Reporter received TCASII RA and as an evasive action stopped descent and turned.

Attributes
ACN	322096
Time
Date	199511
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : bwi
State Reference	MD
Altitude	msl bound lower : 12000 msl bound upper : 12000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : bwi
Operator	common carrier : air carrier
Make Model Name	B727 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	descent other
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 130
ASRS Report	322096
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	conflict : airborne less severe other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 3000 vertical : 0
Supplementary
Air Traffic Incident	other

Narrative:

Told to 'cross clipper at 12000 ft.' we were descending through 13500 ft when TCASII gave TA. I called bwi approach (TCASII showed target 12 O'clock, 1500 ft low and climbing) to ask but was blocked first time by another aircraft's transmission. At 12800 ft got RA 'climb.' told first officer to stop descent and jog to right. Called bwi again and they said there was a VFR aircraft near us that they thought was being controled by 'new york'. A twin engine commuter type which I believe to have been air carrier X passed just off our left, co-altitude, and climbing, according to TCASII after we returned to normal flight profile, I told balance approach I thought the other aircraft had been 'very close' to us. Controller said (I don't remember exact words) 'that aircraft was VFR and not under my control.'

Original NASA ASRS Text

Title: RPTR RECEIVED TCASII RA AND AS AN EVASIVE ACTION STOPPED DSCNT AND TURNED.

Narrative: TOLD TO 'CROSS CLIPPER AT 12000 FT.' WE WERE DSNDING THROUGH 13500 FT WHEN TCASII GAVE TA. I CALLED BWI APCH (TCASII SHOWED TARGET 12 O'CLOCK, 1500 FT LOW AND CLBING) TO ASK BUT WAS BLOCKED FIRST TIME BY ANOTHER ACFT'S XMISSION. AT 12800 FT GOT RA 'CLB.' TOLD FO TO STOP DSCNT AND JOG TO R. CALLED BWI AGAIN AND THEY SAID THERE WAS A VFR ACFT NEAR US THAT THEY THOUGHT WAS BEING CTLED BY 'NEW YORK'. A TWIN ENG COMMUTER TYPE WHICH I BELIEVE TO HAVE BEEN ACR X PASSED JUST OFF OUR L, CO-ALT, AND CLBING, ACCORDING TO TCASII AFTER WE RETURNED TO NORMAL FLT PROFILE, I TOLD BAL APCH I THOUGHT THE OTHER ACFT HAD BEEN 'VERY CLOSE' TO US. CTLR SAID (I DON'T REMEMBER EXACT WORDS) 'THAT ACFT WAS VFR AND NOT UNDER MY CTL.'

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.