ALT BUST.

Narrative

IFR FLT PLAN VFR CONDITIONS 41000 FT STJ TO LIT. 90 MI NW OF LIT CLRNC RECEIVED 'LEAR; DSND TO FL270 PLT'S DISCRETION 240.' WHILE IN DSCNT; MEP CTLR SAID 'LEAR; LET'S MAKE IT PLT'S DISCRETION 290.' MY COPLT REPLIED 'PLT'S DISCRETION 290.' BOTH OF US THINKING CTLR WAS BEING HELPFUL BY RELIEVING THE 270 RESTRICTION; LEFT 24000 FT IN ALT ALERT AND CONTINUED DSCNT. MEP CTLR GAVE US A 20 DEG L TURN. ACR Y ANNOUNCED HE WAS DEVIATING DUE (I THINK) RA. CTR SAID LEAR JET IS AT 290. I LOOKED AT ALTIMETER; IT SHOWED 28500 FT. NOW KNOWING CTR THOUGHT I WAS AT 290; STARTED CLB TO FL290 AND I CALLED CTR STATING 'I THOUGHT MY CLRNC LIMIT WAS 240.' CTLR ASKED ACR Y HOW MUCH HE HAD DEVIATED. ACR 'ABOUT 100 FT.' AFTER LNDG AT LIT; TWR ASKED US TO CALL APCH CTL WHEN WE PARKED. CALLED; APCH ANSWERED ADVISING ME ZME HAD CALLED TO SAY THEY WERE INVESTIGATING A PLTDEV INVOLVING US. IF I WANTED MORE INFO HE GAVE ME ZME'S PHONE NUMBER. I CALLED AND TALKED WITH MR. X. HE SAID THEY HAD PULLED THE TAPES BUT HADN'T REVIEWED THEM YET. I COULD CALL BACK IN 1 HR; WHICH I DID. MR. X WASN'T AVAILABLE; BUT LADY WHO ANSWERED SAID MY CLRNC WAS 290 AND THEY WOULD BE PROCESSING VIOLATION ACTION. NATURALLY; I'VE THOUGHT ABOUT THIS A GREAT DEAL AND FEEL MOST PLTS WOULD HAVE THOUGHT THEIR CLRNC WAS FL240. AS TO HOW THIS COULD HAVE BEEN AVOIDED? IF MEP CTLR USED PROPER PHRASEOLOGY THE CLRNC WOULD HAVE BEEN MUCH CLEARER. 'TFC AT 280 MAINTAIN 290.' 'CANCEL PREVIOUS CLRNC MAINTAIN 290.' 'MAINTAIN 290' OR IF WE HAD INSTALLED A TCA D OR TCASII WHICH WOULD HAVE MADE ME AWARE OF THE 280 TFC OR BE CLAIRVOYANT!