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ZOA controller issues climb clearance to B747 without sufficient spacing from another opposite direction B747 at a higher altitude.
| Attributes | |
| ACN | 543236 |
| Time | |
| Date | 200204 |
| Day | Tue |
| Local Time Of Day | 1801 To 2400 |
| Place | |
| Locale Reference | navaid : bsr.vortac |
| State Reference | CA |
| Altitude | msl single value : 31000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zoa.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | B747-400 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | cruise : level |
| Flight Plan | IFR |
| Aircraft 2 | |
| Controlling Facilities | artcc : zoa.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | B737-400 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | climbout : intermediate altitude |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | government : faa |
| Function | controller : radar |
| Experience | controller non radar : 12 controller radar : 13 controller supervisory : 6.5 controller time certified in position1 : 6 flight time total : 85 |
| ASRS Report | 543236 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Events | |
| Anomaly | non adherence : published procedure non adherence : required legal separation |
| Independent Detector | atc equipment : conflict alert |
| Resolutory Action | none taken : insufficient time |
| Consequence | faa : investigated |
| Miss Distance | horizontal : 26250 vertical : 200 |
| Supplementary | |
| Problem Areas | Flight Crew Human Performance ATC Human Performance |
| Primary Problem | ATC Human Performance |
| Air Traffic Incident | Operational Error |
Narrative:
Aircraft #1 nwbound from lax to ZZZ, first officer, via rzs libbo, briny, alcoa, FL310. Aircraft #2 sebound on the offshore route, FL290. Aircraft #2 requested FL330 and was cleared to maintain FL330. At time of clearance, aircraft were 20 NM nose-to-nose. When conflict alert activated, I issued aircraft #2 a 30 degree left turn which was read back, I then issued aircraft #1 a 30 degree left turn, with no acknowledgment. 7 seconds later, I issued aircraft #1 a 50 degree left turn, which was read back. I then turned aircraft #2 an additional 20 degrees left. Vectors were not timely enough to prevent the loss of separation.
Original NASA ASRS Text
Title: ZOA CTLR ISSUES CLB CLRNC TO B747 WITHOUT SUFFICIENT SPACING FROM ANOTHER OPPOSITE DIRECTION B747 AT A HIGHER ALT.
Narrative: ACFT #1 NWBOUND FROM LAX TO ZZZ, FO, VIA RZS LIBBO, BRINY, ALCOA, FL310. ACFT #2 SEBOUND ON THE OFFSHORE RTE, FL290. ACFT #2 REQUESTED FL330 AND WAS CLRED TO MAINTAIN FL330. AT TIME OF CLRNC, ACFT WERE 20 NM NOSE-TO-NOSE. WHEN CONFLICT ALERT ACTIVATED, I ISSUED ACFT #2 A 30 DEG L TURN WHICH WAS READ BACK, I THEN ISSUED ACFT #1 A 30 DEG L TURN, WITH NO ACKNOWLEDGMENT. 7 SECONDS LATER, I ISSUED ACFT #1 A 50 DEG L TURN, WHICH WAS READ BACK. I THEN TURNED ACFT #2 AN ADDITIONAL 20 DEGS L. VECTORS WERE NOT TIMELY ENOUGH TO PREVENT THE LOSS OF SEPARATION.
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.