Just too busy recently!
Resume the repair job
Sand the foam to the shape of the airfoil
Cut carbon fiber cloth to proper size
Use packing tape to hold the carbon fiber in order and fine tune the size to the match the hole
Vacuum bag? Not exactly. I used heat shrinking plastic transparent sheet to cover the carbon cloth, push out the air and tape it in place so that I can use a hot hair dryer to heat the shrinking sheet. The effect is just like vacuum bag.
After a day of setting, the masking tape is removed. It looks ok although not perfect as I want
The bottom side is a bit better
The shape is reasonable. More fine tuning and sanding to remove some irregularities are needed.
