Narrative:

While on a night training flight, my student and I were returning to our base airport of 06C from mdw via transition through cgx. After clearing mdw, we proceeded to contact cgx tower and request transition from south to north at 1700 ft. Our request was approved and we proceeded to follow a course approximately 3/4 mi east of cgx runway 36/18. Shortly thereafter, another aircraft contacted cgx tower from the north, inbound for landing. The tower controller instructed the inbound aircraft to enter right traffic for runway 36 and informed him of traffic off his left side. The pilot acknowledged his instructions and reported traffic not in sight. The controller then reported to us traffic off our left side to which we responded, in sight. My initial assessment of the situation was that if both aircraft proceeded on their present courses, there should be no conflict. As we approached the other aircraft, we realized it was moving across our course from left to right. We responded with a left 30 degree bank turn to avoid collision and the aircraft passed off our right side by approximately 300 ft. Upon later analysis of the circumstances which led to the near miss, I realize that we could have better anticipated the intentions of the other aircraft and made corrective action sooner. Other actions which could have dissolved the situation sooner are increased communication on all parts (between aircraft and controller).

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Original NASA ASRS Text

Title: NMAC BTWN AN SEL SMA ON A NIGHT TRAINING FLT TRANSITING THROUGH CLASS D AIRSPACE AND ANOTHER ACFT CLRED ON THE DOWNWIND LEG FROM THE OPPOSITE DIRECTION.

Narrative: WHILE ON A NIGHT TRAINING FLT, MY STUDENT AND I WERE RETURNING TO OUR BASE ARPT OF 06C FROM MDW VIA TRANSITION THROUGH CGX. AFTER CLRING MDW, WE PROCEEDED TO CONTACT CGX TWR AND REQUEST TRANSITION FROM S TO N AT 1700 FT. OUR REQUEST WAS APPROVED AND WE PROCEEDED TO FOLLOW A COURSE APPROX 3/4 MI E OF CGX RWY 36/18. SHORTLY THEREAFTER, ANOTHER ACFT CONTACTED CGX TWR FROM THE N, INBOUND FOR LNDG. THE TWR CTLR INSTRUCTED THE INBOUND ACFT TO ENTER R TFC FOR RWY 36 AND INFORMED HIM OF TFC OFF HIS L SIDE. THE PLT ACKNOWLEDGED HIS INSTRUCTIONS AND RPTED TFC NOT IN SIGHT. THE CTLR THEN RPTED TO US TFC OFF OUR L SIDE TO WHICH WE RESPONDED, IN SIGHT. MY INITIAL ASSESSMENT OF THE SIT WAS THAT IF BOTH ACFT PROCEEDED ON THEIR PRESENT COURSES, THERE SHOULD BE NO CONFLICT. AS WE APCHED THE OTHER ACFT, WE REALIZED IT WAS MOVING ACROSS OUR COURSE FROM L TO R. WE RESPONDED WITH A L 30 DEG BANK TURN TO AVOID COLLISION AND THE ACFT PASSED OFF OUR R SIDE BY APPROX 300 FT. UPON LATER ANALYSIS OF THE CIRCUMSTANCES WHICH LED TO THE NEAR MISS, I REALIZE THAT WE COULD HAVE BETTER ANTICIPATED THE INTENTIONS OF THE OTHER ACFT AND MADE CORRECTIVE ACTION SOONER. OTHER ACTIONS WHICH COULD HAVE DISSOLVED THE SIT SOONER ARE INCREASED COM ON ALL PARTS (BTWN ACFT AND CTLR).

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.