Narrative:

I was climbing northwest up the river at approximately 2500' heading approximately 325 degree when ATC said to turn right 'immediately' to 080. We had been cleared to 11,000'. He then called crossing traffic right to left at 3300'. I stopped my climb and an small transport passed right over the cockpit some 300 to 400'. (?) I fully believe that had I kept climbing, we would have collided. After talking to ATC, they said the small transport had departed dca ahead of us from runway 33 and been instructed to fly 280 degree after departure. I departed runway 36 and turned to approximately 325 degree up the river for noise abatement. I don't know how he got north of my track!

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Original NASA ASRS Text

Title: ACR TOOK EVASIVE ACTION TO MISS AN SMT AFTER DEP.

Narrative: I WAS CLIMBING NW UP THE RIVER AT APPROX 2500' HDG APPROX 325 DEG WHEN ATC SAID TO TURN RIGHT 'IMMEDIATELY' TO 080. WE HAD BEEN CLRED TO 11,000'. HE THEN CALLED XING TFC RIGHT TO LEFT AT 3300'. I STOPPED MY CLIMB AND AN SMT PASSED RIGHT OVER THE COCKPIT SOME 300 TO 400'. (?) I FULLY BELIEVE THAT HAD I KEPT CLIMBING, WE WOULD HAVE COLLIDED. AFTER TALKING TO ATC, THEY SAID THE SMT HAD DEPARTED DCA AHEAD OF US FROM RWY 33 AND BEEN INSTRUCTED TO FLY 280 DEG AFTER DEP. I DEPARTED RWY 36 AND TURNED TO APPROX 325 DEG UP THE RIVER FOR NOISE ABATEMENT. I DON'T KNOW HOW HE GOT N OF MY TRACK!

Data retrieved from NASA's ASRS site as of August 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.