Narrative:

Situation involved departure air carrier X filed elp J86 fst iah FL250 and inbound cpr Y to elp descending. Due to traffic cpr Y was cleared from over SFL-elp which placed the inbound in the departure corridor. Then an air carrier flight departed elp filed J86 and air carrier X flight departed 10 mi in trail. The air carrier flight intercepted J86 and proceeded on course and was no factor to inbound cpy Y. Air carrier X failed to join the airway and continued on an easterly heading. When approximately 5 mi east of the airway air carrier X was cleared to fly heading 100 for traffic. Cpr Y was assigned heading 275. Approximately 1 1/2 mins later realizing the headings would result in less than 5 mi, air carrier X was reclred to maintain FL210, then cpr Y was reclred to maintain FL220. Cpr Y said 'roger we're out of FL220 can we go on down to FL200?' controller responded 'roger, maintain FL200 for now!' however, I thought I said maintain FL220. Cpr Y acknowledged with a 'roger'. When cpr Y was noted out FL217 I thought he had missed the altitude and was climbing back to FL220. The next hit indicated FL214. I then stated 'cpr Y maintain FL220, FL220.' cpr Y reported leaving FL210 for 220. I then cleared air carrier X to maintain FL200. Air carrier X replied 'we're out of that already and descending back.' aircraft were seen FL207 and FL203 with 4.7 mi.

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Original NASA ASRS Text

Title: ACR X FAILED TO COMPLY WITH ATC CLRNC. PLT DEVIATION. ACR X HAD LESS THAN STANDARD SEPARATION FROM CPR Y. SYSTEM ERROR.

Narrative: SITUATION INVOLVED DEP ACR X FILED ELP J86 FST IAH FL250 AND INBND CPR Y TO ELP DESCENDING. DUE TO TFC CPR Y WAS CLRED FROM OVER SFL-ELP WHICH PLACED THE INBND IN THE DEP CORRIDOR. THEN AN ACR FLT DEPARTED ELP FILED J86 AND ACR X FLT DEPARTED 10 MI IN TRAIL. THE ACR FLT INTERCEPTED J86 AND PROCEEDED ON COURSE AND WAS NO FACTOR TO INBND CPY Y. ACR X FAILED TO JOIN THE AIRWAY AND CONTINUED ON AN EASTERLY HDG. WHEN APPROX 5 MI E OF THE AIRWAY ACR X WAS CLRED TO FLY HDG 100 FOR TFC. CPR Y WAS ASSIGNED HDG 275. APPROX 1 1/2 MINS LATER REALIZING THE HDGS WOULD RESULT IN LESS THAN 5 MI, ACR X WAS RECLRED TO MAINTAIN FL210, THEN CPR Y WAS RECLRED TO MAINTAIN FL220. CPR Y SAID 'ROGER WE'RE OUT OF FL220 CAN WE GO ON DOWN TO FL200?' CTLR RESPONDED 'ROGER, MAINTAIN FL200 FOR NOW!' HOWEVER, I THOUGHT I SAID MAINTAIN FL220. CPR Y ACKNOWLEDGED WITH A 'ROGER'. WHEN CPR Y WAS NOTED OUT FL217 I THOUGHT HE HAD MISSED THE ALT AND WAS CLIMBING BACK TO FL220. THE NEXT HIT INDICATED FL214. I THEN STATED 'CPR Y MAINTAIN FL220, FL220.' CPR Y REPORTED LEAVING FL210 FOR 220. I THEN CLRED ACR X TO MAINTAIN FL200. ACR X REPLIED 'WE'RE OUT OF THAT ALREADY AND DESCENDING BACK.' ACFT WERE SEEN FL207 AND FL203 WITH 4.7 MI.

Data retrieved from NASA's ASRS site as of July 2007 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.