DATE 

### ALERT SERVICE BULLETIN

REVISION NOTICE

AN APPROPRIATE ENTRY SHOULD BE MADE IN TH E AIRCRAFT LOGBOOK UPON ACCOMPLISHMENT

IF OWNERSHIP OF AIRCRAFT HAS CHANGED PLEASE FORWARD TO NEW OWNER Jan 11, 2011

TO: All Owners/Operators of Bell 212 Helicopters

SUBJECT: REVISION “B” TO ALERT SE RVICE BULLETIN 212-08-130:

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 issu ed for an editorial change in the “DESCRIPTION” paragraph.

Revision “B” to this bulletin is being issued to change the inspection interval and procedure as well as adding additional blade part numbers. Changes were made to the following paragraphs: “SUBJECT ”, “HELICOPTERS AFFECTED”, “COMPLIANCE”, “DESCRIPTION”, and “A CCOMPLISHMENT INSTRUCTIONS”.NO.

DATE

PAGE DATE

REV 

### ALERT SERVICE BULLETIN

AN APPROPRIATE ENTRY SHOULD BE MADE IN TH E AIRCRAFT LOGBOOK UPON ACCOMPLISHMENT

IF OWNERSHIP OF AIRCRAFT HAS CHANGED PLEASE FORWARD TO NEW OWNER 212-08-130

01/11/2011 Dec 19, 2008

B 1 of 6

MODEL AFFECTED: 212

SUBJECT: MAIN ROTOR BLADE P/N 212-015-501-005, -111, -113, -115, -117, -119 and, -121, 204-012-001-023 and, -033, INSPECTION OF.

HELICOPTERS AFFECTED: Model 212 helicopters serial number 30502 through 30603, 30611 through 30999, 31101 through 31311, 35001 through 35103, and 32101 through 32142.

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 approx imately 1000 hours total time was recently returned to BHTI for evaluation. The blade was found cracked through the blade retention bolt hole at Blad e Station 28.0 and another crack through the lower grip plate at Blad e Station 36.0. The main roto r 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 i nadequate bond between th e 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 th is bulletin are FAA/ODA approved.

MANPOWER: B B B BASB 212-08-130 Page 2 of 6

Approximately 1.0 man-hour is required to comply with this bulletin. Man-hours are based on hands-on time, and may vary wit h personnel and facilities available.

WARRANTY:

There is no warranty provided for this bulletin.

MATERIAL:

Required Material:

None required

Consumable Material:

The following material is required to acco mplish this bulletin, but may not require ordering, depending on t he operator’s consumable material stock levels. This material may be obtained through the Bell Heli copter Textron Supply Centers.

Part Number Nomenclature Quantity Reference

MILC87936TY1 Cleaning Co mpound 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 ManualASB 212-08-130 Page 3 of 6

BHT-212-CR&O Component Repa ir and Overhaul Manual

PUBLICATIONS AFFECTED:

BHT-212-MM Maintenance Manual

ACCOMPLISHMENT INSTRUCTIONS:

1. Wash upper and lower Main Rotor Bl ade surfaces with a solution of cleaning compound (C-318) and water. Rin se 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 Bl ade upper and lower grip plates and doublers for their entire length and chord width. Inspect fo r signs of cracks, corrosion and edge voids, paying particular attention to the bond lines between doubler s, grip plates and skin. Hair line cracks in the paint fini sh should be suspect for possible cracks /

voids.

3. Wipe the area to be inspec ted 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 po tential cracks in the bond

lines between doublers or grip plates will be indicated by the presence of excess alcohol bl eeding 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 BASB 212-08-130 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 glas s and a strong light source. Check for

evidence of a dark line betw een doublers, grip plates and skin with excess alcohol bleeding out of possible edge voids. Any cra cks in the finish must be investigated further by removing paint in affected areas (sand with 180-220 grit paper in a spanwise direction) to determi ne if the grip plate / doublers are cracked or voided. Any crack in paint finish which follows gr ip plate / doubler outline may indicate a possible edge void.

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

removed from service. If no cracks are detected, c ontinue 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 / doubler s / skin are found, determine depth and length by using 0.0015 in. feeler gage. If edge voids are near out board tip of grip plate / doublers, also carefully tap inspec t suspect area. Refer to BHT-212-CR&O, 62-8 thru 62-10 for void repair limits and in spection/repair instructions. If no voids
are detected, cont inue with Step 7.

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

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

surfaces of blade.

9. Annotate records to indicate findi ngs and compliance with this bulletin. B

B

BASB 212-08-130 Page 5 of 6

Figure 1 Inspection Area 

### Station

24.5 Station

85ASB 212-08-130 Page 6 of 6

Figure 2

Crack Indications