Narrative:

I was captain and pilot not flying on a flight to dca. Contacting potomac approach we were told to expect the river visual to runway 19. After being cleared for the approach we were instructed to maintain 180K till 5 DME. At approximately 4-6 miles out we were then told to contact tower. Everything up till this point seemed to be normal VFR operations into dca. Upon contacting tower; we were cleared to land and asked to make the first available turn off. This led me to believe that we had traffic close behind also on the river visual. Around 1000ft AGL tower asked if we could accept runway 15. I responded; 'negative'. From this point on things happened very quickly and I will try to be as detailed as I can.after declining runway 15; tower instructed us that we were now #2 cleared to land 19. I was confused at the time because we were now crossing over the arlington memorial bridge around 700ft AGL and I had no traffic in front of us in sight. Very shortly thereafter; approximately 500 AGL; we received a TA coming from the east about 100ft above our altitude. At this point we were just about to turn final. I quickly looked to my 10-11 o'clock and saw a jetstream starting to cross directly in front of our flight path. My first officer maintained heading momentarily and delayed the turn to final. This kept us from receiving what I believe would have been an imminent RA at very low altitude. Before we had a chance to respond; the pilot of jetstream initiated a go around. We went slightly through final but were able turn in for a normal landing. At no time was the approach unstabilized. From my perception of the event; I believe if both aircraft had continued on tower instructions we would have been 3-5 seconds from a possible mid air collision.both myself and the pilot of the jetstream made it verbally clear to tower that we were not happy with what had just occurred. I am filing this report for safety awareness. I do not believe that we did anything incorrectly during this incident. My issues are that we were never properly made aware that other traffic was approaching from the east. There also clearly was not proper separation. I personally have never seen aircraft make left traffic over the potomac for runway 19. Thinking back; I do remember seeing a target to the east on TCAS; but it is commonplace to have helicopter traffic around 300-500 AGL in that area. I believe loss of separation was caused by improper vectoring from approach control. I personally made a phone call to tower after arriving at our gate and the supervisor working confirmed this. She indicated to me that approach had vectored both aircraft in tightly and basically dumped it on the tower to figure out how to coordinate the landings.this whole event occurred in what I perceived to be a 6-8 second time frame. I would say this only reinforces the fact that flight crews need to be extra vigilant conducting flight operations in high traffic areas and special use airports such as washington national. And also to never completely rely on ATC to maintain aircraft separation.

Google
 

Original NASA ASRS Text

Title: An E-170 flight crew on the River Visual to DCA experienced a close encounter on short final with an aircraft inbound to the same runway apparently on a left visual approach for the same runway. Neither approach control nor the tower advised of the conflicting traffic.

Narrative: I was Captain and Pilot Not Flying on a flight to DCA. Contacting Potomac Approach we were told to expect the River Visual to Runway 19. After being cleared for the approach we were instructed to maintain 180K till 5 DME. At approximately 4-6 miles out we were then told to contact Tower. Everything up till this point seemed to be normal VFR operations into DCA. Upon contacting Tower; we were cleared to land and asked to make the first available turn off. This led me to believe that we had traffic close behind also on the River Visual. Around 1000ft AGL Tower asked if we could accept Runway 15. I responded; 'negative'. From this point on things happened very quickly and I will try to be as detailed as I can.After declining Runway 15; Tower instructed us that we were now #2 cleared to land 19. I was confused at the time because we were now crossing over the Arlington Memorial Bridge around 700ft AGL and I had no traffic in front of us in sight. Very shortly thereafter; approximately 500 AGL; we received a TA coming from the east about 100ft above our altitude. At this point we were just about to turn final. I quickly looked to my 10-11 o'clock and saw a Jetstream starting to cross directly in front of our flight path. My First Officer maintained heading momentarily and delayed the turn to final. This kept us from receiving what I believe would have been an imminent RA at very low altitude. Before we had a chance to respond; the pilot of Jetstream initiated a go around. We went slightly through final but were able turn in for a normal landing. At no time was the approach unstabilized. From my perception of the event; I believe if both aircraft had continued on Tower instructions we would have been 3-5 seconds from a possible mid air collision.Both myself and the pilot of the Jetstream made it verbally clear to Tower that we were not happy with what had just occurred. I am filing this report for safety awareness. I do not believe that we did anything incorrectly during this incident. My issues are that we were never properly made aware that other traffic was approaching from the east. There also clearly was not proper separation. I personally have never seen aircraft make left traffic over the Potomac for Runway 19. Thinking back; I do remember seeing a target to the east on TCAS; but it is commonplace to have helicopter traffic around 300-500 AGL in that area. I believe loss of separation was caused by improper vectoring from approach control. I personally made a phone call to Tower after arriving at our gate and the Supervisor working confirmed this. She indicated to me that Approach had vectored both aircraft in tightly and basically dumped it on the Tower to figure out how to coordinate the landings.This whole event occurred in what I perceived to be a 6-8 second time frame. I would say this only reinforces the fact that flight crews need to be extra vigilant conducting flight operations in high traffic areas and special use airports such as Washington National. And also to never completely rely on ATC to maintain aircraft separation.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.