Narrative:

I had been working the radar position at sector xx for about 45 minutes when a CRJ2 checked in at FL320. A PA46T was in my sector; having departed and leveling at FL210. The CRJ2 was still in sector yy's airspace when they requested lower. I called sector yy and requested control; which was granted. I issued a descent clearance to the CRJ2 to FL220. The pilot read back FL220. The routes of both aircraft were coincident and opposite direction. As the CRJ2 was leaving about FL240; I issued traffic advisories to the PA46T; stating that his traffic was at '12 o'clock; 8 miles; northwest bound; a crj descending to FL220.' the PA46T replied that he was looking for the traffic. I then issued traffic to the CRJ2 as they were leaving about FL230; 'traffic at your 12 o'clock; 7 miles southeast bound at FL210. Clear of that traffic; I'll have lower.' the CRJ2 replied 'roger; leveling. Have the traffic on TCAS; looking.' less than 15 seconds later; a couple of garbled and broken transmissions were made followed by; 'we got a RA [resolution advisory]...you got any traffic in our area for the CRJ2?' I look back at the area they are in; and noticed the radar targets were less than 3 miles and 800 ft separation. I replied; 'yeah. Maintain 220. That traffic is the traffic I just called to you. Break. Acft Y descend and maintain FL200.' about this time; the radar targets were less than a mile and 200 ft separation; passing abreast each other. The PA46T replied; 'roger descending to 200. That traffic just passed off our left wing. Still want us to descend?' I replied; 'well; if that traffic is past you; you can maintain FL210.' in the mean time; the CRJ2 had begun to climb back to FL220 and had reached FL220 by the time they had exited the j-ball [5 mile ring] around the PA46T. Then the CRJ2 transmitted; 'that traffic is no factor for us.' I concurred via radar data and continued their descent to 110. The whole incident occurred in perhaps only 30 seconds; the closest I observed them coming to each other was less than a mile and less than 100 ft. No longer use 1;000 ft separation minima. Increase to 2;000 ft regardless of altitude stratum/aircraft type/navigation equipment. It is a lousy recommendation as it negates the use of rvsm airspace for its intended purpose; but if it provides a larger buffer to help prevent any descent/climb deviations; then perhaps it needs to be done.

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Original NASA ASRS Text

Title: Enroute Controller described a TCAS RA event involving climbing traffic and higher level traffic one thousand feet above; the reporter suggesting increased altitude separation be used to prevent same type events.

Narrative: I had been working the RADAR position at Sector XX for about 45 minutes when a CRJ2 checked in at FL320. A PA46T was in my sector; having departed and leveling at FL210. The CRJ2 was still in Sector YY's airspace when they requested lower. I called Sector YY and requested control; which was granted. I issued a descent clearance to the CRJ2 to FL220. The pilot read back FL220. The routes of both aircraft were coincident and opposite direction. As the CRJ2 was leaving about FL240; I issued traffic advisories to the PA46T; stating that his traffic was at '12 o'clock; 8 miles; northwest bound; a CRJ descending to FL220.' The PA46T replied that he was looking for the traffic. I then issued traffic to the CRJ2 as they were leaving about FL230; 'Traffic at your 12 o'clock; 7 miles southeast bound at FL210. Clear of that traffic; I'll have lower.' The CRJ2 replied 'Roger; leveling. Have the traffic on TCAS; looking.' Less than 15 seconds later; a couple of garbled and broken transmissions were made followed by; 'We got a RA [resolution advisory]...you got any traffic in our area for the CRJ2?' I look back at the area they are in; and noticed the RADAR targets were less than 3 miles and 800 FT separation. I replied; 'Yeah. Maintain 220. That traffic is the traffic I just called to you. Break. Acft Y descend and maintain FL200.' About this time; the RADAR targets were less than a mile and 200 FT separation; passing abreast each other. The PA46T replied; 'Roger descending to 200. That traffic just passed off our left wing. Still want us to descend?' I replied; 'Well; if that traffic is past you; you can maintain FL210.' In the mean time; the CRJ2 had begun to climb back to FL220 and had reached FL220 by the time they had exited the J-ball [5 mile ring] around the PA46T. Then the CRJ2 transmitted; 'That traffic is no factor for us.' I concurred via RADAR data and continued their descent to 110. The whole incident occurred in perhaps only 30 seconds; the closest I observed them coming to each other was less than a mile and less than 100 FT. No longer use 1;000 FT separation minima. Increase to 2;000 FT regardless of altitude stratum/aircraft type/navigation equipment. It is a lousy recommendation as it negates the use of RVSM airspace for its intended purpose; but if it provides a larger buffer to help prevent any descent/climb deviations; then perhaps it needs to be done.

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.