Climbing large transport has near midair collision with another aircraft.

Attributes
ACN	143720
Time
Date	199004
Day	Thu
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : cvg airport : day
State Reference	OH
Altitude	msl bound lower : 12500 msl bound upper : 13000
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Controlling Facilities	artcc : zid
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : second officer
Qualification	pilot : flight engineer pilot : cfi pilot : atp
Experience	flight time last 90 days : 160 flight time total : 4900 flight time type : 650
ASRS Report	143720
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : commercial pilot : instrument pilot : atp
Experience	flight time last 90 days : 186 flight time total : 15000 flight time type : 3000
ASRS Report	143940
Events
Anomaly	conflict : nmac
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	faa : investigated
Miss Distance	horizontal : 400 vertical : 200
Supplementary
Primary Problem	Ambiguous

Narrative:

Climbing through approximately 17000', we noticed an aircraft at our 12 O'clock position and converging. After looking at it for awhile and trying to figure out which way it was going to pass, we discovered that we were coming together head-on, on a collision course. We pulled up and the other aircraft descended sharply in a left turn, just passing below us to our right side. I am confident that if evasive action wasn't taken by both aircraft, we would have collided. Fortunately, all 3 crew members were looking outside, because from the time of first seeing him to the time of near miss was less than 30 seconds, and he was never pointed out by ATC. I think the installation of TCAS equipment in all part 121 aircraft would greatly reduce if not eliminate such occurrences. Also, requiring mode C xponders in all aircraft. Supplemental information from acn 143940: saw traffic at 12 O'clock position and turned on landing lights. Could not tell at first if traffic was converging. It was necessary to pull up sharply to avoid a midair collision. ATC did not call the traffic, but after I told them of our near miss, was advised they had a mode C target at 12500'.

Original NASA ASRS Text

Title: CLIMBING LGT HAS NMAC WITH ANOTHER ACFT.

Narrative: CLIMBING THROUGH APPROX 17000', WE NOTICED AN ACFT AT OUR 12 O'CLOCK POSITION AND CONVERGING. AFTER LOOKING AT IT FOR AWHILE AND TRYING TO FIGURE OUT WHICH WAY IT WAS GOING TO PASS, WE DISCOVERED THAT WE WERE COMING TOGETHER HEAD-ON, ON A COLLISION COURSE. WE PULLED UP AND THE OTHER ACFT DESCENDED SHARPLY IN A LEFT TURN, JUST PASSING BELOW US TO OUR RIGHT SIDE. I AM CONFIDENT THAT IF EVASIVE ACTION WASN'T TAKEN BY BOTH ACFT, WE WOULD HAVE COLLIDED. FORTUNATELY, ALL 3 CREW MEMBERS WERE LOOKING OUTSIDE, BECAUSE FROM THE TIME OF FIRST SEEING HIM TO THE TIME OF NEAR MISS WAS LESS THAN 30 SECONDS, AND HE WAS NEVER POINTED OUT BY ATC. I THINK THE INSTALLATION OF TCAS EQUIPMENT IN ALL PART 121 ACFT WOULD GREATLY REDUCE IF NOT ELIMINATE SUCH OCCURRENCES. ALSO, REQUIRING MODE C XPONDERS IN ALL ACFT. SUPPLEMENTAL INFORMATION FROM ACN 143940: SAW TFC AT 12 O'CLOCK POSITION AND TURNED ON LNDG LIGHTS. COULD NOT TELL AT FIRST IF TFC WAS CONVERGING. IT WAS NECESSARY TO PULL UP SHARPLY TO AVOID A MIDAIR COLLISION. ATC DID NOT CALL THE TFC, BUT AFTER I TOLD THEM OF OUR NEAR MISS, WAS ADVISED THEY HAD A MODE C TARGET AT 12500'.

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.