Air carrier taxiing for departure at dtw described near conflict and clearance confusion event resul...

Narrative:

Pushed back from the gate during a high traffic congestion time for ground control at dtw. We notified ATC ground of our location as specified by the ramp controller. We were instructed to follow the B-757 from our right onto uniform; and hold short of kilo for runway 4R. We accepted and begun the taxi. During taxi on uniform; ground control asked us to follow an md-80 from our right to yankee. The md-80 was southbound on yankee holding short of kilo 10. I read back 'behind the md-80 onto yankee; md-80 in sight. The captain and I both acknowledged that the ground controller sounded stressed and behind the curve; due to the numerous aircraft during this time. We heard no further advisements from ATC and continued south onto yankee behind the md-80 as instructed. We had just turned onto yankee at kilo 10 and were approaching yankee 9; when the captain asked me if ATC asked us to hold at yankee 9. There was a crj holding on yankee 9 short of yankee. I told him we were not instructed to hold short of yankee 9; but assigned to follow the md-80 onto yankee which we had done. Just as I responded to him; ATC urgently said 'air carrier X stop!' I repeated over ATC ' air carrier X stopping.' ATC told us to switch frequencies. I did so and heard ATC ground controller ask if we were on frequency. I responded that we were; and we were told to stop; we followed instructions; let the crj in from yankee 9 and no further incident arose. I believe the ATC ground handler was overloaded and did not recognize his compromised situation during this high work load time. I feel that there was too many aircraft at the present time; and an ATC error was made and unnoticed by the flight crew. This error was either to ask us to switch frequencies once on yankee; or to stay on the first frequency and hold short of yankee 9 on yankee. Due to the occasions that ground controllers frequently control numerous sectors; we were not alarmed when a request to switch frequencies was not given by ATC. And since the crj was on the other frequency; we could not hear the transmissions from ATC to the crj. We were unaware that the crj may have been requested to cut in front of our aircraft at yankee 9.

Original NASA ASRS Text

Title: Air carrier taxiing for departure at DTW described near conflict and clearance confusion event resulting in required immediate stop on the taxiway; reporter indicating traffic volume and controller mix up as causal factors.

Narrative: Pushed back from the gate during a high traffic congestion time for Ground Control at DTW. We notified ATC Ground of our location as specified by the Ramp Controller. We were instructed to follow the B-757 from our right onto Uniform; and hold short of Kilo for Runway 4R. We accepted and begun the taxi. During taxi on Uniform; Ground Control asked us to follow an MD-80 from our right to Yankee. The MD-80 was southbound on Yankee holding short of Kilo 10. I read back 'behind the MD-80 onto Yankee; MD-80 in sight. The Captain and I both acknowledged that the ground controller sounded stressed and behind the curve; due to the numerous aircraft during this time. We heard no further advisements from ATC and continued south onto Yankee behind the MD-80 as instructed. We had just turned onto Yankee at Kilo 10 and were approaching Yankee 9; when the Captain asked me if ATC asked us to hold at Yankee 9. There was a CRJ holding on Yankee 9 short of Yankee. I told him we were not instructed to hold short of Yankee 9; but assigned to follow the MD-80 onto Yankee which we had done. Just as I responded to him; ATC urgently said 'Air Carrier X STOP!' I repeated over ATC ' Air Carrier X Stopping.' ATC told us to switch frequencies. I did so and heard ATC Ground Controller ask if we were on frequency. I responded that we were; and we were told to stop; we followed instructions; let the CRJ in from Yankee 9 and no further incident arose. I believe the ATC Ground Handler was overloaded and did not recognize his compromised situation during this high work load time. I feel that there was too many aircraft at the present time; and an ATC error was made and unnoticed by the flight crew. This error was either to ask us to switch frequencies once on Yankee; or to stay on the first frequency and hold short of Yankee 9 on Yankee. Due to the occasions that Ground Controllers frequently control numerous sectors; we were not alarmed when a request to switch frequencies was not given by ATC. And since the CRJ was on the other frequency; we could not hear the transmissions from ATC to the CRJ. We were unaware that the CRJ may have been requested to cut in front of our aircraft at Yankee 9.

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	853706
Time
Date	200909
Local Time Of Day	0601-1200
Place
Locale Reference	DTW.Airport
State Reference	MI
Environment
Flight Conditions	IMC
Aircraft 1
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	Taxi
Flight Plan	IFR
Aircraft 2
Make Model Name	Regional Jet CL65 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Taxi
Flight Plan	IFR
Person 1
Function	First Officer
Qualification	Flight Crew Commercial
Experience	Flight Crew Last 90 Days 35 Flight Crew Total 2300 Flight Crew Type 800
Events
Anomaly	Conflict Ground Conflict Less Severe Deviation - Procedural Clearance Ground Incursion Taxiway

Air carrier taxiing for departure at dtw described near conflict and clearance confusion event resulting in required immediate stop on the taxiway; reporter indicating traffic volume and controller mix up as causal factors.