Narrative:

An air carrier was assigned 14;000 ft. Beech 65 was VFR conducting parachute jump operations. The jump aircraft had been up and down all day; they had earlier reported that they were going to 13;000 ft. This was in my mind; but I don't remember if they said it specifically this time. The air carrier asked if I had traffic for him; I said 'yes; 12 o'clock 3 miles will stay below you.' the air carrier responded that traffic was not below but level with him. I then asked the beech 65 their altitude; they reported 13;300 ft. Then [I] noticed that the air carrier was 100 ft low; asked if they were descending. The air carrier reported TCAS had them descending and now they were following it to climb. Move parachute jump operations to less congested airspace.

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Original NASA ASRS Text

Title: ZAU Controller was alerted to a TCAS RA experienced by an Air Carrier arrival when the ceiling altitude for a parachute aircraft was miscommunicated.

Narrative: An Air Carrier was assigned 14;000 FT. Beech 65 was VFR conducting parachute jump operations. The jump aircraft had been up and down all day; they had earlier reported that they were going to 13;000 FT. This was in my mind; but I don't remember if they said it specifically this time. The Air Carrier asked if I had traffic for him; I said 'Yes; 12 o'clock 3 miles will stay below you.' The Air Carrier responded that traffic was not below but level with him. I then asked the Beech 65 their altitude; they reported 13;300 FT. Then [I] noticed that the Air Carrier was 100 FT low; asked if they were descending. The Air Carrier reported TCAS had them descending and now they were following it to climb. Move parachute jump operations to less congested airspace.

Data retrieved from NASA's ASRS site as of July 2013 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.