DC9 crew confused by taxi instructions issued by tower controller at hou.

Attributes
ACN	415840
Time
Date	199810
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : hou
State Reference	TX
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	DC-9 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	ground other : taxi
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 130 flight time total : 15000 flight time type : 15000
ASRS Report	415840
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other

Narrative:

Taxiing out to runway 12R at hou, we were told to hold short runway 12L. We taxied up to runway 12L and held and contacted tower. Tower then told us to taxi to runway 12R. We crossed runway 12L, and were just over runway 17 when tower cleared us for immediate takeoff. I wasn't sure by the tone of his voice if we had crossed the hold line, or if he just wanted us to go. So we rounded the corner at taxiway east (2 lefts) and departed. Tower didn't say anything but just switched us to departure. The most confusing part to me was that tower just told us to taxi to runway 12R. Not 'up to and hold short' like we normally hear. We were already holding short of runway 12L and it is just a short distance to runway 12R. So, 'up to and hold short' would have been clrer in my mind.

Original NASA ASRS Text

Title: DC9 CREW CONFUSED BY TAXI INSTRUCTIONS ISSUED BY TWR CTLR AT HOU.

Narrative: TAXIING OUT TO RWY 12R AT HOU, WE WERE TOLD TO HOLD SHORT RWY 12L. WE TAXIED UP TO RWY 12L AND HELD AND CONTACTED TWR. TWR THEN TOLD US TO TAXI TO RWY 12R. WE CROSSED RWY 12L, AND WERE JUST OVER RWY 17 WHEN TWR CLRED US FOR IMMEDIATE TKOF. I WASN'T SURE BY THE TONE OF HIS VOICE IF WE HAD CROSSED THE HOLD LINE, OR IF HE JUST WANTED US TO GO. SO WE ROUNDED THE CORNER AT TXWY E (2 LEFTS) AND DEPARTED. TWR DIDN'T SAY ANYTHING BUT JUST SWITCHED US TO DEP. THE MOST CONFUSING PART TO ME WAS THAT TWR JUST TOLD US TO TAXI TO RWY 12R. NOT 'UP TO AND HOLD SHORT' LIKE WE NORMALLY HEAR. WE WERE ALREADY HOLDING SHORT OF RWY 12L AND IT IS JUST A SHORT DISTANCE TO RWY 12R. SO, 'UP TO AND HOLD SHORT' WOULD HAVE BEEN CLRER IN MY MIND.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.