A C152 pilot experienced an near midair collision at vnc.

Attributes
ACN	582001
Time
Date	200305
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : vnc.airport
State Reference	FL
Altitude	msl single value : 1030
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Cessna 152
Operating Under FAR Part	Part 91
Flight Phase	descent : approach
Route In Use	approach : traffic pattern
Flight Plan	VFR
Aircraft 2
Operator	general aviation : instructional
Make Model Name	Cessna 152
Operating Under FAR Part	Part 91
Flight Phase	climbout : takeoff descent : approach
Route In Use	approach : traffic pattern
Flight Plan	VFR
Person 1
Affiliation	other
Function	flight crew : single pilot oversight : pic
Qualification	pilot : commercial
Experience	flight time last 90 days : 16 flight time total : 220 flight time type : 150
ASRS Report	582001
Person 2
Affiliation	other
Function	instruction : instructor
Events
Anomaly	conflict : nmac non adherence : published procedure other spatial deviation
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 100 vertical : 0
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

I was practicing touch and goes and was on downwind for runway 22 at almost midpoint when the second craft executed a right turn for downwind for the same runway. He didn't announce until after the turn. I tried to avoid a collision. At about this time, the 2ND craft announced seeing traffic (me). I turned right and climbed to avoid him. When I spoke to the pilot on the ground, I found out there was an instructor with him. I think the instructor used very poor judgement by allowing the student to try and enter the pattern. The instructor acknowledged seeing me, but didn't want to execute a 180 degree or 360 degree turn away from me. He (they) grossly misjudged distance, separation and timing. I think the factors involved were inattentiveness and being lazy.

Original NASA ASRS Text

Title: A C152 PLT EXPERIENCED AN NMAC AT VNC.

Narrative: I WAS PRACTICING TOUCH AND GOES AND WAS ON DOWNWIND FOR RWY 22 AT ALMOST MIDPOINT WHEN THE SECOND CRAFT EXECUTED A R TURN FOR DOWNWIND FOR THE SAME RWY. HE DIDN'T ANNOUNCE UNTIL AFTER THE TURN. I TRIED TO AVOID A COLLISION. AT ABOUT THIS TIME, THE 2ND CRAFT ANNOUNCED SEEING TFC (ME). I TURNED R AND CLBED TO AVOID HIM. WHEN I SPOKE TO THE PLT ON THE GND, I FOUND OUT THERE WAS AN INSTRUCTOR WITH HIM. I THINK THE INSTRUCTOR USED VERY POOR JUDGEMENT BY ALLOWING THE STUDENT TO TRY AND ENTER THE PATTERN. THE INSTRUCTOR ACKNOWLEDGED SEEING ME, BUT DIDN'T WANT TO EXECUTE A 180 DEG OR 360 DEG TURN AWAY FROM ME. HE (THEY) GROSSLY MISJUDGED DISTANCE, SEPARATION AND TIMING. I THINK THE FACTORS INVOLVED WERE INATTENTIVENESS AND BEING LAZY.

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.