DATE 

ALERT SERVICE BULLETIN 

REVISION NOTICE 

AN APPROPRIATE ENTRY SHOULD BE MADE IN THE AIRCRAFT LOGBOOK UPON ACCOMPLISHMENT 

IF OWNERSHIP OF AIRCRAFT HAS CHANGED PLEASE FORWARD TO NEW OWNER

Jan 11,2011 

TO: All Owners/Operators of Bell 205B Helicopters

SUBJECT: REVISION “B” TO ALERT SERVICE BULLETIN 205B-08-51: 

 MAIN ROTOR BLADE P/N 212-015-501-005, -111, -113, -115, -117, -119 

AND, -121; INSPECTION OF. 

Revision “A” to this bulletin is being issued for an editorial change in the 

“DESCRIPTION” paragraph. 

Revision “B” to this bulletin is being issued to change the inspection interval and 

procedure. Changes were made to the following paragraphs: “HELICOPTERS 

AFFECTED”, “COMPLIANCE” and “ACCOMPLISHMENT INSTRUCTIONS”. 
NO. 

 

DATE 

PAGE 

 DATE 

 REV 

ALERT SERVICE BULLETIN 

AN APPROPRIATE ENTRY SHOULD BE MADE IN THE AIRCRAFT LOGBOOK UPON ACCOMPLISHMENT 

IF OWNERSHIP OF AIRCRAFT HAS CHANGED PLEASE FORWARD TO NEW OWNER

205B-08-51 

01/11/2011 Dec 19, 2008 

B 1 of 6 

MODEL AFFECTED: 205B

SUBJECT: MAIN ROTOR BLADE P/N 212-015-501-005, -111, 

-113, -115, -117, -119 and, -121, INSPECTION OF. 

HELICOPTERS AFFECTED: Model 205B helicopters serial number 30188, 

30166, 30066 and, 30297. 

 

 

COMPLIANCE: Within the next 25 hours after receipt of this bulletin 

and every 25 hours of operation thereafter.

DESCRIPTION: 

 

A model 212 Main Rotor Blade P/N 212-015-501-115 with approximately 1000 hours 

total time was recently returned to BHTI for evaluation. The blade was found cracked 

through the blade retention bolt hole at Blade Station 28.0 and another crack through 

the lower grip plate at Blade Station 36.0. The main rotor blade contained a fatigue 

fractured grip plate, fatigue fractured doublers and a fatigue cracked spar on the 

bottom of the blade as a result of inadequate bond between the doublers and grip 

plate. Further analysis and investigation of two more blades with similar conditions 

required the introduction of a recurring inspection of the Main Rotor Blade every 25 

hours of operation. Refer to Figure 1 for the inspection area and Figure 2 showing 

typical cracks. 

APPROVAL: 

The engineering design aspects of this bulletin are FAA/ODA approved. 

MANPOWER: 

Approximately 1.0 man-hour is required to comply with this bulletin. Man-hours are 

based on hands-on time, and may vary with personnel and facilities available. 

B

B
ASB 205B-08-51 

Page 2 of 6 

WARRANTY: 

There is no warranty provided for this bulletin. 

MATERIAL: 

Required Material: 

None required 

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 the Bell Helicopter Textron Supply Centers.

Part Number Nomenclature Quantity Reference

 

MILC87936TY1 Cleaning Compound 1 liter C-318 

WD-40 

TT-I735 ISOPROPYL 

Preservative Oil 

Isopropyl Alcohol 

12 OZ 

1 GAL 

C-125 

C-385 

 

SPECIAL TOOLS: 

None required 

WEIGHT AND BALANCE: 

Not affected 

ELECTRICAL LOAD DATA: 

Not affected 

REFERENCES: 

BHT-212-IPB Illustrated Parts Breakdown 

BHT-212-MM Maintenance Manual 

BHT-212-CR&O Component Repair and Overhaul Manual 

BB
ASB 205B-08-51 

Page 3 of 6 

PUBLICATIONS AFFECTED: 

BHT-212-MM Maintenance Manual 

ACCOMPLISHMENT INSTRUCTIONS: 

1. Wash upper and lower Main Rotor Blade surfaces with a solution of cleaning 

compound (C-318) and water. Rinse thoroughly and wipe dry. 

-NOTEAccomplishment of this inspection does not require removal 

of the blades from the Main Rotor Hub. 

2. Inspect the Main Rotor Blade upper and lower grip plates and doublers for their 

entire length and chord width. Inspect for signs of cracks, corrosion and edge 

voids, paying particular attention to the bond lines between doublers, grip plates 

and skin. Hair line cracks in the paint finish should be suspect for possible cracks / 

voids. 

3. Wipe the area to be inspected with an alcohol-soaked cloth (C-385) and wipe dry 

with a clean cloth. 

-NOTEAccomplish Step 4 of this ASB immediately after carrying out 

the above alcohol wipe. Any potential cracks in the bond 

lines between doublers or grip plates will be indicated by the 

presence of excess alcohol bleeding out of an edge void. 

This excess alcohol in the void will appear as a dark line 

between the bond lines of the doublers. 

CAUTION 

Pay particular attention not to remove any parent material 

from the skin / doublers during sanding operation 

BB

B
ASB 205B-08-51 

Page 4 of 6 

4. Carry out a detailed visual inspection of the top and bottom inspection areas of the 

blade using a 3X-power magnifying glass and a strong light source. Check for 

evidence of a dark line between doublers, grip plates and skin with excess alcohol 

bleeding out of possible edge voids. Any cracks in the finish must be investigated 

further by removing paint in affected areas (sand with 180-220 grit paper in a 

spanwise direction) to determine if the grip plate / doublers are cracked or voided. 

Any crack in paint finish which follows grip plate / doubler outline may indicate a 

possible edge void. 

5. If cracks in grip plate / doublers are found, the affected blade must be immediately 

removed from service. If no cracks are detected, continue with Step 6. 

CAUTION 

Pay particular attention not to remove any parent material 

from the skin / doublers during sanding operation. 

6. If edge voids between grip plate / doublers / skin are found, determine depth and 

length by using 0.0015 in. feeler gage. If edge voids are near outboard tip of grip 

plate / doublers, also carefully tap inspect suspect area. Refer to BHT-212-CR&O, 

62-8 thru 62-10 for void repair limits and inspection/repair instructions. If no voids 

are detected, continue with Step 7. 

7. Refinish the sanded area as per BHT-212-CR&O. 

8. Following the inspection, apply a light coat of preservative oil (C-125) to all 

surfaces of blade. 

9. Annotate records to indicate findings and compliance with this bulletin. 

B

B

B
ASB 205B-08-51 

Page 5 of 6 

Figure 1 

Inspection Area 

 

Station 

24.5 

Station 

85 
ASB 205B-08-51 

Page 6 of 6 

Figure 2 

Crack Indications