Narrative:

I was first officer on flight X bwi to lynchburg, va on 4/mon/90. It was my leg. We had departed bwi VFR and climbed to 10500'. Bwi departure had handed us off to ZDC. We had been idented by ZDC and were in level flight. The captain called traffic at 3 O'clock. I saw the other air carrier flight in a climbing left turn. He had overtaken us from our right rear and was climbing into our flight path. ZDC had not advised either of us of mutual traffic, and the medium large transport had obviously not seen us. I pitched up and turned right to put us above and behind the medium large transport. We climbed to about 11000' to maintain sep the controller then apologized, saying that he had thought that we were at 8500' (we were squawking mode C). The controller was not using the information that was on (or available on) his scope. He turned an IFR departure into a known VFR that he was working. We were lucky to see him since he was coming from behind and below. The other crew apparently did not see us until after we had taken evasive action. Supplemental information from acn 143617: flight Y, flying from dca-tpa. The captain was flying. An NTSB accident investigator was on the jump seat listening on a headset. While on ZDC frequency 121.05 we were cleared from level flight at 9000' to 15000'. Climb was initiated. Passing 10500' I happened to looked out captain's rear-most side window (#3), where I saw an small transport twin type aircraft extremely close in a slightly nose up attitude. I immediately indicated the conflict to the captain, who stopped the climb. The aircraft subsequently idented as air carrier flight X passed overhead within 500'. The captain resumed climbing to 15000' and I asked the controller the altitude of the aircraft which had just passed over us. The controller said it was a VFR flight. The controller and the other crew then had a brief exchange which indicated some confusion as to what altitude the small transport was supposed to be at.

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Original NASA ASRS Text

Title: NMAC.

Narrative: I WAS F/O ON FLT X BWI TO LYNCHBURG, VA ON 4/MON/90. IT WAS MY LEG. WE HAD DEPARTED BWI VFR AND CLBED TO 10500'. BWI DEP HAD HANDED US OFF TO ZDC. WE HAD BEEN IDENTED BY ZDC AND WERE IN LEVEL FLT. THE CAPT CALLED TFC AT 3 O'CLOCK. I SAW THE OTHER ACR FLT IN A CLBING LEFT TURN. HE HAD OVERTAKEN US FROM OUR RIGHT REAR AND WAS CLBING INTO OUR FLT PATH. ZDC HAD NOT ADVISED EITHER OF US OF MUTUAL TFC, AND THE MLG HAD OBVIOUSLY NOT SEEN US. I PITCHED UP AND TURNED RIGHT TO PUT US ABOVE AND BEHIND THE MLG. WE CLBED TO ABOUT 11000' TO MAINTAIN SEP THE CTLR THEN APOLOGIZED, SAYING THAT HE HAD THOUGHT THAT WE WERE AT 8500' (WE WERE SQUAWKING MODE C). THE CTLR WAS NOT USING THE INFO THAT WAS ON (OR AVAILABLE ON) HIS SCOPE. HE TURNED AN IFR DEP INTO A KNOWN VFR THAT HE WAS WORKING. WE WERE LUCKY TO SEE HIM SINCE HE WAS COMING FROM BEHIND AND BELOW. THE OTHER CREW APPARENTLY DID NOT SEE US UNTIL AFTER WE HAD TAKEN EVASIVE ACTION. SUPPLEMENTAL INFO FROM ACN 143617: FLT Y, FLYING FROM DCA-TPA. THE CAPT WAS FLYING. AN NTSB ACCIDENT INVESTIGATOR WAS ON THE JUMP SEAT LISTENING ON A HEADSET. WHILE ON ZDC FREQ 121.05 WE WERE CLRED FROM LEVEL FLT AT 9000' TO 15000'. CLB WAS INITIATED. PASSING 10500' I HAPPENED TO LOOKED OUT CAPT'S REAR-MOST SIDE WINDOW (#3), WHERE I SAW AN SMT TWIN TYPE ACFT EXTREMELY CLOSE IN A SLIGHTLY NOSE UP ATTITUDE. I IMMEDIATELY INDICATED THE CONFLICT TO THE CAPT, WHO STOPPED THE CLB. THE ACFT SUBSEQUENTLY IDENTED AS ACR FLT X PASSED OVERHEAD WITHIN 500'. THE CAPT RESUMED CLBING TO 15000' AND I ASKED THE CTLR THE ALT OF THE ACFT WHICH HAD JUST PASSED OVER US. THE CTLR SAID IT WAS A VFR FLT. THE CTLR AND THE OTHER CREW THEN HAD A BRIEF EXCHANGE WHICH INDICATED SOME CONFUSION AS TO WHAT ALT THE SMT WAS SUPPOSED TO BE AT.

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.