Air carrier came in close proximity on departure with an aircraft on downwind for converging runway.

Attributes
ACN	139553
Time
Date	199003
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : sba
State Reference	CA
Altitude	msl bound lower : 600 msl bound upper : 800
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : sba
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	climbout : takeoff climbout : initial
Route In Use	departure other
Flight Plan	IFR
Aircraft 2
Operator	general aviation : personal
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	landing other other
Flight Plan	None
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 90 flight time total : 12000 flight time type : 4400
ASRS Report	139553
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	conflict : nmac non adherence : published procedure other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 0 vertical : 200
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

We took off from sba runway 25 and had to take evasive action to avoid a conflict with a single engine aircraft on right downwind runway 15. We were climbing at approximately 1500 FPM with an airspeed of 145 KIAS when at approximately 600' AGL we noticed an aircraft moving from 11 O'clock to 12 O'clock slightly ahead and above us. It appeared that at our current speed and rate of climb that a collision was possible. I instructed the first officer to level off and simultaneously applied forward pressure on the yoke. He promptly and smoothly stopped the climb and descended slightly to avoid the other aircraft. Tower was contacted to advise them of the traffic. Their response was 'it was in the pattern'. We were never advised of any other aircraft in the area. In my next radio transmission, I advised the tower that we had taken evasive action. In my opinion, having this downwind operation crossing over the departure end of a runway is extremely dangerous and that a possible mid-air collision was avoided only by our chance sighting of this other aircraft. I advised sba tower on 3/fri/90 that we were calling this a 'near miss'.

Original NASA ASRS Text

Title: ACR CAME IN CLOSE PROX ON DEP WITH AN ACFT ON DOWNWIND FOR CONVERGING RWY.

Narrative: WE TOOK OFF FROM SBA RWY 25 AND HAD TO TAKE EVASIVE ACTION TO AVOID A CONFLICT WITH A SINGLE ENG ACFT ON R DOWNWIND RWY 15. WE WERE CLBING AT APPROX 1500 FPM WITH AN AIRSPD OF 145 KIAS WHEN AT APPROX 600' AGL WE NOTICED AN ACFT MOVING FROM 11 O'CLOCK TO 12 O'CLOCK SLIGHTLY AHEAD AND ABOVE US. IT APPEARED THAT AT OUR CURRENT SPD AND RATE OF CLB THAT A COLLISION WAS POSSIBLE. I INSTRUCTED THE F/O TO LEVEL OFF AND SIMULTANEOUSLY APPLIED FORWARD PRESSURE ON THE YOKE. HE PROMPTLY AND SMOOTHLY STOPPED THE CLB AND DSNDED SLIGHTLY TO AVOID THE OTHER ACFT. TWR WAS CONTACTED TO ADVISE THEM OF THE TFC. THEIR RESPONSE WAS 'IT WAS IN THE PATTERN'. WE WERE NEVER ADVISED OF ANY OTHER ACFT IN THE AREA. IN MY NEXT RADIO XMISSION, I ADVISED THE TWR THAT WE HAD TAKEN EVASIVE ACTION. IN MY OPINION, HAVING THIS DOWNWIND OPERATION XING OVER THE DEP END OF A RWY IS EXTREMELY DANGEROUS AND THAT A POSSIBLE MID-AIR COLLISION WAS AVOIDED ONLY BY OUR CHANCE SIGHTING OF THIS OTHER ACFT. I ADVISED SBA TWR ON 3/FRI/90 THAT WE WERE CALLING THIS A 'NEAR MISS'.

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.