Narrative:

While climbing through 13000 ft TCASII alert with RA activated. RA called for climb. I spotted a B737 at 11 O'clock position, higher, sbound. I called for descend (RA called for climb), the captain pushed the nose over with 40 degrees right turn. RA changed to descend advisory. The B737 passed above and behind us at 14500 ft. We leveled off at 14000 ft. I believe that if we were to follow RA instruction (climb), a closer situation would have occurred. Supplemental information from acn 364135: copilot for a data collection flight. The aircraft is a non TCASII B737-200. The data collection was planned for 2 runs at 14500 ft. The PIC precoordinated the data collection pattern with baltimore TRACON, an oval pattern, 12 mi long and 6 mi wide. The aircraft was operated on a VFR clearance with radar TA's from baltimore approach with a mode 3 transponder code. Although there appeared to be no real collision threat, the air carrier airplane was maneuvering aggressively in a poorly planned collision avoidance turn and descent. I was surprised by the air carrier airplane's ineffective pitch and roll directions, as well as the aggressive pitch and roll rates. The air carrier airplane should have remained above our altitude and initially turned left, to pass behind our airplane. The right turn prolonged the crossing situation. The air carrier aircrew could use some training in visual maneuvering to control aircraft separation in aircraft crossing sits, or TCASII altitude and turn direction algorithms failed to recognize a turning aircraft crossing situation. No TA call was received by our airplane from baltimore approach. Our aircraft was close to the boundaries of 4 traffic control sectors and the air carrier airplane was talking to washington.

Related reports:

Google
 

Original NASA ASRS Text

Title: AN ACR B727 DSNDED AND TURNED TO AVOID A GOV B737. THE B737 WAS FLYING VFR IN A DATA COLLECTION PATTERN KNOWN TO BWI TRACON APCH CTL. SEE AND AVOID.

Narrative: WHILE CLBING THROUGH 13000 FT TCASII ALERT WITH RA ACTIVATED. RA CALLED FOR CLB. I SPOTTED A B737 AT 11 O'CLOCK POS, HIGHER, SBOUND. I CALLED FOR DSND (RA CALLED FOR CLB), THE CAPT PUSHED THE NOSE OVER WITH 40 DEGS R TURN. RA CHANGED TO DSND ADVISORY. THE B737 PASSED ABOVE AND BEHIND US AT 14500 FT. WE LEVELED OFF AT 14000 FT. I BELIEVE THAT IF WE WERE TO FOLLOW RA INSTRUCTION (CLB), A CLOSER SIT WOULD HAVE OCCURRED. SUPPLEMENTAL INFO FROM ACN 364135: COPLT FOR A DATA COLLECTION FLT. THE ACFT IS A NON TCASII B737-200. THE DATA COLLECTION WAS PLANNED FOR 2 RUNS AT 14500 FT. THE PIC PRECOORDINATED THE DATA COLLECTION PATTERN WITH BALTIMORE TRACON, AN OVAL PATTERN, 12 MI LONG AND 6 MI WIDE. THE ACFT WAS OPERATED ON A VFR CLRNC WITH RADAR TA'S FROM BALTIMORE APCH WITH A MODE 3 XPONDER CODE. ALTHOUGH THERE APPEARED TO BE NO REAL COLLISION THREAT, THE ACR AIRPLANE WAS MANEUVERING AGGRESSIVELY IN A POORLY PLANNED COLLISION AVOIDANCE TURN AND DSCNT. I WAS SURPRISED BY THE ACR AIRPLANE'S INEFFECTIVE PITCH AND ROLL DIRECTIONS, AS WELL AS THE AGGRESSIVE PITCH AND ROLL RATES. THE ACR AIRPLANE SHOULD HAVE REMAINED ABOVE OUR ALT AND INITIALLY TURNED L, TO PASS BEHIND OUR AIRPLANE. THE R TURN PROLONGED THE XING SIT. THE ACR AIRCREW COULD USE SOME TRAINING IN VISUAL MANEUVERING TO CTL ACFT SEPARATION IN ACFT XING SITS, OR TCASII ALT AND TURN DIRECTION ALGORITHMS FAILED TO RECOGNIZE A TURNING ACFT XING SIT. NO TA CALL WAS RECEIVED BY OUR AIRPLANE FROM BALTIMORE APCH. OUR ACFT WAS CLOSE TO THE BOUNDARIES OF 4 TFC CTL SECTORS AND THE ACR AIRPLANE WAS TALKING TO WASHINGTON.

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.