UNAUTH RWY XING BY SUPPLEMENTAL CARRIER.

Narrative

FOR 6 YRS; WHEN TAXIING FROM OUR RAMPS TO RWY 29 AT SFE THE ONLY WAY TO GET THERE WAS TO TAXI ACROSS 29 AND TURN R ON TAXIWAY 'C'. WE WERE STOPPED BEHIND 2 WDB ACFT. ALL OF US WAITING TO CROSS THE RWY. THE WDBS WERE CLRED TO CROSS; AND MY COPLT CALLED GND TO SEE IF THEY WANTED US TO FOLLOW THE WDBS ACROSS THE RWY. THE ANSWER WAS 'YES; FOLLOW WDB TYPE TURN R ON M AND TAXI TO RWY 29.' AFTER XING THE RWY; GND CALLED AND INFORMED US THAT M WAS THE NEW TAXIWAY ON THE OTHER SIDE OF THE RWY AND HAD BEEN OPEN 3 WKS! (SURE ENOUGH; A NICE SHINY NEW TAXIWAY THAT WE WERE SUPPOSED TO BE ON). I HAD KNOWN THAT THERE WAS CONSTRUCTION OF NEW TAXIWAYS AND RWYS UNDERWAY; BUT NO INFO ABOUT THEM BEING OPEN WAS AVAILABLE (I CHKED). I HAVE NO IDEA HOW TO STOP THIS TYPE OF INCURSION. I WAS SO INVOLVED IN 'FOLLOW WDB TURN R;' WHICH I WAS USED TO; THAT I MISSED 'ON TAXIWAY M.' THAT MADE NO SENSE (UNTIL A MIN LATER). CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO. RPTR SAYS THAT NEW ARPT DIAGRAM SHOWING TAXIWAY M APPEARED IN COMMERCIAL CHARTS IN SECOND WK OF 2/92. BEFORE INCIDENT THEY HAD RECEIVED NO INFO ON OPENING OF TAXIWAY. FLT MGR IN COCKPIT HEARD CLRNC TO RWY 29 AND JUMPED OUT OF SEAT TO CHK WITH SO ON LEGALITY OF USING THAT RWY. THIS WAS AT SAME TIME THAT GND CTLR WAS SAYING 'TURN R ON M AND TAXI TO RWY 29.' NEITHER PIC (PF) OR FO HEARD THAT PART OF CLRNC. ALSO SAID THAT ABOUT THAT TIME THEY WERE STARTING THE 2 OUTBOARD ENGS AND RUNNING ENG START CHKLISTS. LOT OF NOISE AND DISTRS IN COCKPIT.