, 

Door #5 Zaventem, Brussels, Belgium 

B1930 

Phone: 3212-53-55 

Belgium Certified Inspection Services, LLC 

3755 Industrial Court, NW, Suite 

#16 

Suwanee, GA 30024 USA 

Phone: 1-678-730-2000 

USA 

CAL – Compoende Aeronautica Ltda 

Av. Dos Ipes, 391 

Flor do Vale, Tremembe-Sao Paulo 

12120-000 Brazil 

Phone: 55-12-3672-1911 

Brazil E & I Aircraft 

5525 N. W. 23rd Avenue 

Ft Lauderdale Executive Airport 

Hangar #17 

Fort Lauderdale, FL 33309 USA 

Phone: 1-954-771-9194 

USA 

Cantech Aviation Inspections Ltd 

120-13451 Vulcan Way 

Richmond, British Columbia V6V 1K4 

Canada 

Phone: 1-604-244-9699 

Canada EPPS Aviation Inc. 

1 Aviation Way 

Atlanta, GA 30341 USA 

Phone: 1-770-458-9851 

USA 

Execaire, a Division of I.M.P. Group 

Limited, 2450 Derry Road East, HGR7 

Mississauga, Ontario Canada L5S 1B2 

Phone: 1-905-677-2484 

Canada ETI Ewer Testing & Inspection Inc. 

1131 South 22nd Street 

Bismarck, ND 58504 USA 

Phone: 1-701-223-6434 

USA 

Execaire, a Division of I.M.P. Group 

Limited, 10225 Ryan Avenue, 

Dorval, Quebec H9P 1A2 Canada 

Phone : 1-514-636-7070 

Canada Flight Craft 

7505 N.E. Airport Way 

Portland Oregon 97218 USA 

Phone: 1-503-331-4219 

USA 

Perimeter Aviation 

626 Ferry Road 

Winnipeg, Manitoba Canada R3H 0T7 

Canada Flight Options LLC 26180 Curtis 

Wright Parkway 

Richmond Heights, OH 44143 USA 

Phone: 1-216-797-8473 

USA 

RTD Quality Services Inc. 

2280 Pegasus Way N.E. #8 

Calgary, Alberta T2E 8M5 Canada 

Phone: 1-403-274-8214 

Canada General Dynamics Aviation Services 

W6365 Discovery Drive 

Appleton, WI 54915 USA 

Phone: 1-920-735-7028 

USA 

Hainan Airlines Co. Ltd./FIC-CAAC NDT 

Office 

16# No. 1Street 

Fugian, Beijing, China 100621 

Phone: 8-610-645-85945 

China General Dynamics Aviation Services 

5616 Haven Street 

Las Vegas, NV 89119 USA 

Phone: 1-702-947-3030 

USA 
ASB 206L-09-163A 

Page 21 of 26 

ECCN EAR99 

Aerospace NDT Ltd. Suite A, Bldg 

#6, Fourth Ave. 

Doncaster, South Yorkshire 

England DN9 3GE 

Phone: 44-1302-770771 

England General Dynamics Aviation Services 

6925 34th Ave. south 

Minneapolis, MN 55450 USA 

Phone: 1-612-638-2053

USA 

Morgan-Ward (NDT) ltd. 

Dale Road 

New Mills, High Peak, Derbyshire 

England Sk22 4NW 

Phone: 44 (0) 1663-74-7061 

England General Electric Inspection Services 

1211 Kona Drive 

Rancho Dominguez, CA 90220 USA 

Phone: 1-310-635-2700 

USA 

GIE – NDT Expert 

Sciences Parc du Perget 31770 

Colomiers, France 

Phone : 33-53436-1200 

France General Electric Inspection Services 

5425 Business Parkway 

Theodore, AL 36582 USA 

Phone: 1-251-653-6060 

USA 

Aircraft Services Lemwerder (ASL) 

Flughafenstrabe 5 

Lemwerder, 27809 Germany 

Phone: 49-421-672-2279 

Germany JETS Inc. 

