Near midair collision.

Attributes
ACN	203363
Time
Date	199202
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : rzs airport : sba
State Reference	CA
Altitude	msl bound lower : 8700 msl bound upper : 9000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zla tower : cvg
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Flight Phase	descent other
Flight Plan	IFR
Aircraft 2
Operator	other
Make Model Name	Medium Large Transport
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 220 flight time total : 3800
ASRS Report	203363
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	conflict : nmac non adherence : published procedure non adherence : clearance non adherence : far
Independent Detector	other controllera other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 500 vertical : 300
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation
Situations
ATC Facility	procedure or policy : unspecified

Narrative:

20 mi southeast we (light transport X) were at an altitude of 10000 ft. We requested lower from ATC. They informed us of a descent when clear of traffic off our right side. We then requested a VFR descent 'on top.' ATC granted the request. As we progressed through 9500 ft (descending 2000 FPM) in our descent, ATC informed us of traffic Y at 12 O'clock, 2 mi, and 9000 ft. We reported the traffic as 'not in sight.' no position report was given to the military aircraft Y traffic from ATC with regard to our position. We expedited our descent and within only seconds, the military aircraft came into view at 1:30-2 O'clock, same altitude. We executed evasive action and estimated the military to be within a 500 ft of a collision course. The military never reported us in sight. We believe the situation may have been avoided had we stayed IFR, and had we received more definite traffic position reporting from ATC, and had the other aircraft been alerted or informed of our position.

Original NASA ASRS Text

Title: NMAC.

Narrative: 20 MI SE WE (LTT X) WERE AT AN ALT OF 10000 FT. WE REQUESTED LOWER FROM ATC. THEY INFORMED US OF A DSCNT WHEN CLR OF TFC OFF OUR R SIDE. WE THEN REQUESTED A VFR DSCNT 'ON TOP.' ATC GRANTED THE REQUEST. AS WE PROGRESSED THROUGH 9500 FT (DSNDING 2000 FPM) IN OUR DSCNT, ATC INFORMED US OF TFC Y AT 12 O'CLOCK, 2 MI, AND 9000 FT. WE RPTED THE TFC AS 'NOT IN SIGHT.' NO POS RPT WAS GIVEN TO THE MIL ACFT Y TFC FROM ATC WITH REGARD TO OUR POS. WE EXPEDITED OUR DSCNT AND WITHIN ONLY SECS, THE MIL ACFT CAME INTO VIEW AT 1:30-2 O'CLOCK, SAME ALT. WE EXECUTED EVASIVE ACTION AND ESTIMATED THE MIL TO BE WITHIN A 500 FT OF A COLLISION COURSE. THE MIL NEVER RPTED US IN SIGHT. WE BELIEVE THE SITUATION MAY HAVE BEEN AVOIDED HAD WE STAYED IFR, AND HAD WE RECEIVED MORE DEFINITE TFC POS RPTING FROM ATC, AND HAD THE OTHER ACFT BEEN ALERTED OR INFORMED OF OUR POS.

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.