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|
Attributes | |
ACN | 216479 |
Time | |
Date | 199207 |
Day | Fri |
Local Time Of Day | 1801 To 2400 |
Place | |
Locale Reference | atc facility : azq |
State Reference | KY |
Altitude | msl bound lower : 24000 msl bound upper : 24000 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | artcc : zid |
Operator | common carrier : air carrier |
Make Model Name | Medium Large Transport, Low Wing, 2 Turbojet Eng |
Flight Phase | cruise other |
Route In Use | enroute : direct |
Flight Plan | IFR |
Aircraft 2 | |
Operator | common carrier : air carrier |
Make Model Name | Medium Large Transport, Low Wing, 2 Turbojet Eng |
Flight Phase | cruise other |
Route In Use | enroute : direct |
Flight Plan | IFR |
Person 1 | |
Affiliation | government : faa |
Function | oversight : supervisor |
Qualification | controller : radar |
Experience | controller radar : 22 controller supervisory : 6 |
ASRS Report | 216479 |
Person 2 | |
Affiliation | government : faa |
Function | controller : radar |
Qualification | controller : radar |
Experience | controller non radar : 3 |
ASRS Report | 215809 |
Events | |
Anomaly | altitude deviation : excursion from assigned altitude conflict : nmac non adherence : clearance non adherence : required legal separation non adherence : published procedure other anomaly other |
Independent Detector | atc equipment other atc equipment : unspecified aircraft equipment other aircraft equipment : unspecified |
Resolutory Action | controller : issued new clearance flight crew : took evasive action other |
Consequence | faa : investigated |
Miss Distance | horizontal : 0 vertical : 200 |
Supplementary | |
Primary Problem | ATC Human Performance |
Air Traffic Incident | Operational Error Inter Facility Coordination Failure |
Narrative:
Near midair collision occurred due to failure of adjacent sector control team to complete required point out procedure. The control team in my area of specialization failed to recognize that air carrier Y was traffic for air carrier X until the aircraft were in close proximity and the flcs followed the TCASII RA's. In my opinion, this near midair collision was caused by the use of low experience level controllers in high traffic volume. Callback conversation with reporter revealed the following information. The reporter stated the rbl sector radar controller forced a data block on the bkw adjacent sector's radar scope. He then told the rbl manual controller to verbally coordination with the bkw sector. The rbl manual controller said he did not hear the radar controller's request and did not complete the coordination. Conflict alert and error detection had both activated and the radar controller in the bkw sector failed to take action because he didn't know what the rbl radar controller was going to do with air carrier Y. Both air carrier X and Y received TCASII RA's and responded. System error was filed with a subsequent NTSB investigation. Supplemental information from acn 215814. Air carrier Y cleared to and level at FL240 the first officer (flying the aircraft) noted an aircraft at same altitude. It was visually sighted at the same altitude, same bearing, decreasing range at 5 mi from us, bearing 10 O'clock. Captain asked ZID about the traffic. Shortly after TCASII gave a TA followed by a RA to descend. First officer disconnected autoplt descended 250 ft. TCASII gave 'monitor vertical speed.' we leveled at 23750. Center told us to climb to FL250. We informed him we were complying with TCASII RA. Controller subsequently told us to descend to FL230 then to FL220. The TCASII alerted us early so we didn't have to maneuver violently. It most certainly prevented what otherwise would have been a very close call.
Original NASA ASRS Text
Title: ACR X HAD NMAC LTSS FROM ACR Y. ACR X TCASII TA RA CLB. ACR Y TCASII TA RA DSND. ACR X AND Y EVASIVE ACTION TAKEN. SYS ERROR.
Narrative: NMAC OCCURRED DUE TO FAILURE OF ADJACENT SECTOR CTL TEAM TO COMPLETE REQUIRED POINT OUT PROC. THE CTL TEAM IN MY AREA OF SPECIALIZATION FAILED TO RECOGNIZE THAT ACR Y WAS TFC FOR ACR X UNTIL THE ACFT WERE IN CLOSE PROX AND THE FLCS FOLLOWED THE TCASII RA'S. IN MY OPINION, THIS NMAC WAS CAUSED BY THE USE OF LOW EXPERIENCE LEVEL CTLRS IN HIGH TFC VOLUME. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO. THE RPTR STATED THE RBL SECTOR RADAR CTLR FORCED A DATA BLOCK ON THE BKW ADJACENT SECTOR'S RADAR SCOPE. HE THEN TOLD THE RBL MANUAL CTLR TO VERBALLY COORD WITH THE BKW SECTOR. THE RBL MANUAL CTLR SAID HE DID NOT HEAR THE RADAR CTLR'S REQUEST AND DID NOT COMPLETE THE COORD. CONFLICT ALERT AND ERROR DETECTION HAD BOTH ACTIVATED AND THE RADAR CTLR IN THE BKW SECTOR FAILED TO TAKE ACTION BECAUSE HE DIDN'T KNOW WHAT THE RBL RADAR CTLR WAS GOING TO DO WITH ACR Y. BOTH ACR X AND Y RECEIVED TCASII RA'S AND RESPONDED. SYS ERROR WAS FILED WITH A SUBSEQUENT NTSB INVESTIGATION. SUPPLEMENTAL INFO FROM ACN 215814. ACR Y CLRED TO AND LEVEL AT FL240 THE FO (FLYING THE ACFT) NOTED AN ACFT AT SAME ALT. IT WAS VISUALLY SIGHTED AT THE SAME ALT, SAME BEARING, DECREASING RANGE AT 5 MI FROM US, BEARING 10 O'CLOCK. CAPT ASKED ZID ABOUT THE TFC. SHORTLY AFTER TCASII GAVE A TA FOLLOWED BY A RA TO DSND. FO DISCONNECTED AUTOPLT DSNDED 250 FT. TCASII GAVE 'MONITOR VERT SPD.' WE LEVELED AT 23750. CTR TOLD US TO CLB TO FL250. WE INFORMED HIM WE WERE COMPLYING WITH TCASII RA. CTLR SUBSEQUENTLY TOLD US TO DSND TO FL230 THEN TO FL220. THE TCASII ALERTED US EARLY SO WE DIDN'T HAVE TO MANEUVER VIOLENTLY. IT MOST CERTAINLY PREVENTED WHAT OTHERWISE WOULD HAVE BEEN A VERY CLOSE CALL.
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.