MISUNDERSTANDING OF DSCNT CLRNC CAUSES PLT DEV.

Narrative

ON FEB/FRI/95; I WAS THE CAPT (PNF) ON A BEECHJET 400 ENRTE FROM M58 TO RSW (FT MYERS; FL). ONLY THE FO AND I WERE ABOARD THE ACFT. AT ABOUT XA30Z JUST BEFORE ENTERING THE AIRSPACE OF ZMA; ZJX GAVE US A CLRNC TO 'CROSS ST. PETERSBURG (PIE) AT AND MAINTAIN FL270.' SHORTLY AFTER WE HAD BEGUN OUR DSCNT; WE WERE HANDED OFF TO ZMA. THAT CTLR THEN SAID; 'CROSS ST. PETERSBURG AT FL270; MAINTAIN FL240.' WE DSNDED OUT OF FL270; ON THE WAY TO FL240; A FEW MI AHEAD OF PIE; AND THE CTLR QUESTIONED US AS TO WHY WE WERE NOT FOLLOWING OUR CLRNC. HE THEN STATED THAT WE WERE TO HAVE REMAINED AT FL270 UNTIL PIE; AND THEN DSND TO FL240. WE ASKED WHAT HE WANTED US TO DO. WHEN THERE WAS NO REPLY; WE ASKED; 'DO YOU WANT US TO CLB BACK TO FL270?' AFTER A LONG PAUSE; HE SAID SOMETHING TO THE EFFECT; 'THERE IS NO PROB AT ALL; MAINTAIN FL240 AND CONTACT ZMA; FREQ XXX.XX.' BOTH THE FO AND I HAD NO QUESTION THAT THE LATTER CLRNC MEANT THAT WE HAD TO BE AT OR BELOW FL270 (A REITERATION OF JACKSONVILLE'S XING RESTR); ON OUR WAY TO FL240; BY THE TIME WE CROSSED PIE. WE DID NOT QUESTION OR DISCUSS IT; OTHER THAN TO FOLLOW OUR STANDARD; ACR X-DEVELOPED ALT REMINDER PROC; SIMPLY BECAUSE WE WERE PERFECTLY CLR IN OUR OWN MINDS ABOUT WHAT THE CTLR HAD INTENDED FOR US TO DO. IN 34 YRS OF FLYING; WITH CONSIDERABLE EXPERIENCE AS A FAR PART 121 ACR PLT; I HAVE NEVER HAD A CLRNC THAT; IN RETROSPECT; SEEMED MORE AMBIGUOUS THAN THE LATTER ONE; ABOVE. THE FO LIKEWISE AGREED WITH THIS ASSESSMENT. IF THE CTLR HAD WANTED US TO CROSS PIE AT EXACTLY FL270; HE SHOULD HAVE EXPLICITLY STATED THIS; AND NOT GIVEN THE CLRNC TO DSND TO FL240 AT THE SAME TIME. THE FO AND I HAD PERIODIC DISCUSSIONS ABOUT THIS INCIDENT THROUGHOUT THE REMAINDER OF THE DAY; AND WE BOTH AGREED THAT WE HAD DONE EXACTLY AS WE HAD BEEN CLRED; AS STATED BY THE CTLR. WE BOTH FELT THAT THE CTLR SHOULD HAVE BEEN MUCH MORE SPECIFIC IF HE WISHED TO CONVEY A CLRNC THAT; AS WAS APPARENT AFTER THE FACT; WAS NON-STANDARD (BASED UPON OUR ACCUMULATED FLT EXPERIENCE). ON FEB/MON/95; I CALLED THE QUALITY ASSURANCE DESK AT MIAMI ARTCC; AND DISCUSSED THIS INCIDENT WITH A SUPVR. HE SAID THAT NO TFC CONFLICT HAD OCCURRED; AND THAT NO ADMINISTRATIVE ACTION HAD BEEN TAKEN. FROM MY DESCRIPTION OF THE EVENT; HE AGREED THAT THE CLRNC WE RECEIVED COULD HAVE BEEN EASILY MISINTERPRETED; AND HE VOLUNTEERED TO CHK THE TAPE RECORDINGS OF THE RADIO EXCHANGES TO GET A CLR PICTURE OF EXACTLY WHAT HAD TRANSPIRED. IN A TELEPHONE DISCUSSION ON FEB/THUR/95; SAID THAT HE HAD LISTENED TO THE TAPES THAT MORNING; AND CONFIRMED THE ACCURACY OF THE ACCOUNT STATED ABOVE. HE AGAIN STATED THAT OUR INTERP OF THE CLRNC WAS QUITE REASONABLE; UNDER THE CIRCUMSTANCES. 1 VERY IRONIC; AND PERHAPS OMINOUS; RESULT OF MY TAKING THE TIME TO FOLLOW UP WITH MIAMI ARTCC ON THIS PROB: THEY SAID THAT BECAUSE MY FO AND I WERE FILING ASRS RPTS; HE WOULD CONSIDER FILING A PLT DEV RPT TO AVOID REPERCUSSIONS AT THE CTR (EVEN THOUGH SOME 7 DAYS HAD TRANSPIRED; AFTER AN OCCURRENCE THAT EVERYONE AGREED HAD CAUSED NO TFC CONFLICT). THEY WERE OF THE STRONG BELIEF THAT THE 'ANONYMITY' OF THE RPT WOULD NOT PREVENT A FOLLOW-UP ACTION AT THE CTR - WITH NEGATIVE OVERTONES - BEING TAKEN AS A DIRECT RESULT OF THE ASRS RPT. IT WOULD INDEED BE AN UNINTENDED CONSEQUENCE OF THE WHOLE ASRS SYS IF THE FO AND I WERE TO BE 'VIOLATED' AS A DIRECT RESULT OF OUR CONSCIENTIOUSLY FOLLOWING UP ON THE OCCURRENCE; AND THEN LOSE OUR IMMUNITY FOR A 5 YR PERIOD. OUR 'DEV' - IF IN FACT IT COULD BE CALLED THAT - WAS ANYTHING BUT WILLFUL; AND WE ARE ABSOLUTELY CONVINCED THAT A LARGE PERCENTAGE OF PROFESSIONAL PLTS WOULD HAVE DONE EXACTLY THE SAME THING AS WE DID; GIVEN THE EXACT SEQUENCE OF EVENTS.