Narrative:

We are using the program tma to meter detroit arrival aircraft in which we are required to follow a number that continuously changes depending on the winds; aircraft restrictions; and who is working with the tma program that day. Time base metering is highly distracting and incredibly difficult to keep up with. I had to vector numerous aircraft for upwards of 10-15 minutes to try to meet times that are false. There were numerous vectors and speed changes to result in the number which is considered acceptable to give to the next center and then the numbers change again without warning. I had an assistant and felt very stressed to devote so much concentration on only four aircraft. There has been little training on how to anticipate the numbers and many cadres admit there is no clear answer to achieve desired results. There was no reason this should have been this busy and complicated since there was no weather; not many aircraft; and there weren't any emergency issues. I would recommend termination of this program. It does not work. It will not ever work in an environment that is always changing. It is dangerous to controllers and pilots since it increases workload on both. It is wasteful of fuel and money. You can not override the program for weather; broken aircraft; pilot needs; and safety. If you need to turn an aircraft for traffic you can not meet the numbers. If the aircraft is behind the time all of the numbers are wrong because you can not make up that time and the slots are wrong. The sector eventually had to be split off because of all the complexity and headache it caused resulting in shorter bodies on the shift. This whole situation created undue stress.

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Original NASA ASRS Text

Title: ZAU Controller voiced concern regarding the TMA program used to meter Detroit arrival aircraft; claiming the procedure is complicated; adds workload and user costs; contending the TMA is dangerous.

Narrative: We are using the program TMA to meter Detroit arrival aircraft in which we are required to follow a number that continuously changes depending on the winds; aircraft restrictions; and who is working with the TMA program that day. Time base metering is highly distracting and incredibly difficult to keep up with. I had to vector numerous aircraft for upwards of 10-15 minutes to try to meet times that are false. There were numerous vectors and speed changes to result in the number which is considered acceptable to give to the next Center and then the numbers change again without warning. I had an assistant and felt very stressed to devote so much concentration on only four aircraft. There has been little training on how to anticipate the numbers and many cadres admit there is no clear answer to achieve desired results. There was no reason this should have been this busy and complicated since there was no weather; not many aircraft; and there weren't any emergency issues. I would recommend termination of this program. It does not work. It will not ever work in an environment that is always changing. It is dangerous to controllers and pilots since it increases workload on both. It is wasteful of fuel and money. You can not override the program for weather; broken aircraft; pilot needs; and safety. If you need to turn an aircraft for traffic you can not meet the numbers. If the aircraft is behind the time all of the numbers are wrong because you can not make up that time and the slots are wrong. The sector eventually had to be split off because of all the complexity and headache it caused resulting in shorter bodies on the shift. This whole situation created undue stress.

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.