Narrative:

The B757 was inbound on the VOR/DME runway 22L approach. The C152 was surveying traffic and passing sebound through the final approach course of the VOR/DME runway 22L approach at 11000 ft MSL. With the B757 on final at 1800 ft MSL; with the C152 crossing right to left about 1 1/2 mi ahead; I issued traffic to the C152; which did not have the B757 in sight. I issued traffic to the B757; which had the C152 in sight; and instructed the B757 to maintain visual separation with the C152. I advised the C152 that the B757 had him in sight and would maintain visual separation. By this time; though; it was questionable as to whether radar separation was maintained prior to the application of visual separation. I had counted on the C152 seeing the larger B757 without a problem. That didn't happen; probably because the C152 was looking to the east; toward the rising sun. This; combined with limited visibility; prevented the C152 from seeing the B757. Fortunately; the B757 saw the C152 but not as soon as I had anticipated. I had kept other traffic survey aircraft clear of the final earlier that morning; but I felt I had enough time to get this C152 through final without the B757 being a factor. I was wrong. In the future; I will weigh additional factors such as reduced visibility (haze) and a rising/setting sun; before I count on a pilot seeing another aircraft.

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Original NASA ASRS Text

Title: JFK CTLR EXPERIENCED CONFLICT WITH AN IFR ACR ARR AND VFR TFC WATCH ACFT BECAUSE OF LATE USE OF VISUAL SEPARATION TECHNIQUES.

Narrative: THE B757 WAS INBOUND ON THE VOR/DME RWY 22L APCH. THE C152 WAS SURVEYING TFC AND PASSING SEBOUND THROUGH THE FINAL APCH COURSE OF THE VOR/DME RWY 22L APCH AT 11000 FT MSL. WITH THE B757 ON FINAL AT 1800 FT MSL; WITH THE C152 XING R TO L ABOUT 1 1/2 MI AHEAD; I ISSUED TFC TO THE C152; WHICH DID NOT HAVE THE B757 IN SIGHT. I ISSUED TFC TO THE B757; WHICH HAD THE C152 IN SIGHT; AND INSTRUCTED THE B757 TO MAINTAIN VISUAL SEPARATION WITH THE C152. I ADVISED THE C152 THAT THE B757 HAD HIM IN SIGHT AND WOULD MAINTAIN VISUAL SEPARATION. BY THIS TIME; THOUGH; IT WAS QUESTIONABLE AS TO WHETHER RADAR SEPARATION WAS MAINTAINED PRIOR TO THE APPLICATION OF VISUAL SEPARATION. I HAD COUNTED ON THE C152 SEEING THE LARGER B757 WITHOUT A PROB. THAT DIDN'T HAPPEN; PROBABLY BECAUSE THE C152 WAS LOOKING TO THE E; TOWARD THE RISING SUN. THIS; COMBINED WITH LIMITED VISIBILITY; PREVENTED THE C152 FROM SEEING THE B757. FORTUNATELY; THE B757 SAW THE C152 BUT NOT AS SOON AS I HAD ANTICIPATED. I HAD KEPT OTHER TFC SURVEY ACFT CLR OF THE FINAL EARLIER THAT MORNING; BUT I FELT I HAD ENOUGH TIME TO GET THIS C152 THROUGH FINAL WITHOUT THE B757 BEING A FACTOR. I WAS WRONG. IN THE FUTURE; I WILL WEIGH ADDITIONAL FACTORS SUCH AS REDUCED VISIBILITY (HAZE) AND A RISING/SETTING SUN; BEFORE I COUNT ON A PLT SEEING ANOTHER ACFT.

Data retrieved from NASA's ASRS site as of January 2009 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.