Air carrier landing hou on runway 30L was instructed to exit at M1; hold short of [runway] 30R at de...

Narrative:

After landing at houston hobby; we were rolling out on [runway] 30L when tower asked us to exit at M1 and hold short of [runway] 30R at delta. My first officer read back the instructions and as I was slowing the aircraft down a second tower controller said; 'correction; hold short of 30R on delta.' I understood this to mean exit at delta and passed up M1 for the delta taxiway exit. As all this was happening; one of the controllers issued takeoff clearance to a corporate jet on runway 35. As I was passing M1; tower told us to stop and canceled the corporate jet's takeoff clearance. I stopped the aircraft short of [runway] 35 and looked over my shoulder to find other aircraft. He had barely started to roll so he was stopped also. Tower asked us if we were unable to make M1. I told them that I was confused by the second transmission and asked them what they wanted me to do now. Tower instructed us to exit at delta and hold short 30R. The taxi to the gate was uneventful. The first officer and I talked about the event after shutting down the aircraft at the gate. Both of us agree that the first instruction was crystal clear. The second transmission was unnecessary. We both thought the second transmission wanted us to exit at delta. We were not confused until the tower told us to stop. That's when we realized what was happening. This all happened within a few seconds. My question is; why would tower issue takeoff instructions on a runway [that] crosses our runway before they were sure we were going to make the exit they wanted us on. We were prepared to exit at M1; but the second controller's direction didn't mention M1. After talking to our ATC manager; we both think there was probably training going on in the tower. Houston has varsity controllers that really know how to move metal on and off runways. When they are training; they probably need to slow things down a little.

Original NASA ASRS Text

Title: Air carrier landing HOU on Runway 30L was instructed to exit at M1; hold short of [Runway] 30R at Delta and then issued different instructions from another Controller. Confused; the crew exited at Delta causing an aborted takeoff from Runway 35.

Narrative: After landing at Houston Hobby; we were rolling out on [Runway] 30L when Tower asked us to exit at M1 and hold short of [Runway] 30R at Delta. My First Officer read back the instructions and as I was slowing the aircraft down a second Tower Controller said; 'Correction; hold short of 30R on Delta.' I understood this to mean exit at Delta and passed up M1 for the Delta Taxiway exit. As all this was happening; one of the controllers issued takeoff clearance to a corporate jet on Runway 35. As I was passing M1; Tower told us to stop and canceled the corporate jet's takeoff clearance. I stopped the aircraft short of [Runway] 35 and looked over my shoulder to find other aircraft. He had barely started to roll so he was stopped also. Tower asked us if we were unable to make M1. I told them that I was confused by the second transmission and asked them what they wanted me to do now. Tower instructed us to exit at Delta and hold short 30R. The taxi to the gate was uneventful. The First Officer and I talked about the event after shutting down the aircraft at the gate. Both of us agree that the first instruction was crystal clear. The second transmission was unnecessary. We both thought the second transmission wanted us to exit at Delta. We were not confused until the Tower told us to stop. That's when we realized what was happening. This all happened within a few seconds. My question is; why would Tower issue takeoff instructions on a runway [that] crosses our runway before they were sure we were going to make the exit they wanted us on. We were prepared to exit at M1; but the second Controller's direction didn't mention M1. After talking to our ATC Manager; we both think there was probably training going on in the Tower. Houston has varsity controllers that really know how to move metal on and off runways. When they are training; they probably need to slow things down a little.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	965909
Time
Date	201108
Local Time Of Day	0601-1200
Place
Locale Reference	HOU.Airport
State Reference	TX
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	B737-700
Operating Under FAR Part	Part 121
Flight Phase	Landing
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	Takeoff
Person 1
Function	Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 184 Flight Crew Type 8400
Person 2
Function	First Officer
Events
Anomaly	ATC Issue All Types Conflict Ground Conflict Less Severe Deviation - Procedural Clearance Deviation - Procedural Published Material / Policy

Air carrier landing hou on runway 30L was instructed to exit at M1; hold short of [runway] 30R at delta and then issued different instructions from another controller. Confused; the crew exited at delta causing an aborted takeoff from runway 35.