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ZTL controller described conflict when IFR aircraft was late in responding to vector heading instructions because of TCAS information.
| Attributes | |
| ACN | 702252 |
| Time | |
| Date | 200606 |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | atc facility : ztl.artcc |
| State Reference | GA |
| Altitude | msl single value : 5000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : ztl.artcc |
| Operator | general aviation : personal |
| Make Model Name | Bonanza 36 |
| Operating Under FAR Part | Part 91 |
| Flight Phase | cruise : level |
| Flight Plan | IFR |
| Aircraft 2 | |
| Controlling Facilities | artcc : ztl.artcc |
| Make Model Name | Any Unknown or Unlisted Aircraft Manufacturer |
| Flight Phase | descent : vacating altitude |
| Flight Plan | None |
| Person 1 | |
| Affiliation | government : faa |
| Function | controller : radar |
| Qualification | controller : radar |
| Experience | controller radar : 24 controller time certified in position1 : 24 controller time certified in position2 : 6 |
| ASRS Report | 702252 |
| Person 2 | |
| Affiliation | other |
| Function | flight crew : single pilot oversight : pic |
| Events | |
| Anomaly | conflict : airborne critical |
| Independent Detector | atc equipment : conflict alert aircraft equipment : tcas other controllera |
| Resolutory Action | controller : issued new clearance controller : issued alert flight crew : took evasive action |
| Miss Distance | horizontal : 3000 vertical : 200 |
| Supplementary | |
| Problem Areas | Aircraft Flight Crew Human Performance ATC Human Performance |
| Primary Problem | Ambiguous |
Narrative:
I called traffic to the BE36. 10 O'clock position; 10 mi sebound indicating 6500 ft appears to be descending. The pilot acknowledged the transmission and I added 'if you would like a vector around the traffic I will need to know soon.' it was a bad angle and I knew they were going to be really close. The conversational style of the transmission was a mistake and confused the pilot. This caused several more xmissions. When we got that straight it was already late and I issued a turn that was probably 90 degrees left of course. The pilot commented that they had the traffic on TCAS and the turn would point them right at the traffic. I convinced the pilot to take the turn but it was more of a delay that we didn't have time for. Although the outcome was successful it was much closer than desirable. A 90 degree turn to wind up with less than 1 mi separation. As in so many ATC issues; TCAS seemed to be a hindrance rather than helping.
Original NASA ASRS Text
Title: ZTL CTLR DESCRIBED CONFLICT WHEN IFR ACFT WAS LATE IN RESPONDING TO VECTOR HDG INSTRUCTIONS BECAUSE OF TCAS INFO.
Narrative: I CALLED TFC TO THE BE36. 10 O'CLOCK POS; 10 MI SEBOUND INDICATING 6500 FT APPEARS TO BE DSNDING. THE PLT ACKNOWLEDGED THE XMISSION AND I ADDED 'IF YOU WOULD LIKE A VECTOR AROUND THE TFC I WILL NEED TO KNOW SOON.' IT WAS A BAD ANGLE AND I KNEW THEY WERE GOING TO BE REALLY CLOSE. THE CONVERSATIONAL STYLE OF THE XMISSION WAS A MISTAKE AND CONFUSED THE PLT. THIS CAUSED SEVERAL MORE XMISSIONS. WHEN WE GOT THAT STRAIGHT IT WAS ALREADY LATE AND I ISSUED A TURN THAT WAS PROBABLY 90 DEGS L OF COURSE. THE PLT COMMENTED THAT THEY HAD THE TFC ON TCAS AND THE TURN WOULD POINT THEM RIGHT AT THE TFC. I CONVINCED THE PLT TO TAKE THE TURN BUT IT WAS MORE OF A DELAY THAT WE DIDN'T HAVE TIME FOR. ALTHOUGH THE OUTCOME WAS SUCCESSFUL IT WAS MUCH CLOSER THAN DESIRABLE. A 90 DEG TURN TO WIND UP WITH LESS THAN 1 MI SEPARATION. AS IN SO MANY ATC ISSUES; TCAS SEEMED TO BE A HINDRANCE RATHER THAN HELPING.
Data retrieved from NASA's ASRS site as of January 2009 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.