Close proximity GA-small aircraft air carrier-light transport 14 NM east of sjc.

Attributes
ACN	154439
Time
Date	199008
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : sjc
State Reference	CA
Altitude	msl bound lower : 5000 msl bound upper : 5200
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zoa
Operator	general aviation : personal
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Fixed Gear
Flight Phase	cruise other
Route In Use	enroute : direct
Flight Plan	None
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Light Transport
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Experience	flight time last 90 days : 23 flight time total : 115 flight time type : 23
ASRS Report	154439
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : nmac non adherence : far
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	Other
Miss Distance	horizontal : 0 vertical : 200
Supplementary
Primary Problem	Flight Crew Human Performance

Narrative:

I was under ATC control flight following VFR sacramento to monterey, ca. Requested by ATC to stay at 6500' told ATC will descend to 6000' MSL to avoid clouds overhead. Ceiling lowered and I descended to 5200' west/O telling ATC. They notified me that a large commuter aircraft had passed below at 5000' MSL. By monitoring communications I knew the other aircraft had me in sight before reaching my position. After event ATC told me I had changed altitude west/O notifying them. It was my error to change altitude west/O telling ATC. No fault found with ATC. It was my error. WX (clouds) was a significant factor in this.

Original NASA ASRS Text

Title: CLOSE PROX GA-SMA ACR-LTT 14 NM EAST OF SJC.

Narrative: I WAS UNDER ATC CTL FLT FOLLOWING VFR SACRAMENTO TO MONTEREY, CA. REQUESTED BY ATC TO STAY AT 6500' TOLD ATC WILL DSND TO 6000' MSL TO AVOID CLOUDS OVERHEAD. CEILING LOWERED AND I DSNDED TO 5200' W/O TELLING ATC. THEY NOTIFIED ME THAT A LARGE COMMUTER ACFT HAD PASSED BELOW AT 5000' MSL. BY MONITORING COMS I KNEW THE OTHER ACFT HAD ME IN SIGHT BEFORE REACHING MY POS. AFTER EVENT ATC TOLD ME I HAD CHANGED ALT W/O NOTIFYING THEM. IT WAS MY ERROR TO CHANGE ALT W/O TELLING ATC. NO FAULT FOUND WITH ATC. IT WAS MY ERROR. WX (CLOUDS) WAS A SIGNIFICANT FACTOR IN THIS.

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.