Narrative:

Aircraft Y departed anc en route to ena. Assigned altitude was to be 2000' but anc approach asked for revised altitude of 3000' for traffic (atx Z at 20). I approved the altitude west/O knowledge of atx X departing ena for anc at 3000. To expedite the traffic into ena (Y and Z southbound), I turned commuter Y to the right for spacing. At approximately the same time, I radar identified the northbound atx X over the ena VOR. It was at this point I should have seen the headon situation of aircraft X and Y at 3000. The two aircraft proceeded toward their respective destinations. When the two aircraft were at 4 mi, I noticed the imminent situation. I turned the northbound atx X left heading 270 immediately and also turned aircraft Y left, heading 090 immediately. The aircraft passed with 2.06 NM between them. When the applicable sep was reestablished, atx X proceeded direct anc and aircraft Y to ena. At the time, I was advised that anc center had lost an earth station somewhere in the western half of the state and was requested to relay communication changes and clearance information to other aircraft through a mlt on my frequency. (Radar and communications were apparently out for the entire western half of alaskan airspace.) had I required aircraft Y to climb to 4000 en route to ena, the situation would have been avoided.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN ATX AND COMMUTER ACFT. OPERATIONAL ERROR.

Narrative: ACFT Y DEPARTED ANC ENRTE TO ENA. ASSIGNED ALT WAS TO BE 2000' BUT ANC APCH ASKED FOR REVISED ALT OF 3000' FOR TFC (ATX Z AT 20). I APPROVED THE ALT W/O KNOWLEDGE OF ATX X DEPARTING ENA FOR ANC AT 3000. TO EXPEDITE THE TFC INTO ENA (Y AND Z SBND), I TURNED COMMUTER Y TO THE RIGHT FOR SPACING. AT APPROX THE SAME TIME, I RADAR IDENTIFIED THE NBOUND ATX X OVER THE ENA VOR. IT WAS AT THIS POINT I SHOULD HAVE SEEN THE HEADON SITUATION OF ACFT X AND Y AT 3000. THE TWO ACFT PROCEEDED TOWARD THEIR RESPECTIVE DESTINATIONS. WHEN THE TWO ACFT WERE AT 4 MI, I NOTICED THE IMMINENT SITUATION. I TURNED THE NBOUND ATX X LEFT HDG 270 IMMEDIATELY AND ALSO TURNED ACFT Y LEFT, HDG 090 IMMEDIATELY. THE ACFT PASSED WITH 2.06 NM BTWN THEM. WHEN THE APPLICABLE SEP WAS REESTABLISHED, ATX X PROCEEDED DIRECT ANC AND ACFT Y TO ENA. AT THE TIME, I WAS ADVISED THAT ANC CENTER HAD LOST AN EARTH STATION SOMEWHERE IN THE WESTERN HALF OF THE STATE AND WAS REQUESTED TO RELAY COM CHANGES AND CLRNC INFO TO OTHER ACFT THROUGH A MLT ON MY FREQ. (RADAR AND COMS WERE APPARENTLY OUT FOR THE ENTIRE WESTERN HALF OF ALASKAN AIRSPACE.) HAD I REQUIRED ACFT Y TO CLB TO 4000 ENRTE TO ENA, THE SITUATION WOULD HAVE BEEN AVOIDED.

Data retrieved from NASA's ASRS site as of August 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.