Near midair collision between commuter aircraft and light single engine aircraft.

Attributes
ACN	120100
Time
Date	198908
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : mzb airport : san
State Reference	CA
Altitude	msl bound lower : 5000 msl bound upper : 5000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : san
Operator	common carrier : air taxi
Make Model Name	Small Transport
Flight Phase	cruise other
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Retractable Gear
Person 1
Affiliation	company : air taxi
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 3000 flight time type : 800
ASRS Report	120100
Person 2
Affiliation	company : air taxi
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	conflict : nmac non adherence : far
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	unspecified : 450
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

From lax to san, approximately 30 NM northwest of mission bay VOR, an small aircraft Y appeared in our 2 O'clock position, 5000', 500' away. First officer spotted the small aircraft Y. I took evasive action by climbing 300' as the small aircraft Y dived. We were not alerted to its presence by san diego approach control. When we asked about the small aircraft Y position, san diego stated that there was no target painted or transponder identify of the small aircraft Y.

Original NASA ASRS Text

Title: NMAC BETWEEN COMMUTER ACFT AND LIGHT SINGLE ENGINE ACFT.

Narrative: FROM LAX TO SAN, APPROX 30 NM NW OF MISSION BAY VOR, AN SMA Y APPEARED IN OUR 2 O'CLOCK POSITION, 5000', 500' AWAY. F/O SPOTTED THE SMA Y. I TOOK EVASIVE ACTION BY CLIMBING 300' AS THE SMA Y DIVED. WE WERE NOT ALERTED TO ITS PRESENCE BY SAN DIEGO APCH CTL. WHEN WE ASKED ABOUT THE SMA Y POSITION, SAN DIEGO STATED THAT THERE WAS NO TARGET PAINTED OR XPONDER IDENT OF THE SMA Y.

Data retrieved from NASA's ASRS site as of August 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.