# .**~111111111111111.** 

# I

DATE REV



### MODEL AFFECTED: SUBJECT: 

### ALERT SERVICE BULLETIN

# ~~ Bell ellcopt r No. 

### 206L-06-140 A Subsidiary of Textron Inc. DATE 

### SEP 7, 2006**~** PAGE 1 of6**~** 

### 206L, L-1, L-3 and L-4 UPPER LEFT HAND TAILBOOM ATTACHMENT HARDWARE, INSPECTION OF HELICOPTERS AFFECTED: Model 206L helicopters all serial numbers, 206L1 all serial numbers, 206L3 all serial numbers and 206L4 serial number 52001 through 52185 that had a 407- 030-750-103 upper left-hand CRES steel fitting field retrofitted.



### COMPLIANCE:

DESCRIPTION: Model 206L-4 helicopters serial number 52186 through 52324 . [Model 206L-4 helicopters serial numbers 52325 and subsequent will have the intent of this bulletin accomplished prior to delivery.] PART I Within the next 50 hours after receipt of this bulletin. PART II At the next scheduled 100 Hrs/annual inspection, after Part I has been accomplished .

Bell Helicopter found that on some helicopters having the 407-030-750-103 CRES steel fitting installed at the upper left-hand location, the attachment bolt might not meet the installation requirement. PART I of this bulletin provides instructions to verify if a CRES steel fitting is installed at the upper left-hand location and check for the amount of bolt threads exposed .ASB 206L-06-140 Page 2 of 6 PART II of this bulletin provides instructions to replace the upper left-hand bolt if required , as indicated in PART I. APPROVAL: The engineering design aspects of this bulletin are Transport Canada approved. MANPOWER: Approximately 0.5 man-hour is required to perform PART I and 1 man-hour to perform PART II of this bulletin. Man-hours are based on hands-on time, and may vary with personnel and facilities available. WARRANTY: Warranty does not apply for parts or labor associated with 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 20-065-06026 Nomenclature Bolt Note: The bolt may not require replacement. Refer to PART I. SPECIAL TOOLS: None required WEIGHT AND BALANCE: Not Affected Quantity 1

### ELECTRICAL LOAD DATA: Not affected 

### REFERENCES : BHT-206L-MM, Maintenance Manual BHT-206L1-MM, Maintenance Manual BHT-206L3-MM, Maintenance Manual BHT-206L4-MM , Maintenance Manual 

### PUBLICATIONS AFFECTED: BHT-206L-MM , Maintenance Manual BHT-206L1-MM , Maintenance Manual BHT-206L3-MM , Maintenance Manual BHT-206L4-MM , Maintenance Manual BHT-206L-SERIES-IPB, Illustrated Parts Breakdown 

### ACCOMPLISHMENT INSTRUCTIONS: PART I. Left-hand upper fitting and bolt inspection. ASB 206L-06-140 Page 3 of 6

1 . Remove the tailboom attachment access door from right side offuselage forward of tailboom bulkhead . Refer to the applicable Maintenance Manual , chapter 53. 2. Gain access to upper left-hand tailboom fitting (7, Figure 1).-NOTEHelicopters 206L4 S/N 52186 through subsequent were delivered with corrosion resistant steel (CRES) fitting 407-030-750-103 installed. 3. For helicopters 206L, L1, L3 all serial numbers and L4 s/n 52001 through 52185 , verify if CRES steel fitting is installed. Those aircrafts were originally delivered with aluminum fitting that may have been replaced by the CRES fitting and longeron assembly 206-031-314-157A. CRES steel fitting (7) may be identified as follows :ASB 206L-06-140 Page 4 of 6
a. The part number 407-030-750-103 maybe stamped on the fitting . b. The longeron and the aluminum fitting were replaced by longeron assembly 206-031-314-157

### A. c. The CRES fitting 407-030-750-1 03 is composite bonded to the longeron and the bonding layer might be visible . d. The CRES fitting 407-030-750-103 is ferrous and can be identified using a magnet. 4. If the helicopter does not have a CRES fitting installed, no further action is required. Make an entry in the helicopter records to indicate that this bulletin has been accomplished. 5. For helicopters affected by this bulletin that have a CRES fitting installed , perform thread count on the upper left hand attachment bolt (1) as per Figure 1. 6. If the correct amount of thread is exposed (between 1 and 3), do a torque check. Refer to the Maintenance Manual. If the torque is correct, make an entry in the helicopter records to indicate that this bulletin has been accomplished. If the torque is found below minimum and a replacement bolt (1) is not available at this time, adjust the washer (3) quantity as required per Figure 1. Refer to the Maintenance Manual and torque as required. Make an entry in the helicopter records to indicate that the PART I of this bulletin have been accomplished and that the PART II of this bulletin will require accomplishment. 7. If less than 1 thread is exposed, adjust the washer (3) quantity as required per Figure 1. Refer to the Maintenance Manual and torque as required. Make an entry in the helicopter records to indicate that this bulletin has been accomplished. 8. If more than 3 threads are exposed and a replacement bolt (1) is not available at this time, adjust the washer (3) quantity as required per Figure 1. Refer to the Maintenance Manual and torque as required . Make an entry in the helicopter records to indicate that the PART I of this bulletin have been accomplished and that the PART II of this bulletin will require accomplishment. 9. If more than 3 threads are exposed and a replacement bolt (1) is available, accomplish Part II of this bulletin .

### ASB 206L-06-140 Page 5 of 6 PART II. Upper left hand tailboom attachment bolt replacement. 1. Remove and discard the upper left hand tailboom attachment bolt (1, Figure 1). Install new bolt (1) and adjust the quantity of washer (3) as required to ensure correct installation as shown on Figure 1. If serviceable, the nut (4) does not require replacement. Refer to Maintenance Manual. 2. 100 hours after installation , do a torque check of the upper left hand tailboom attaching hardware . Refer to the applicable Maintenance Manual. 3. Make an entry in the helicopter records to indicate that this bulletin has been accomplished.ASB 206L-06-140 Page 6 of 6

From the end ofthe bolt, a complete thread count starts on the back face ofthe first thread groove and moves axially to the adjacent groove. Three threads shown . 1 . Bolt 2. Washer, chamfered under bolt head 3. Washer, as required 4. Nut 5. Tailboom 6. AFT fuselage 7. Fitting NOTES 

# ffi Bolt (1) and chamfered washer (2) are to be installed through tailboom (5) and Aft fuselage (6). Bolthead and chamfered washe r are to be installed on the tailboom side. Steel washe rs (3) are to be installed next to fitting (7) to provide not less than one thread and not more than th ree th reads exposed on threaded end of bolt (1). 

# £ If thread count is less than one, remove washers as req uired . 

# & Ifthread count is more than three, remove and replace bolt, then readjust number of washers to meet requirement of note 1 . RAM_06541_001 Figure 1: Tailboom Attachment