Narrative:

Small aircraft with instrument and student on cross county training flight from 5b0 to ewb. As we crossed south of pvd we were given a vector of 180 degrees by quonset approach. At this time I (instrument pilot) made visibility contact with air carrier large transport descending down to runway 34 at pvd, ahead and to our left, out of 2900'. Shortly after the controller urgently called out this traffic and instructed us to 'turn left to 360 degrees immediately.' I turned the airplane right to 360 degrees while advising ATC that a right turn was better and I was unable to comply with the left hand vector. The left vector would have placed us in the flight path of the large transport. I received no acknowledgement of my deviation, and was only advised that traffic would be passing off my right side--an large transport inbound for pvd. Nor was there any comment from the large transport, so I do not know whether they had us in sight or not. I am equally unsure whether the controller was even aware of the deviation, and unfortunately I did not press the issue. Given, however, the urgency of his voice and the imperative command he gave me, I worry that perhaps some pilots would attempt to comply with this vector, and that could result in a hazardous situation. I was not about to turn into the large transport, but my student was very confused by the dilemma as I am sure many inexperienced pilots would be--which could cause a collision hazard.

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Original NASA ASRS Text

Title: APCH CTLR GIVES WRONG EVASIVE MANEUVER TURN TO SMA IN CONFLICT WITH LGT ON APCH IN PVD ARSA.

Narrative: SMA WITH INSTR AND STUDENT ON CROSS COUNTY TRNING FLT FROM 5B0 TO EWB. AS WE CROSSED S OF PVD WE WERE GIVEN A VECTOR OF 180 DEGS BY QUONSET APCH. AT THIS TIME I (INSTR PLT) MADE VIS CONTACT WITH ACR LGT DSNDING DOWN TO RWY 34 AT PVD, AHEAD AND TO OUR LEFT, OUT OF 2900'. SHORTLY AFTER THE CTLR URGENTLY CALLED OUT THIS TFC AND INSTRUCTED US TO 'TURN LEFT TO 360 DEGS IMMEDIATELY.' I TURNED THE AIRPLANE RIGHT TO 360 DEGS WHILE ADVISING ATC THAT A RIGHT TURN WAS BETTER AND I WAS UNABLE TO COMPLY WITH THE LEFT HAND VECTOR. THE LEFT VECTOR WOULD HAVE PLACED US IN THE FLT PATH OF THE LGT. I RECEIVED NO ACKNOWLEDGEMENT OF MY DEVIATION, AND WAS ONLY ADVISED THAT TFC WOULD BE PASSING OFF MY RIGHT SIDE--AN LGT INBND FOR PVD. NOR WAS THERE ANY COMMENT FROM THE LGT, SO I DO NOT KNOW WHETHER THEY HAD US IN SIGHT OR NOT. I AM EQUALLY UNSURE WHETHER THE CTLR WAS EVEN AWARE OF THE DEVIATION, AND UNFORTUNATELY I DID NOT PRESS THE ISSUE. GIVEN, HOWEVER, THE URGENCY OF HIS VOICE AND THE IMPERATIVE COMMAND HE GAVE ME, I WORRY THAT PERHAPS SOME PLTS WOULD ATTEMPT TO COMPLY WITH THIS VECTOR, AND THAT COULD RESULT IN A HAZARDOUS SITUATION. I WAS NOT ABOUT TO TURN INTO THE LGT, BUT MY STUDENT WAS VERY CONFUSED BY THE DILEMMA AS I AM SURE MANY INEXPERIENCED PLTS WOULD BE--WHICH COULD CAUSE A COLLISION HAZARD.

Data retrieved from NASA's ASRS site as of August 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.