DC9-40 ACFT WITH TAXI INSTRUCTIONS TO HOLD SHORT OF TXWY FOR ANOTHER ACFT. FLC DIDN'T CLARIFY WHERE THE ACFT WAS COMING FROM NOR DID GND CTLR GIVE CLR DIRECTIONS.

Narrative

CAPT WAS TAXIING ACFT NBOUND ON TXWY Y. WE HAD JUST SWITCHED GND CTLRS FROM 119.45 TO 121.8; HAVING HELD SHORT OF TXWY K WHILE FACING WBOUND ON TXWY V. NEW GND CTLR'S (121.8) INSTRUCTIONS WERE TO TAXI N ON TXWY Y; HOLD SHORT OF TXWY Y12; AND WAIT FOR THE AIRBUS L TO R; TXWY Y IS A NS TXWY. WE ASSUMED THE AIRBUS WOULD BE ON THE PARALLEL TXWY K; PROCEEDING S; AND THAT WE WERE TO CONTINUE THROUGH (NBOUND) TXWY Y12 AFTER THE AIRBUS HAD PASSED OFF OF OUR R. THE CTLR DID NOT TELL US THE AIRBUS WAS COMING FROM THE HANGAR; ON THE OTHER SIDE OF RWY 3L/21R; A POS 90 DEGS TO OUR L. AS WE APCHED TXWY Y12 WE DID NOT SEE THE AIRBUS IN OUR NORMAL AREA OF VISION (SLIGHTLY L; DIRECTLY AHEAD; OR SLIGHTLY R); AND WE ASSUMED THE AIRBUS HAD ALREADY PASSED OFF OF OUR R; N TO S ON TXWY K. WE PROCEEDED INTO TXWY Y12 NBOUND. ABOUT 1/2 WAY INTO TXWY Y12; THE CTLR STATED THAT WE WERE SUPPOSED TO HOLD SHORT OF TXWY Y12; BUT NOW TO EXPEDITE THROUGH TXWY Y12 AND CONTINUE. WE LOOKED AT EACH OTHER IN SURPRISE; TAXIED THROUGH; AND I ASKED CTLR; 'WHERE'S THE AIRBUS?' CTLR STATED 'HE'S BEHIND YOU NOW; HE HAD TO STOP ON THE RWY WHILE YOU WENT THROUGH TXWY Y12; WITH AN ACFT ON SHORT FINAL TO THE RWY.' CTLR STATED NOTHING ABOUT A GAR OR ANY OTHER TYPE OF CONFLICT; MERELY ADDING THAT THE AIRBUS HAD COME FROM THE HANGAR TO CROSS THE RWY. THE ORIGINAL TAXI INSTRUCTIONS; WHILE READ BACK BY ME VERBATIM; WERE SOMEWHAT UNCLR; AS WE WEREN'T SURE IF WE WERE SUPPOSED TO PROCEED AFTER THE AIRBUS PASSED; OR WAIT FURTHER CLRNC. ALSO UNCLR AS TO WHERE TO LOOK FOR THE AIRBUS (90 DEGS; HARD TO THE L OF OUR POS). WHILE ACFT DO CROSS THE RWY IN THIS FASHION; IT IS NOT THE NORMAL AREA FOR XING; AND SHOULD BE EMPHASIZED WHEN IT DOES OCCUR.