Narrative:

On dec/thu/97, 2 days prior to the event, my union representative and I were informed, in a meeting with a supervisor and the assistant manager, that we were to use pilot applied visual separation to protect aircraft from B757 wake turbulence any time less than 5 flying mi existed between the B757 and subsequent arrs. We were told that this procedure must be used whether or not the subsequent arrs will turn final prior to the B757 crossing the threshold and landing. Both of us informed management that this was a substantial change to the way we do business, in that previously we had not been separating from B757 wake turbulence after it has landed. Neither of us has ever received any training on the new procedure. Both of us were told to begin applying the procedure immediately. As a result of this instruction, while working the local 2 (pattern worker's) position the following saturday morning, I had 5 aircraft in the pattern and required all 5 of them to maintain visual separation from a B757 on approach to the parallel. On acknowledging the instruction, a C152 maneuvered to accomplish the separation. Although he was #4 in the pattern and had been instructed on who to follow, he immediately turned base leg in an effort to avoid the wake turbulence by staying ahead of the B757. He cut in between the #1 aircraft and the #2 aircraft. I believe that this incident is an unforeseen consequence of the procedure presented to me the preceding thursday. The C152 was instructed to maintain visual separation from the B757 at a point in the pattern well in advance of when he was accustomed to hearing it. His maneuver to maintain visual separation from the B757 resulted in him cutting out his traffic. This procedure needs to be researched by the facility tac team and negotiated with union. The entire controller work force needs to be trained on this.

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Original NASA ASRS Text

Title: LCL CTLR CAUTIONS A C152 ON DOWNWIND ABOUT POSSIBLE WAKE TURB FROM A B757 ON FINAL. THE C152 PLT THEN TURNS BASE LEG PREMATURELY TO AVOID THE TURB AND DISRUPTS SEQUENCING ON FINAL WITH OTHER ACFT. RPTR STATES THAT FACILITY MGMNT POLICY REQUIRES THE CTLR TO ISSUE B757 WAKE TURB ADVISORY TO ALL ACFT EVEN AFTER THE B757 HAS LANDED. THE RPTR BELIEVES THAT THE C152 TURNED EARLY BECAUSE OF THE ADVISORY.

Narrative: ON DEC/THU/97, 2 DAYS PRIOR TO THE EVENT, MY UNION REPRESENTATIVE AND I WERE INFORMED, IN A MEETING WITH A SUPVR AND THE ASSISTANT MGR, THAT WE WERE TO USE PLT APPLIED VISUAL SEPARATION TO PROTECT ACFT FROM B757 WAKE TURB ANY TIME LESS THAN 5 FLYING MI EXISTED BTWN THE B757 AND SUBSEQUENT ARRS. WE WERE TOLD THAT THIS PROC MUST BE USED WHETHER OR NOT THE SUBSEQUENT ARRS WILL TURN FINAL PRIOR TO THE B757 XING THE THRESHOLD AND LNDG. BOTH OF US INFORMED MGMNT THAT THIS WAS A SUBSTANTIAL CHANGE TO THE WAY WE DO BUSINESS, IN THAT PREVIOUSLY WE HAD NOT BEEN SEPARATING FROM B757 WAKE TURB AFTER IT HAS LANDED. NEITHER OF US HAS EVER RECEIVED ANY TRAINING ON THE NEW PROC. BOTH OF US WERE TOLD TO BEGIN APPLYING THE PROC IMMEDIATELY. AS A RESULT OF THIS INSTRUCTION, WHILE WORKING THE LCL 2 (PATTERN WORKER'S) POS THE FOLLOWING SATURDAY MORNING, I HAD 5 ACFT IN THE PATTERN AND REQUIRED ALL 5 OF THEM TO MAINTAIN VISUAL SEPARATION FROM A B757 ON APCH TO THE PARALLEL. ON ACKNOWLEDGING THE INSTRUCTION, A C152 MANEUVERED TO ACCOMPLISH THE SEPARATION. ALTHOUGH HE WAS #4 IN THE PATTERN AND HAD BEEN INSTRUCTED ON WHO TO FOLLOW, HE IMMEDIATELY TURNED BASE LEG IN AN EFFORT TO AVOID THE WAKE TURB BY STAYING AHEAD OF THE B757. HE CUT IN BTWN THE #1 ACFT AND THE #2 ACFT. I BELIEVE THAT THIS INCIDENT IS AN UNFORESEEN CONSEQUENCE OF THE PROC PRESENTED TO ME THE PRECEDING THURSDAY. THE C152 WAS INSTRUCTED TO MAINTAIN VISUAL SEPARATION FROM THE B757 AT A POINT IN THE PATTERN WELL IN ADVANCE OF WHEN HE WAS ACCUSTOMED TO HEARING IT. HIS MANEUVER TO MAINTAIN VISUAL SEPARATION FROM THE B757 RESULTED IN HIM CUTTING OUT HIS TFC. THIS PROC NEEDS TO BE RESEARCHED BY THE FACILITY TAC TEAM AND NEGOTIATED WITH UNION. THE ENTIRE CTLR WORK FORCE NEEDS TO BE TRAINED ON THIS.

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.