Narrative:

On the visual approach to teb, tower advised us of our traffic to follow and also a single engine cessna transitioning the air traffic area at 1300 ft in our 2 O'clock position. I idented the traffic and pointed it out to the captain who was flying. He confirmed the traffic in sight. So I started looking for our traffic to follow. The single engine cessna was approximately 2 mi ahead, right to left, across our downwind leg. As we converged closer, tower again advised us of the traffic (the cessna) and I reconfirmed with the captain that he had it in sight. At this time we were cleared to land and I was distracted by the landing checklist. Tower again called the cessna traffic to us as we were turning base. I looked up and spotted him at 12:30 O'clock position and approximately the same altitude. Seeing a potential conflict I told the captain 'XXX you're too close!' while pointing at the traffic. At this time the captain steepened the turn and increased the descent. I doubt that we would have collided without the evasive action, but it would have been close. Several things contributed to this incident: 1) the usual crowded new york airspace. 2) a slow moving aircraft transitioning the traffic area at pattern altitude. 3) the difficulty in spotting aircraft against the city lights. Looking for the traffic to follow. Differentiating between targets. (There were at least 2 other targets in visual area of the single engine cessna.) 4) habit patterns on when and where to fly the traffic pattern (ie, turning base at the same exact spot). 5) mild complacency. 6) high cockpit workloads in the pattern. 7) change in sleep pattern (it was the first night back to work after the wkend). The best thing that can be done to prevent sits like this is to stay heads up and fly defensively.

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Original NASA ASRS Text

Title: POTENTIAL CONFLICT LTSS. THE FLC HAD THE TRANSITIONING ACFT IN SIGHT, BUT THE CAPT LOST SITUATIONAL AWARENESS AND ALMOST HIT IT.

Narrative: ON THE VISUAL APCH TO TEB, TWR ADVISED US OF OUR TFC TO FOLLOW AND ALSO A SINGLE ENG CESSNA TRANSITIONING THE ATA AT 1300 FT IN OUR 2 O'CLOCK POS. I IDENTED THE TFC AND POINTED IT OUT TO THE CAPT WHO WAS FLYING. HE CONFIRMED THE TFC IN SIGHT. SO I STARTED LOOKING FOR OUR TFC TO FOLLOW. THE SINGLE ENG CESSNA WAS APPROX 2 MI AHEAD, R TO L, ACROSS OUR DOWNWIND LEG. AS WE CONVERGED CLOSER, TWR AGAIN ADVISED US OF THE TFC (THE CESSNA) AND I RECONFIRMED WITH THE CAPT THAT HE HAD IT IN SIGHT. AT THIS TIME WE WERE CLRED TO LAND AND I WAS DISTRACTED BY THE LNDG CHKLIST. TWR AGAIN CALLED THE CESSNA TFC TO US AS WE WERE TURNING BASE. I LOOKED UP AND SPOTTED HIM AT 12:30 O'CLOCK POS AND APPROX THE SAME ALT. SEEING A POTENTIAL CONFLICT I TOLD THE CAPT 'XXX YOU'RE TOO CLOSE!' WHILE POINTING AT THE TFC. AT THIS TIME THE CAPT STEEPENED THE TURN AND INCREASED THE DSCNT. I DOUBT THAT WE WOULD HAVE COLLIDED WITHOUT THE EVASIVE ACTION, BUT IT WOULD HAVE BEEN CLOSE. SEVERAL THINGS CONTRIBUTED TO THIS INCIDENT: 1) THE USUAL CROWDED NEW YORK AIRSPACE. 2) A SLOW MOVING ACFT TRANSITIONING THE TFC AREA AT PATTERN ALT. 3) THE DIFFICULTY IN SPOTTING ACFT AGAINST THE CITY LIGHTS. LOOKING FOR THE TFC TO FOLLOW. DIFFERENTIATING BTWN TARGETS. (THERE WERE AT LEAST 2 OTHER TARGETS IN VISUAL AREA OF THE SINGLE ENG CESSNA.) 4) HABIT PATTERNS ON WHEN AND WHERE TO FLY THE TFC PATTERN (IE, TURNING BASE AT THE SAME EXACT SPOT). 5) MILD COMPLACENCY. 6) HIGH COCKPIT WORKLOADS IN THE PATTERN. 7) CHANGE IN SLEEP PATTERN (IT WAS THE FIRST NIGHT BACK TO WORK AFTER THE WKEND). THE BEST THING THAT CAN BE DONE TO PREVENT SITS LIKE THIS IS TO STAY HEADS UP AND FLY DEFENSIVELY.

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.