Medium Large Transport; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP)
Situational Awareness
ATC Issue All Types; Conflict Airborne Conflict
Flight Crew Took Evasive Action
Human Factors; Procedure
We were entering a right base leg for Runway 3 in Lihue. About 5 miles out the Tower pointed us as traffic to a departing helicopter. The helicopter said they had us in sight. The Tower told the helicopter to remain clear of us and to pass behind us.  We just passed the centerline of Runway 35 fully configured for landing all lights on and approximately 1;000 FT. As we approached the middle of the bay and were descending we had TCAS traffic; the TCAS symbol was red; 200 FT below us and in a climb. The TCAS symbol was overlapping our airplane symbol on our PFD.  The First Officer called the traffic and said it looked like it was heading towards us. I stopped descending until we were clear of the traffic.  Once clear we were now high on the approach and had to bank sharper than normal to turn final. We stabilized about 400 FT and made a normal landing. It was determined that an event occurred because our TCAS alerted us 'TRAFFIC ; TRAFFIC.' Also by the TCAS symbol of the helicopter being RED; 200 FT below us and CLIMBING; and visually seeing it in what looked like it was turning towards us. This is the second day in a row that this has happened. It was exactly the same scenario i.e.: the Tower pointed us out to the helicopter. The helicopter pilot reported us in sight. The Tower told the helicopter pilot to maintain visual separation. The helicopters are flying right into or near our final approach path. If they know that we have to fly our base leg through the bay area; they should not be allowed to depart through the bay and more separation is required.  It's not good enough that they see us and we don't see them until we get a TCAS TA or RA. We are below 1;000 FT and don't have much room to deviate to avoid a collision. Once we received the TCAS warning we stopped descending extended our base leg and turned final later. Keep the helicopters further away from the approach area when an airplane is on approach.
Air carrier Captain reports an airborne conflict with a helicopter that had been instructed to maintain visual separation during departure as the reporter was on a visual approach at LIH.