 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
ZID controller vectors and descends sbound traffic to clear eastbound traffic but turns descending, vectored traffic too tight behind eastbound traffic and loses lateral separation requirement.
| Attributes | |
| ACN | 443423 |
| Time | |
| Date | 199907 |
| Day | Sat |
| Local Time Of Day | 0601 To 1200 |
| Place | |
| Locale Reference | navaid : bkw.vortac |
| State Reference | WV |
| Altitude | msl single value : 33000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zid.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | MD-80 Series (DC-9-80) Undifferentiated or Other Model |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | other vortac |
| Flight Phase | cruise : level |
| Route In Use | enroute airway : j42.airway |
| Flight Plan | IFR |
| Aircraft 2 | |
| Controlling Facilities | artcc : zid.artcc |
| Operator | common carrier : air carrier |
| Make Model Name | MD-80 Series (DC-9-80) Undifferentiated or Other Model |
| Operating Under FAR Part | Part 121 |
| Navigation In Use | other vortac |
| Flight Phase | cruise : enroute altitude change |
| Route In Use | enroute : on vectors enroute : direct |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | government : faa |
| Function | controller : radar controller : handoff position |
| Qualification | controller : developmental |
| Experience | controller limited radar : 9 |
| ASRS Report | 443423 |
| Person 2 | |
| Affiliation | government : faa |
| Function | controller : radar |
| Qualification | controller : developmental controller : radar |
| Experience | controller radar : 10 controller time certified in position1 : 9 |
| ASRS Report | 443772 |
| Events | |
| Anomaly | conflict : airborne less severe non adherence : published procedure non adherence : required legal separation |
| Independent Detector | atc equipment : conflict alert other controllera other controllerb |
| Resolutory Action | controller : issued new clearance |
| Consequence | faa : investigated |
| Miss Distance | horizontal : 25800 vertical : 900 |
| Supplementary | |
| Problem Areas | ATC Human Performance Airspace Structure |
| Primary Problem | ATC Human Performance |
| Air Traffic Incident | Operational Error |
Narrative:
X eastbound at FL330 J42. Y ssw FL350 and descending to FL290. Aircraft Y turned right behind aircraft X. When aircraft Y appeared to have lateral separation behind aircraft X, radar controller turned aircraft Y back direct hmv. After the turn, aircraft Y then lost lateral separation with aircraft X on the backside. Supplemental information from acn 443772: Y at FL350 was 10 mi east of hvq inbound to clt. By letter of agreement the aircraft must be level FL290 at the ZTL boundary. X was on J42 west of bkw eastbound at FL330. I had vectored (Y) to accommodate his descent to FL290 and to avoid conflicting with X when I cleared Y to resume navigation direct hmv (arrival transition VORTAC for the clt flts). His abrupt turn caused the conflict alert to activate and I then issued turns to both aircraft to avoid the conflict. However, separation was lost.
Original NASA ASRS Text
Title: ZID CTLR VECTORS AND DSNDS SBOUND TFC TO CLR EBOUND TFC BUT TURNS DSNDING, VECTORED TFC TOO TIGHT BEHIND EBOUND TFC AND LOSES LATERAL SEPARATION REQUIREMENT.
Narrative: X EBOUND AT FL330 J42. Y SSW FL350 AND DSNDING TO FL290. ACFT Y TURNED R BEHIND ACFT X. WHEN ACFT Y APPEARED TO HAVE LATERAL SEPARATION BEHIND ACFT X, RADAR CTLR TURNED ACFT Y BACK DIRECT HMV. AFTER THE TURN, ACFT Y THEN LOST LATERAL SEPARATION WITH ACFT X ON THE BACKSIDE. SUPPLEMENTAL INFO FROM ACN 443772: Y AT FL350 WAS 10 MI E OF HVQ INBOUND TO CLT. BY LETTER OF AGREEMENT THE ACFT MUST BE LEVEL FL290 AT THE ZTL BOUNDARY. X WAS ON J42 W OF BKW EBOUND AT FL330. I HAD VECTORED (Y) TO ACCOMMODATE HIS DSCNT TO FL290 AND TO AVOID CONFLICTING WITH X WHEN I CLRED Y TO RESUME NAV DIRECT HMV (ARR TRANSITION VORTAC FOR THE CLT FLTS). HIS ABRUPT TURN CAUSED THE CONFLICT ALERT TO ACTIVATE AND I THEN ISSUED TURNS TO BOTH ACFT TO AVOID THE CONFLICT. HOWEVER, SEPARATION WAS LOST.
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.