Preliminary Requirements

Procedure

1. SUBTASK 72-32-85-350-089 Remove Defective Area of Damage

   1. 
      CAUTION
      CHECK THE TOTAL REPAIR AREA PRIOR TO STARTING THE REPAIR. DO NOT CARRY OUT REPAIR BY FILLING THE ANTI ICE IMPACT PANELS IF THE TOTAL REPAIRED AREA EXCEEDS 20 PERCENT OF THE THE TOTAL FAN CASE ANTI ICE IMPACT PANEL AREA.
      
      CAUTION
      THE FAN CASE IS MADE FROM TITANIUM ALLOY AND IS THIN IN SOME AREAS. IF YOU HIT THE FAN CASE WITH A CHISEL OR SCRAPER YOU CAN MAKE IT UNSERVICEABLE.
      
      CAUTION
      YOU MUST USE THE CHISEL, SHARP BLADE OR SCRAPER IN A CIRCUMFERENTIAL DIRECTION TO PREVENT THE EDGES OF THE BLADE SCORING THE FAN CASE.
      
      CAUTION
      STOP MACHINING AS SOON AS THE FILES, CUTTERS OR MACHINING BITS ARE THROUGH THE LINING MATERIAL. USE A STOP-MACHINING OR SLEEVE OR OTHER PENETRATION LIMITING DEVICE TO PREVENT DAMAGE TO THE CASING MATERIAL.
      
      CAUTION
      DO NOT USE POWERED TOOLS WITH STEEL CHISEL OR SIMILAR BITS.
      
      CAUTION
      YOU MUST ALWAYS TRY TO POINT THE CHISEL OR SHARP BLADE PARALLEL WITH THE SURFACE OF THE FAN CASE.
      
      CAUTION
      DO NOT OPERATE WITHOUT SAFETY GOGGLES AND OTHER GUARD EQUIPMENT. FLYING PARTICLES CAN CAUSE INJURY.

      NOTE

      Keep the material removal to the minimum necessary damaged area.

      Cut away area to remove broken pieces or make a hole with grinder or file for filling into damaged area.

      1. Use hand held pneumatic grinder and rotary files.

      2. Refer to Figure.

      3. Be careful not to cause damage to the inner surface of the fan case assembly.

   2. Examine the Glass Reinforced Composite (GRC) skin and check for indications of blistering or lack of bond by pressing or tapping.

