VFR overflt conflicted with a departing air carrier.

Attributes
ACN	120781
Time
Date	198908
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : oak
State Reference	CA
Altitude	msl bound lower : 1300 msl bound upper : 2000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : oak
Operator	general aviation : personal
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	cruise other
Flight Plan	None
Aircraft 2
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 departure sid : sid
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : local
Qualification	controller : non radar
Experience	controller non radar : 8 flight time last 90 days : 0 flight time total : 110 flight time type : 110
ASRS Report	120781
Person 2
Affiliation	government : faa
Function	controller : local
Qualification	controller : developmental
Events
Anomaly	non adherence : clearance other spatial deviation
Independent Detector	other controllera
Resolutory Action	other
Consequence	Other
Miss Distance	horizontal : 0 vertical : 700
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

VFR pilot entered arsa prior to establishing radio contact with ATC. Radar identified 4 southeast of the airport and instructed to cross the approach end of runway 29 at 2000' for transitioning to napa. Target observed approximately 2 southeast of runway at 2000 heading for approach end of runway. My trainee went on to other tasks. An air carrier departure was changed to TRACON's frequency, then trainee's attention returned to transitioning overflt. (Alpha numeric data tag had dropped off and target had merged with runway return.) overflt had not followed instruments, and data tag reacquired with aircraft approximately 1 1/2 west of runway 29 crossing the departure corridor from left to right at 2000. Departure aircraft was same location at 1300.

Original NASA ASRS Text

Title: VFR OVERFLT CONFLICTED WITH A DEPARTING ACR.

Narrative: VFR PLT ENTERED ARSA PRIOR TO ESTABLISHING RADIO CONTACT WITH ATC. RADAR IDENTIFIED 4 SE OF THE ARPT AND INSTRUCTED TO CROSS THE APCH END OF RWY 29 AT 2000' FOR TRANSITIONING TO NAPA. TARGET OBSERVED APPROX 2 SE OF RWY AT 2000 HDG FOR APCH END OF RWY. MY TRAINEE WENT ON TO OTHER TASKS. AN AIR CARRIER DEP WAS CHANGED TO TRACON'S FREQ, THEN TRAINEE'S ATTN RETURNED TO TRANSITIONING OVERFLT. (ALPHA NUMERIC DATA TAG HAD DROPPED OFF AND TARGET HAD MERGED WITH RWY RETURN.) OVERFLT HAD NOT FOLLOWED INSTRUMENTS, AND DATA TAG REACQUIRED WITH ACFT APPROX 1 1/2 W OF RWY 29 XING THE DEP CORRIDOR FROM LEFT TO RIGHT AT 2000. DEP ACFT WAS SAME LOCATION AT 1300.

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.