Narrative:

I was in an medium large transport and just departed dca north up river. At about 800 ft AGL, when TCASII became uninhibited, got a TA on traffic approaching us at 2400 ft AGL. I was 20 degrees of pitch (normal body angle for an medium large transport) and had a vsi of about 3500-4500 FPM. About 2 seconds later, got a 'descend' RA and I stopped climb as soon as possible at about 2000 ft when a single engine small aircraft went overhead about 400 ft above us. We were both in TCA. I was in VFR conditions but IFR flight plan. The small aircraft had either brushed, or barely brushed P56 and was swbound toward dca (or a point about 1 mi north of airport center, the controllers said they were unaware of aircraft till we told them, however, the small aircraft did, in fact, have a mode C operating or we would not have picked him up as an intruder. The controllers should have seen him, should have told us and maybe this would not have happened. Later on departure, controller told us 'sorry about that,' gave us a phone number and, when called 2 hours later, said target small aircraft was still swbound over richmond, va. Just goes to show you: even VFR conditions in a TCA (within 1 DME of dca and 1 DME from P-56) see and be seen still applies. Also noted, TCASII works.

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Original NASA ASRS Text

Title: NMAC IN TCA.

Narrative: I WAS IN AN MLG AND JUST DEPARTED DCA N UP RIVER. AT ABOUT 800 FT AGL, WHEN TCASII BECAME UNINHIBITED, GOT A TA ON TFC APCHING US AT 2400 FT AGL. I WAS 20 DEGS OF PITCH (NORMAL BODY ANGLE FOR AN MLG) AND HAD A VSI OF ABOUT 3500-4500 FPM. ABOUT 2 SECONDS LATER, GOT A 'DSND' RA AND I STOPPED CLB ASAP AT ABOUT 2000 FT WHEN A SINGLE ENG SMA WENT OVERHEAD ABOUT 400 FT ABOVE US. WE WERE BOTH IN TCA. I WAS IN VFR CONDITIONS BUT IFR FLT PLAN. THE SMA HAD EITHER BRUSHED, OR BARELY BRUSHED P56 AND WAS SWBOUND TOWARD DCA (OR A POINT ABOUT 1 MI N OF ARPT CTR, THE CTLRS SAID THEY WERE UNAWARE OF ACFT TILL WE TOLD THEM, HOWEVER, THE SMA DID, IN FACT, HAVE A MODE C OPERATING OR WE WOULD NOT HAVE PICKED HIM UP AS AN INTRUDER. THE CTLRS SHOULD HAVE SEEN HIM, SHOULD HAVE TOLD US AND MAYBE THIS WOULD NOT HAVE HAPPENED. LATER ON DEP, CTLR TOLD US 'SORRY ABOUT THAT,' GAVE US A PHONE NUMBER AND, WHEN CALLED 2 HRS LATER, SAID TARGET SMA WAS STILL SWBOUND OVER RICHMOND, VA. JUST GOES TO SHOW YOU: EVEN VFR CONDITIONS IN A TCA (WITHIN 1 DME OF DCA AND 1 DME FROM P-56) SEE AND BE SEEN STILL APPLIES. ALSO NOTED, TCASII WORKS.

Data retrieved from NASA's ASRS site as of July 2007 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.