A C172 PLT PENETRATED CLASS B WITHOUT A CLRNC AND CONFLICTED WITH BE20 ON APCH. NO RESPONSE TIME.

Narrative

WHILE DOING THE VOR DME-A APCH TO TETERBORO; NJ; ON SEP/TUE/95 WE JUST PASSED THE WANES INTXN AT 3000 FT MSL. I WAS LOOKING DOWN AT THE APCH CHART TO SEE WHAT THE NEXT FIX WAS. WHEN I LOOKED UP AGAIN I SAW A CESSNA 100 SERIES ACFT RIGHT IN FRONT OF MY ACFT AT APPROX THE SAME ALT AND DSNDING. JUST AS THE OTHER ACFT WENT UNDER MY L WING NY APCH CALLED THE TFC AT LESS THAN 1 MI. AFTER TALKING TO APCH ABOUT THIS WE LOST OUR CHAIN OF THOUGHT AND AM NOT SURE THAT WE PASSED CLIFO INTXN AT 2000 FT. SUPPLEMENTAL INFO FROM ACN 315859: I WAS OCCUPYING R SEAT OF A KING AIR BE2H PERFORMING PNF DUTIES. MY ATTN WAS DIVIDED BOTH INSIDE AND OUT OF THE COCKPIT; AS WAS THE PF CHKING THE APCH PLATE FIXES AND ALTS. PF EXCLAIMED 'OH; MY GOSH!' I LOOKED UP TO SEE A LIGHT COLORED C172 (?) DSNDING BELOW AND JUST OUTBOARD OF OUR L WINGTIP. APCH CALLED TFC JUST IMMEDIATELY PRIOR TO THE PF'S SIGHTING IT; BUT WE WOULD HAVE HAD LITTLE TIME TO REACT TO HIS CALL. HE IMMEDIATELY APOLOGIZED AND ASKED THE ACFT'S ALT; WE ESTIMATED 2950 FT TO 3000 FT. WE WERE CONSEQUENTLY SO DISTRAUGHT THAT APCH OR TWR HAD TO ADMONISH US TO DSND TO MANDATORY ALT OF 2000 FT MSL AT 'CLIFO' INTXN. PERHAPS GREATER FAMILIARITY WITH THE APCH MIGHT HAVE ALLOWED US TO SPEND MORE TIME OUTSIDE OF COCKPIT; BUT WE HAD JUST PASSED A WAYPOINT AND WERE CHKING THE NEXT PHASE AND SETTING THE ALT ALERTER. TWO HEADS IN THE COCKPIT AT THE SAME TIME DIDN'T HELP.