Ont local controller observed aircraft transitioning airspace without clearance.

Attributes
ACN	584371
Time
Date	200306
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : ont.airport
State Reference	CA
Altitude	msl single value : 2000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : bur.tower
Operator	general aviation : personal
Make Model Name	Cessna Aircraft Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Aircraft 2
Controlling Facilities	tower : ont.tower
Operator	common carrier : air carrier
Make Model Name	Brasilia EMB-120 All Series
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : local
Qualification	controller : radar pilot : instrument
Experience	controller limited radar : 2.5 controller time certified in position1 : 8 controller time certified in position2 : 6 flight time total : 150
ASRS Report	584371
Person 2
Affiliation	other
Function	flight crew : single pilot
Events
Anomaly	airspace violation : entry conflict : airborne less severe non adherence : published procedure non adherence : far
Independent Detector	other controllera
Resolutory Action	controller : issued advisory
Consequence	faa : investigated
Miss Distance	horizontal : 3000
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Unidented cessna transitioned through ont class C without contacting ATC. E120 was given multiple traffic calls without seeing other aircraft. Cessna passed 1/2 mi south of ont tower. Aircraft was followed via radar until he was lost due to terrain 20 northwest of ont. Aircraft also violated ATCT airspace.

Original NASA ASRS Text

Title: ONT LCL CTLR OBSERVED ACFT TRANSITIONING AIRSPACE WITHOUT CLRNC.

Narrative: UNIDENTED CESSNA TRANSITIONED THROUGH ONT CLASS C WITHOUT CONTACTING ATC. E120 WAS GIVEN MULTIPLE TFC CALLS WITHOUT SEEING OTHER ACFT. CESSNA PASSED 1/2 MI S OF ONT TWR. ACFT WAS FOLLOWED VIA RADAR UNTIL HE WAS LOST DUE TO TERRAIN 20 NW OF ONT. ACFT ALSO VIOLATED ATCT AIRSPACE.

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.