1325 Whitlock Lane 

Carrollton, TX 75006 USA 

Phone: 1-972-323-6808 

USA 

RUAG Aerospace Services GmbH 

Flugplatz Oberpfaffenhofen Geb. 379 

P.O. Box 1253 

Wessling, Bayern D-82234 Germany 

Phone: 49-815-330-2897 

Germany Metal Finishing Company 

1329 South McLean Blvd 

Wichita, KS 67213 USA 

Phone: 1-316-267-7289 

USA 

Airworks India Engineering Pvt. Ltd 

Gate 8, Mumbai Old Airport 

Kalina, Santa Cruz (E) Mumbai, 

Maharashrta, India 400029 

Phone : 91-22-2615-7213 

India MidCoast Aviation, Inc. 

6400 Curtis-Steinberg Drive 

Cahokia, IL 62206 USA 

Phone: 1-618-337-2100/Ext. 6351 

USA 

Air Four S.p.A. 

Viale Dell Aviazione 65 

Milano, Italy 20138 

Phone: 00-39-02-50673-404 

Italy NDE Services Inc. 

15552 E. Fremont Drive, Unit A106 

Centennial, CO USA 80112 

Phone: 1-303-741-0518 

USA 

CND Services (Controlli Non Distruttivi) 

SRL Via A. Flores, 

17 Localita Monna Felicita (Zona 

Industriale 

Civitavecchia (RM) Italy 00053 

Phone : 0039-766-580521 

Italy NDT Inspect-Air Inc. 

4557 96th Street 

Franksville, WI USA 53126 

Phone: 1-262-878-8700 

USA 

Nippi Corporation/Japan Aerospace 

Aircraft NDT Department 2-28 

Soyagi, Yamamoto, Kanagawa, 242-

0026 Japan 

Phone: 046-265-2082 

Japan Paragon Services, Inc. 

1015 South West Street 

Whichita, KS 67213-1627 USA 

Phone: 1-316-945-5285 

USA 

Korean Air 

1370 Gonghang-Dong 

Gangseo-Gu, Seoul, 157-712, Korea 

Phone: 82-2-660-7486 or 82-2-656-

7480 

Korea Power Aviation Inc. 

1255 Laquinta Drive Suite 112 

Orlando, FL 32809 USA 

Phone : 1-407-438-1395 

USA 
ASB 206L-09-163A 

Page 22 of 26 

ECCN EAR99 

Unit Inspection Aviation S.A. 

Hanger Z3 Lanseria International 

Airport 

Lanseria South Africa 1748 

South Africa 

Phone: 11-27-701-3058 

South 

Africa 

 Q.C. Laboratories Inc. 

2870 Stirling Road 

Hollywood, FL 33020 USA 

Phone: 1-954-925-0499 

USA 

FORCE Technology Sweden AB 

August Barks Gata 23B 

Vastra Frolunda, Goetborg, Sweden 

42132 

Phone: 046-031-490210 

Sweden Quality Testing Services, Inc. 

2305 Millpark Drive 

Maryland Heights, MO 63043 USA 

Phone: 1-314-770-0607 

USA 

SR Technics, TEQN 

Zurich Airport 

Zurich, ZH-8058 Switzerland 

Phone: 41-1-812752 

Switzerla

nd 

 St. Louis Testing Laboratories Inc. 

2810 Clark Avenue 

St. Louis, MO 63103 USA 

Phone: 1-314-531-8080 or 1-800-

264-1120 

USA 

CSE Citation Centre – UK 

Bournemouth IAP, Hanger #100 

Christchurch, Dorset, UK BH23 6NW 

Phone: 44-0120-285-7759 

United 

Kingdom 

 Standard Aero (formerly Landmark 

Garrett Aviation Services) 

1550 Hanger Road 

Augusta, GA 30906 USA 

Phone: 1-800-891-8889 

USA 

FR Aviation (formerly Flight Refueling 

Ltd.) Bournemouth International 

Airport 

Christchurch, Dorset BH23 6NE UK 

Phone: 1-44-01202-409000 

United 

Kingdom 

 Standard Aero (formerly Landmark 

Garrett Aviation Services) 

Springfield, Illinois 62707 USA 

Phone: 1-217-535-3596 

USA 

Marshall of Cambridge Aerospace Ltd 

Cambridge Airport, Cambridge UK CB5 

8RX 

Phone: 44 (0) 1223-373216 

United 

Kingdom 

 Standard Aero (formerly Landmark 

Garrett Aviation Services) 

George Bush Int. Airport (IAH) 

17250 Chanute Road 

Houston, TX USA 

Phone: 1-281-233-4150 

USA 

Material Measurements Ltd 

61 Albert Road North 

Reigate, Surrey UK RH2 9RS 

Phone: +44 (0) 1737-222211 

United 

Kingdom 

 Standard Aero (formerly Landmark 

Garrett Aviation Services) 

6201 West Imperial Highway 

Los Angeles, CA USA 

Phone: 1-310-568-3825 

USA 

Acuren Inspection Inc. 