      1. Check visually and by tapping.

      2. A hollow sound indicative of a suspect bond. Remove any unsound material.

      3. If the repaired area on the ice impact panel exceeds 20 percent of the total area, replace it.

      4. Repair to VRS1539 TASK 72-32-85-300-024.

      5. Be careful not to cause damage to the inner surface of the fan case assembly.

   3. Examine the repaired area ratio.

      1. Repaired area ratio must not be more than 20 percent of one segment of anti-ice impact panel.

      2. If more than 20 percent, replace it.

      3. Repair to VRS1539 TASK 72-32-85-300-024 (REPAIR-024).

   4. Make rough the repair areas.

      1. Use CoMat 05-016 GARNET PAPER, 80-GRIT.

   5. Remove any remaining debris.

      1. Use vacuum cleaner.

   6. Examine the fan case inner surface of the repaired area, if necessary.

      1. Examine the fan case inner surface, if necessary.

      2. Repair any nicks, dents, scratches and gouges.

      3. If necessary, do Repair, VRS1554, TASK 72-32-85-300-016 (REPAIR-016).

2. SUBTASK 72-32-85-110-057 Remove the Grease from the Repair Area

   1. 
      WARNING
      ALWAYS MAKE SURE THERE IS SUFFICIENT VENTILATION IN THE WORK AREA. EYE PROTECTION MUST ALWAYS BE USED. DO NOT LET THE SOLVENT CLEANER OR ITS VAPOR TOUCH THE EYES OR SKIN. PROTECTIVE CLOTHING AND FACE MASKS MUST ALWAYS BE USED. ALWAYS KEEP OPEN FLAMES AWAY FROM THE WORK AREA. IT IS THE RESPONSIBILITY OF THE OPERATOR TO OBTAIN AND OBSERVE THE MANUFACTURERS MATERIAL SAFETY SHEETS FROM THE CONSUMABLE MATERIALS INFORMATION SUCH AS HAZARDOUS INGREDIENTS, PHYSICAL/CHEMICAL CHARACTERISTICS, FIRE, EXPLOSION, REACTIVITY, HEALTH HAZARD DATA, PRECAUTIONS FOR SAFE HANDLING, USE AND CONTROL MEASURES AND ALSO TO TAKE LOCAL REGULATIONS INTO CONSIDERATION.

      Fully remove the grease from the repair area except the blue filler surface.

      1. Refer to the SPM TASK 70-11-26-300-503.

      2. Use CoMat 01-076 METHYL ETHYL KETONE with CoMat 02-099 LINT-FREE CLOTH.

   2. Immediately dry out area with air blast.

      1. Use oil free dry air.

3. SUBTASK 72-32-85-360-074 Prepare Filler Material

   1. OPTION 1: Use CoMat 08-006 FILLER, TWO PACK.

      1. Measure out materials by weight.

         1. Refer to the SPM TASK 70-36-02-360-501.

         2. Use CoMat 08-006 FILLER, TWO PACK.

      2. Mix the two parts by kneading until the paste is a constant blue color. No streaks permitted.

         1. Use putty knife.

   2. NOTE

      You must use plastic gloves, during preparation and use of the sealant, to prevent contamination of the skin.

      NOTE

      When mixed the life of the filler is approximately half an hour at 77 deg F (25 deg C).

      OPTION 2: Use CoMat 08-024 SEALANT or CoMat 08-142 POLYSULPHIDE COMPOUND.

      1. Prepare the sealant material.

         1. Use CoMat 08-024 SEALANT or CoMat 08-142 POLYSULPHIDE COMPOUND 75 parts of base compound and 10 parts of curing compound (accelerator) by weight.

         2. Mix the two parts by kneading until the compound is a constant color.

         3. No streaks permitted.

4. SUBTASK 72-32-85-360-075 Apply Filler Material

   1. Fill the filler slightly more than the necessary level in the damaged area.

      1. Refer to the SPM TASK 70-36-02-360-501.

      2. Use air powered sealant gun.

   2. Cure the filler.

      1. 
         CAUTION
         THE MAXIMUM TEMPERATURE WHICH CAN BE USED TO CURE THE FILLER MATERIAL (CoMat 08-006 FILLER, TWO PACK) IS 176 DEG F (80 DEG C).

         Cure the filler, two pack (CoMat 08-006 FILLER, TWO PACK).

         1. The cure times and temperatures are given in Figure.

      2. 
         CAUTION
         THE MAXIMUM TEMPERATURE WHICH CAN BE USED TO CURE THE SEALANT (CoMat 08-024 SEALANT OR CoMat 08-142 POLYSULPHIDE COMPOUND) IS 120 DEG F (49 DEG C).

         NOTE

         The minimum cure time is one hour.

         Cure the sealant material (CoMat 08-024 SEALANT or CoMat 08-142 POLYSULPHIDE COMPOUND).

         1. NOTE

            The minimum cure time is 1.5 hours. Sealant cure times with a relative humidity of 50 percent.

            Cure the sealant for 10 hours at 77 deg F (25 deg C) or 1.5 hours at 113 deg F (45 deg C).

5. SUBTASK 72-32-85-220-103 Visually Inspect

   1. Examine the surface of the repaired area.

      1. Make sure that the shape of the filling surface is smooth and flat.

      2. Step is acceptable if less than 0.02 in. (0.5 mm).

      3. If necessary, do this TASK again.

      4. Refer to Figure.

Figure: Filling repair of anti ice impact panel

Filling repair of anti ice impact panel



Figure: Curing chart of filling material (CoMat 08-006)

Curing chart of filling material (CoMat 08-006)