Citation V/Ultra/Encore (C560)
Flight Crew Air Transport Pilot (ATP)
Other / Unknown
ATC Issue All Types; Conflict Airborne Conflict; Deviation - Altitude Excursion From Assigned Altitude
Flight Crew Executed Go Around / Missed Approach; Flight Crew Took Evasive Action
Aircraft; Human Factors; Procedure
Coming in on the visual approach to 19L; the Tower informed us there was a helicopter that shouldn't be a factor. We saw the traffic on TCAS and decided to shallow the descent until clear of the traffic; which by this point was  -100 FT. We then got a TCAS RA (climb) and executed a missed approach. When we came around again; the traffic was in the same spot. I asked the Tower to move the traffic; which they were too slow to do. I maintained a higher altitude than I did the previous time until the traffic was no longer a factor and landed without further incident. I contacted the Tower via telephone after we landed and they said the helicopter was there mapping for a subway and 'no one else has had a RA from it.'  Traffic does not need to be at 1;000 AGL on a 3 mile final at an international airport.
Corporate aircraft responded to a TCAS RA on final for IAD 19L and executed a go-around; the pilot questioning ATC for allowing helicopter operations near the landing runway.