Student pilot with instructor on left base experiences near midair collision with aircraft on left b...

Attributes
ACN	854758
Time
Date	200910
Local Time Of Day	1201-1800
Place
Locale Reference	CMI.Airport
State Reference	IL
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Small Aircraft Low Wing 2 Eng Retractable Gear
Operating Under FAR Part	Part 91
Flight Phase	Initial Approach
Route In Use	None
Flight Plan	VFR
Aircraft 2
Make Model Name	Small Aircraft Low Wing 1 Eng Fixed Gear
Operating Under FAR Part	Part 91
Flight Phase	Initial Approach
Route In Use	None
Flight Plan	VFR
Person 1
Function	Pilot Flying Trainee
Qualification	Flight Crew Instrument Flight Crew Flight Instructor Flight Crew Multiengine Flight Crew Commercial
Experience	Flight Crew Last 90 Days 30 Flight Crew Total 290 Flight Crew Type 26
Person 2
Function	Local
Events
Anomaly	Conflict NMAC
Miss Distance	Horizontal 0 Vertical 400

Narrative:

I had just completed a go around for runway 32L and had requested a full stop landing on the parallel runway 32R. My aircraft entered a left downwind leg for runway 32L and was preparing to turn a left base leg for runway 32R. I started to turn on the base leg; but my instructor corrected me and had me continue on the downwind. On an extended left base leg for runway 32L was another aircraft; coming in from the practice area. The problem is; both aircraft were in contact with the control tower and neither aircraft was informed that the other was in the same area. As a result; the aircraft already on base passed directly under my aircraft within roughly 400 ft. The aircraft that was higher up (mine) proceeded to abruptly climb another 200 ft to avoid any possible accident. The control tower indicated only that it appeared my aircraft was turning base (which had happened but was corrected); which in terms of traffic updates shouldn't matter. Regardless of the fact that my aircraft was above the other aircraft; the control tower should have informed us of where the traffic was located so we could have found them before passing directly over them.

Original NASA ASRS Text

Title: Student pilot with instructor on left base experiences NMAC with aircraft on left base for the same runway. Tower was in contact with both aircraft but traffic was not called.

Narrative: I had just completed a go around for Runway 32L and had requested a full stop landing on the parallel Runway 32R. My aircraft entered a left downwind leg for Runway 32L and was preparing to turn a left base leg for Runway 32R. I started to turn on the base leg; but my Instructor corrected me and had me continue on the downwind. On an extended left base leg for Runway 32L was another aircraft; coming in from the practice area. The problem is; both aircraft were in contact with the Control Tower and neither aircraft was informed that the other was in the same area. As a result; the aircraft already on base passed directly under my aircraft within roughly 400 FT. The aircraft that was higher up (mine) proceeded to abruptly climb another 200 FT to avoid any possible accident. The Control Tower indicated only that it appeared my aircraft was turning base (which had happened but was corrected); which in terms of traffic updates shouldn't matter. Regardless of the fact that my aircraft was above the other aircraft; the Control Tower should have informed us of where the traffic was located so we could have found them before passing directly over them.

Data retrieved from NASA's ASRS site as of April 2012 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.

Student pilot with instructor on left base experiences near midair collision with aircraft on left base for the same runway. Tower was in contact with both aircraft but traffic was not called.