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Air carrier flight crew leveling at FL280 received TCASII TA, then RA to descend. The crew immediately descended and passing through FL275, the TCASII indicated the traffic passed overhead at FL280.
| Attributes | |
| ACN | 411251 |
| Time | |
| Date | 199808 |
| Day | Fri |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | atc facility : elx |
| State Reference | MI |
| Altitude | msl bound lower : 27500 msl bound upper : 28000 |
| Environment | |
| Flight Conditions | IMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zau |
| Operator | common carrier : air carrier |
| Make Model Name | A320 |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | Other Other |
| Flight Phase | cruise other |
| Flight Plan | IFR |
| Aircraft 2 | |
| Make Model Name | Commercial Fixed Wing |
| Operating Under FAR Part | Part 121 |
| Flight Phase | cruise other |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | company : air carrier |
| Function | flight crew : captain oversight : pic |
| Qualification | pilot : atp |
| Experience | flight time last 90 days : 250 flight time total : 6000 flight time type : 250 |
| ASRS Report | 411251 |
| Person 2 | |
| Affiliation | company : air carrier |
| Function | flight crew : first officer |
| Qualification | pilot : instrument pilot : commercial |
| Events | |
| Anomaly | conflict : airborne less severe non adherence : published procedure non adherence : required legal separation other anomaly other |
| Independent Detector | aircraft equipment other aircraft equipment : unspecified other flight crewa |
| Resolutory Action | controller : issued new clearance flight crew : took evasive action none taken : detected after the fact |
| Consequence | Other |
| Miss Distance | horizontal : 2000 vertical : 500 |
| Supplementary | |
| Primary Problem | ATC Human Performance |
| Air Traffic Incident | Operational Error |
Narrative:
As we were leveling at ATC assigned altitude FL280, we noticed on our TCASII that there was traffic converging from our 2 O'clock position, about 15 NM away, and level at FL280. I asked center if they had the traffic. After a short pause, center told us to turn left. By this time our traffic was within 10 NM and still closing. Center told us to climb. However, our TCASII rapidly announced 'traffic, traffic,' 'descend, descend,' so we descended. I told center we were in a TCASII descent. As we descended to FL270 and while passing FL275, our traffic passed overhead, still level at FL280, and within 1/4 - 1/3 NM according to our TCASII. We never saw our traffic due to high altitude haze. Our maneuver did not alarm passenger or flight attendants due to the first officer's smooth inputs. We leveled at FL270, and after our traffic was clear, center cleared us back on course, cleared us to climb to our cruise altitude, and told us not to worry about our descent. I believe center missed seeing our traffic. I believe without our TCASII I wouldn't be able to write this report.
Original NASA ASRS Text
Title: ACR FLC LEVELING AT FL280 RECEIVED TCASII TA, THEN RA TO DSND. THE CREW IMMEDIATELY DSNDED AND PASSING THROUGH FL275, THE TCASII INDICATED THE TFC PASSED OVERHEAD AT FL280.
Narrative: AS WE WERE LEVELING AT ATC ASSIGNED ALT FL280, WE NOTICED ON OUR TCASII THAT THERE WAS TFC CONVERGING FROM OUR 2 O'CLOCK POS, ABOUT 15 NM AWAY, AND LEVEL AT FL280. I ASKED CTR IF THEY HAD THE TFC. AFTER A SHORT PAUSE, CTR TOLD US TO TURN L. BY THIS TIME OUR TFC WAS WITHIN 10 NM AND STILL CLOSING. CTR TOLD US TO CLB. HOWEVER, OUR TCASII RAPIDLY ANNOUNCED 'TFC, TFC,' 'DSND, DSND,' SO WE DSNDED. I TOLD CTR WE WERE IN A TCASII DSCNT. AS WE DSNDED TO FL270 AND WHILE PASSING FL275, OUR TFC PASSED OVERHEAD, STILL LEVEL AT FL280, AND WITHIN 1/4 - 1/3 NM ACCORDING TO OUR TCASII. WE NEVER SAW OUR TFC DUE TO HIGH ALT HAZE. OUR MANEUVER DID NOT ALARM PAX OR FLT ATTENDANTS DUE TO THE FO'S SMOOTH INPUTS. WE LEVELED AT FL270, AND AFTER OUR TFC WAS CLR, CTR CLRED US BACK ON COURSE, CLRED US TO CLB TO OUR CRUISE ALT, AND TOLD US NOT TO WORRY ABOUT OUR DSCNT. I BELIEVE CTR MISSED SEEING OUR TFC. I BELIEVE WITHOUT OUR TCASII I WOULDN'T BE ABLE TO WRITE THIS RPT.
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.