3101, 111th St. SW, Unit “C” 

Everett, WA 98204 USA 

Phone: 1-425-355-5019 

USA StarPort Cambata Aviation, Int. LLC 

100 Starport Way 

Sanford, FL 32773 USA 

Phone: 1-407-321-8880 

USA 

Acuren – US Inspection Inc. 

1485 Corporate Woods Parkway 

Union Town, OH 44685 USA 

Phone: 1-330-899-0566 

USA Stork Twin City Testing Corporation 

662 Cromwell Ave. 

St. Paul, MN 55114 USA 

Phone: 1-651-659-7440 

USA 

Aircraft NDT Service Inc. 

6395 Technology Ave. Suite “C” 

Kalamazoo, MI 49009 USA 

Phone: 1-616-353-3658 

USA Structural Testing Systems 

97 Hering Drive L. I. MacArthur 

Airport 

Ronkonkoma, NY 11779 USA 

Phone: 1-516-981-0242 

USA 
ASB 206L-09-163A 

Page 23 of 26 

ECCN EAR99 

All American Inspections 

106 E. Turbo 

San Antonio, TX 78216 USA 

Phone: 1-210-525-0421 

USA Tailwind Inspection, Inc. 

3260 N Sheridan Road 

Tulsa, OK 74115 USA 

Phone: 1-918-832-0700 

USA 

Apex Inspections 

2530 Tarpley Suite #200 

Carrollton, TX 75006 USA 

Phone 1-972-418-5672 

USA Tailwind Inspection, Inc. 

70 – C King Spring Road 

Windsor Locks, CT 06096 USA 

Phone: 1-860-623-8600 

USA 

Applied Technical Services Inc. 

1190 Atlanta Industrial Drive 

Marietta, GA 30066 USA 

Phone: 1-770-423-1400 

USA Tailwind Inspection, Inc. 

7515 Lemmon Ave. 

Dallas, TX 75209 USA 

Phone: 1-214-357-9595 

USA 

Applied Technical Services Inc. 

214 Pelham Davis Circle 

Greenville, SC 29615 USA 

Phone: 1-864-675-6060 

USA The Aerospace NDT Company Inc. 

(formerly Rogers NDT) 

3418 Cypresswood Dr. 

Spring, TX 77388 USA 

Phone: 1-281-482-0228 

USA 

Applied Technical Services Inc. 

1325 “B” Cavalier Blvd 

Chesapeake, VA 23323 USA 

Phone: 1-757-558-0016 

USA THI (The Hangar Inc.) 

2930 Winchester Road, Suite 500 

Memphis, TN 38118 USA 

Phone: 1-901-345-8885 

USA 

Canyon State Inspection 

3625 East Ajo Way 

Tucson, AZ 85713 USA 

Phone: 1-520-745-3672 

USA Aerocentro De Servicios C.A. 

Aeropuerto Caracas-Edifico 

Aerocentro. Charallavre, Mirauda VZ 

Post Code 1210 

Phone : 1-561-317-8848 

Venezuela 

Canyon State Inspection 

103 South Southgate 

Chandler, AZ 85226 USA 

Phone: 1-480-783-7183 

USA Airtech Servicios Aereos, C.A. 

Aeropuerto Caracas 

Oscar Machado Zuloaga Edif. 

Airtech 

Charallave, Miranda 4383 

Venezuela (VE) 

Phone: 58-14-939-1949 

Venezuela 
ASB 206L-09-163A 

Page 24 of 26 

ECCN EAR99 

FIGURE 1. Main Rotor Blade Spar Spacer Inspection 
ASB 206L-09-163A 

Page 25 of 26 

ECCN EAR99 

FIGURE 2. Main Rotor Blade Area to be Checked 

FIGURE 3. Radiograph with Blades Installed 
ASB 206L-09-163A 

Page 26 of 26 

ECCN EAR99 

FIGURE 4. Cross Section of Main Rotor Blade