Narrative:

The pilot of aircraft #2 alleges a lack of adequate separation during the cruise portion of the flight. He claims that he was required to take evasive action. Based upon a brief discussion with the pilot of aircraft #2 at the conclusion of the flight, both aircraft were flying from ack to bed. I believe that aircraft #2 departed ack about 5 mins prior to my departure. I flew a more westwardly track than a direct route to avoid substantial overwater night operations. I monitored cape approach but was not using flight following. About 20 mins into the flight, while descending from 4500 ft to 3000 ft, I observed that I was overtaking another aircraft about 2 mi ahead. I set up to pass that aircraft on his right, but the aircraft made a right turn to a northerly heading. I then turned left back to my original northwest heading and away from aircraft #2. I noticed aircraft #2 then make a left heading change. I then decided not to pass aircraft #2 and positioned the planes so that aircraft #2 was at my 1-2 O'clock position, about 2 mi away. This position allowed both myself and my copilot a good view of aircraft #2. I also engaged my autoplt to minimize any heading changes I might inadvertently make. During the next 10 mins, our 2 aircraft would move apart and then closer together, varying between 1-2 mi. A few times I changed my course to the left to increase the distance between us. Aircraft #2 continued to make small left and right heading changes. At one point, aircraft #2 made a right turn and left the area. Based upon my discussion with the pilot of aircraft #2, I believe that a contributing factor was that he was using flight following from ATC. When I initially started to pass his plane on the right, he made a turn to the right. When I moved back to the left, he made a turn to the left. He made these heading changes based on advice from ATC. Each time, however, we had made a heading change a min before. I believe that ATC, in their attempt to avoid a potential conflict, was vectoring the plane based on our previous position and track. Another contributing factor was my failure to use flight following. At this segment of the flight, I was no longer monitoring the same ATC controller as aircraft #2. The controller was unable to determine if I had aircraft #2 in view and was able to maintain visual separation. To be safe, the controller advised aircraft #2, after 10 mins, to make a right turn away from our position. At no point after the initial course changes was there the potential for a collision. We had aircraft #2 in view at all times and had widened our course to the left several times to allow for more space between the aircraft.

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Original NASA ASRS Text

Title: PLT OF A C182 ON A NIGHT VFR FLT, NOTICED A C172 ON SIMILAR COURSE MAKING TURNS TOWARD HIS FLT PATH EACH TIME HE CHANGED HDGS TO ASSURE SEPARATION. POSTFLT DISCUSSION WITH THE PLT OF THE C172 DISCLOSED THAT HE WAS GETTING FLT FOLLOWING FROM ARTCC CTLR WHICH HAD DIRECTED HIM TO TURN TO ASSURE SEPARATION.

Narrative: THE PLT OF ACFT #2 ALLEGES A LACK OF ADEQUATE SEPARATION DURING THE CRUISE PORTION OF THE FLT. HE CLAIMS THAT HE WAS REQUIRED TO TAKE EVASIVE ACTION. BASED UPON A BRIEF DISCUSSION WITH THE PLT OF ACFT #2 AT THE CONCLUSION OF THE FLT, BOTH ACFT WERE FLYING FROM ACK TO BED. I BELIEVE THAT ACFT #2 DEPARTED ACK ABOUT 5 MINS PRIOR TO MY DEP. I FLEW A MORE WESTWARDLY TRACK THAN A DIRECT RTE TO AVOID SUBSTANTIAL OVERWATER NIGHT OPS. I MONITORED CAPE APCH BUT WAS NOT USING FLT FOLLOWING. ABOUT 20 MINS INTO THE FLT, WHILE DSNDING FROM 4500 FT TO 3000 FT, I OBSERVED THAT I WAS OVERTAKING ANOTHER ACFT ABOUT 2 MI AHEAD. I SET UP TO PASS THAT ACFT ON HIS R, BUT THE ACFT MADE A R TURN TO A NORTHERLY HDG. I THEN TURNED L BACK TO MY ORIGINAL NW HDG AND AWAY FROM ACFT #2. I NOTICED ACFT #2 THEN MAKE A L HDG CHANGE. I THEN DECIDED NOT TO PASS ACFT #2 AND POSITIONED THE PLANES SO THAT ACFT #2 WAS AT MY 1-2 O'CLOCK POS, ABOUT 2 MI AWAY. THIS POS ALLOWED BOTH MYSELF AND MY COPLT A GOOD VIEW OF ACFT #2. I ALSO ENGAGED MY AUTOPLT TO MINIMIZE ANY HDG CHANGES I MIGHT INADVERTENTLY MAKE. DURING THE NEXT 10 MINS, OUR 2 ACFT WOULD MOVE APART AND THEN CLOSER TOGETHER, VARYING BTWN 1-2 MI. A FEW TIMES I CHANGED MY COURSE TO THE L TO INCREASE THE DISTANCE BTWN US. ACFT #2 CONTINUED TO MAKE SMALL L AND R HDG CHANGES. AT ONE POINT, ACFT #2 MADE A R TURN AND LEFT THE AREA. BASED UPON MY DISCUSSION WITH THE PLT OF ACFT #2, I BELIEVE THAT A CONTRIBUTING FACTOR WAS THAT HE WAS USING FLT FOLLOWING FROM ATC. WHEN I INITIALLY STARTED TO PASS HIS PLANE ON THE R, HE MADE A TURN TO THE R. WHEN I MOVED BACK TO THE L, HE MADE A TURN TO THE L. HE MADE THESE HDG CHANGES BASED ON ADVICE FROM ATC. EACH TIME, HOWEVER, WE HAD MADE A HDG CHANGE A MIN BEFORE. I BELIEVE THAT ATC, IN THEIR ATTEMPT TO AVOID A POTENTIAL CONFLICT, WAS VECTORING THE PLANE BASED ON OUR PREVIOUS POS AND TRACK. ANOTHER CONTRIBUTING FACTOR WAS MY FAILURE TO USE FLT FOLLOWING. AT THIS SEGMENT OF THE FLT, I WAS NO LONGER MONITORING THE SAME ATC CTLR AS ACFT #2. THE CTLR WAS UNABLE TO DETERMINE IF I HAD ACFT #2 IN VIEW AND WAS ABLE TO MAINTAIN VISUAL SEPARATION. TO BE SAFE, THE CTLR ADVISED ACFT #2, AFTER 10 MINS, TO MAKE A R TURN AWAY FROM OUR POS. AT NO POINT AFTER THE INITIAL COURSE CHANGES WAS THERE THE POTENTIAL FOR A COLLISION. WE HAD ACFT #2 IN VIEW AT ALL TIMES AND HAD WIDENED OUR COURSE TO THE L SEVERAL TIMES TO ALLOW FOR MORE SPACE BTWN THE ACFT.

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.